synchronous electric clock - world radio history

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182 NEWNES PRACTICAL MECHANICS March, 1944

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Owing to the paper shortage "The Cyclist," "Practical Motorist," and "Home Movies "temporarily incorporated.

Editor : F. J. CAMM

VOL. XI. MARCH, 1944 No. 126

are

BY THE EDITOR

Post-war Technical EducationIAM glad to notice that provisions are, to

be made in the new Education Bill fortechnical education, but details are not

given. It was recently stated in Parliamentthat technical education in this country wasfar below that of any other industrial nation.If this is true, the Government accuses itself.Free education in this country was launchedwith a great fanfare of trumpets in 1888,when Gladstone introduced his famousEducation Act, which made it' compulsoryfor parents to send their children to schoolfrom the age of five until the age of 14.

Strange though it may sound, the verypeople who pressed for free education-namely those who would benefit by it-werethe first to oppose it. They wanted freeeducation of the sort where they could gowhen they wanted to-turn up when theyliked. No system of education could pos-sibly succeed on those lines, and so educa-tion was made compulsory, with schoolhours and holiday periods laid down bystatute. It is perhaps one of our nationaldefects that things have to be made compul-sory, because the' voluntary system in any-thing has always failed. People have to bedragooned into doing things for their ownbenefit. However, the system worked well,and the early school curriculum was mainlyconcerned with teaching scholars the rudi-ments of the three R's-reading, writing andarithmetic.

Before that time those who could affordeducation sent their children to a kinder-garten (a nice, snobbish German word, whichenabled the pseudo intelligentsia of theperiod to lead their neighbours to believethat it was an academic establishment), or toa ragged school, or if they wanted to bereally snobbish, to one of the schools wherethe scholars paid is. a week. For the nextten years the school curriculum was gradu-ally improved to include such subjects asmathematics, music, religion, physical train-ing, physiology, health, aild later proceededto the school clinics' where the child's healthwas subject to periodical inspection. Then,of course, came various trade slumps, andChancellors of the Exchequer lopped con-siderable lumps off the Government grantfor education, so that the curriculum hadto be cut.

During this process of reduction, sciencewas leaping ahead in other directions. Radio,the aeroplane, bicycles, the motor car,the pneumatic tyre, and many other .inven-tions were being developed by the pioneers.So whilst our heritage of knowledge wa'sbeing enriched and increased, the reply ofthe Government was to cut down- the train-

ing and the education which would enableone to absorb it.

Other nations had more foresight, and inGermany particularly the Government of theday saw that the key to their national aspira-tion was to create a highly intelligent raceof capable, trained technicians, and it isbeyond all doubt that Germany did achievethis object. This country and others lapsedbehind and bought goods from abroad whichcould not be made here becatise we hadnot trained the people to make them, or todesign and produce the machinery whichcould make them.

The cinema, the dance hall, the theatre,and the inordinate national importanceattached to football, have provided counter -attractions which took away from the indi-vidual the time he would normally spendin studying, until to -day large numbers ofpeople understand only reading, writing, andrhythm! The nation must become scien-tifically minded in view of all the newdevelopments *Inch are bound to take placeafter the war. We must live down the gibethat we are a nation of shopkeepers sellingother peoples' goods.

Technical StudyTN an attempt to provide opportunities for-I- technical studying, monotechnics, poly-technics, and evening classes were com-menced, but 'these have not been largelysuccessful because, after a day's work it isfound that the brain is not particularlyreceptive to instruction. Now the 'proposi-tion is to teach it in the schools, and totrain the scholar in the particular field forwhich he shows a natural aptitude. Wemust confess that at the moment we do notsee how this plan can be carried out. Cer-tainly the normal school curriculum in theacademic branches of education must beabsorbed by the student before he receivesa technical education. This will certainlyoccupy him up to the age of 14, and appar-ently for the next two years after his naturalaptitude has been discovered he will bepassed over to a specialist instructor toreceive elementary training in his chosencareer. Attached to each school, therefore,must be a large number of specialists inparticular branches of technology, andexisting schools have neither the capacity,the accommodation, nor the equipment tohandle such a scheme.

Practically every school will have to berebuilt, or considerably augmented. Addi-tionally, we have not sufficient 'teachers ofthe .right type to handle such a scheme. It

timt' to train teachers, and the salaries

they are offered are not particularly attrac-tive. So that aspect of the new EducationBill cannot reach fruition for a number ofyears.

Evening ClassesTHE Government has reached the con -

elusion that segregated technical educa-tion such as is obtained by voluntary attend-ance at evening classes or technical collegesdoes not quite fill the bill, and we areinclined to agree that it is unreasonable toexpect a man to work eight hours a dayand spend three or four at evening classesand at homework. The move, however, isa sound one, and whatever the snags, theplan must be carried out. What is reallywanted is a Minister of Education, and aMinistry of Education, not a fictitious Boardof Education which never meets. Educationhas always been the Cinderella of the Budget.If we have wanted to save money we havealways cut education. We agree that in somedirections the school curriculum and thebasis of examinations are in need of over-haul and drastic revision. Really capablepeople fail to pass exams. on unimportantsubjects like history and geography, yet aregood at science and mathematics, whilstprecocious nitwits collect the glory and thedegree because they can remember a fewtextbook postulates. When they enterindustry they are nearly always found to belacking in energy, enthusiasm, and practicalknowledge. They cannot apply their bookknowledge. Some of those examinationsneed to be abolished. The absurd examina-tion for Matriculation or General SchoolCertificate, and the almost equally monstrousexamination for B.Sc. degree does not pro-vide the individual with the knowledge or,the dignity such examinations shouldprovide.

Nine -tenths of the academical side of oureducation could be cut away, and the indi-vidual left to learn it after he has beentrained to he a useful citizen. During hisschool years his mind should be crowdedwith useful knowledge, not academic know-ledge.

We are glad to notice that in the post-warperiod greater use is' to be made of filmsfor teaching purposes.

"Dictionary of Metals and Alloys"THE Third Edition of the " Dictionary of

Metals and Alloys has just been pub-lished at tos. 6d., or, by post, at us. Ithas been completely revised, and over 15onew definitions have been added. It isobtainable from George Newnes, Ltd., TowerHotise, Southampton Street, Strand, W.C.2.

I


Build inA

Fig. 1.-The finished clock.

WHEN the amateur model -makerlooks around for new subjects onwhich to exercise his skill, the

building of an apparently intricate piece ofapparatus, such as an electric clock, is-.)assed over on the score of requiring specialtools, such as a lathe, gear -cuttingappliances and other apparatus not usuallypossessed by amateurs. It will be foundpossible, however, to construct a highlysatisfactory electric timepiece with perfecttimekeeping capabilities, literally " on thekitchen table."

Unlike'the spring -driven clock, an electricclock of the synchronous variety does notdepend for its accuracy on escapement ofpendulum action. It is driven by a verysmall electric motor, having a minute con-sumption of power, controlled for speedby the frequency of the A.C. electric mainsto which it is connected.

Now that the grid scheme is in operation,practically every power station in thecountry is synchronised from Greenwich,to deliver power at exactly 5o cycles persecond, and, as the speed of the motor isentirely dependent on the frequency, theclock is, virtually, controlled fromGreenwich.

The motor is not self-starting and has tobe rotated by hand until it is running at thespeed at which it is designed to run.

The RotorIn the timepiece, as illustrated, the

rotating pat t of the motor, generally calledthe " rotor," consists of a toothed iron disc,which rotates in an alternating magneticfield, set up by a winding, between the polesof a specially shaped iron magnet system,hereafter called the " stator." Fig. 6 showsthe shape of the rotor and stator, and givestheir dimensions.

The rotor speed, in revs. per minute, isdetermined from the formula 2 f 6on

where

f is frequency in cycles per second, some-times called periods, and n is the numberof teeth on the rotor. In this instance,the mains frequency was 5o c.p.s. and therotor teeth 16 in number, giving a speedof 375 r.p.m or 22,500 per hour. To

a SynchronousElectric Clock

The Construction of This Clock is Simple, and it is

Built Without the Aid of a Lathe or Special Toolsreduce this speed to I perhour calls for a reduction gear22,50o to 1. This seeminglyhuge reduction is obtained,very simply, in four steps of3 to I, 3 to I, 50 to I, and5o to 1, by employing gearwheels.

It is to be noted that theclock is rather larger than isusual with purchased ones.The overall size, including thecase, is approximately Sin.square by 6in. back to front.These dimensions are occa-sioned by the size of the gearwheels employed. The largesize is not considered a dis-advantage as the more usual34in. dial is rather' small to beread at a distance.

MaterialsCommence construction by gathering

together the material required as detailed inthe list of parts. The gears, sprocketwheels, collars, plated washer, axle rod,perforated plate and grub screws can beobtained ready made. The Swedish ironplates and iron strip are obtainable fromany good blacksmith or metal merchant. IfSwedish iron is not readily obtainable, mildsteel will do quite well. A good radio dealerwill supply the D.S.C. wire, 2 B.A. screwedrods, nuts, washers, 4 B.A. and 6 B.A.screws, ebonite and transformer stamp-ings.

Take the wider of the two iron platesand having polished off any rust and scalewhich may be adhering to it, scribe the lineA -B 1.1-2in. down from the long edge. (SeeFig. 6.) On the line A B mark off hole tand drill with a 5/32in. drill.

Drilling OperationsDrive a pin, cut from the axle rod, into

this hole and use the pin to position theperforated plate which will guide the drillfor drilling hole 2. Secure the platefirmly to hole 2, in a similar manner,and using it as a template, drill out holes4, 5, 6 and 7. With the plate still inposition, use the 5/32in. drill to indentthe centre of hole 3. Do not drill thishole right through at this stage.

Remove the template and using theindent for hole 3 as centre, scribe, withcompasses, a circle of it in. radius. Atthe same time scribe a second circle ofI 17/64in. radius. By bisection, dividethe circumference of the smaller circleinto 16 equal parts, and with a centrepunch, mark each point of intersection.Using a drill of 1 /t6in. diameter, drillpilot holes for the 16 holes on the circum-ference of the circle. Hole .3 may nowbe drilled out 5/32in. diameter. Greatcare must be taken to make these holesexactly in the correct position and deadsquare with the surface of the plate.

Before proceeding to enlarge the holesalready drilled to their finished sizes, thenarrower plate should be cleaned upand, with the aid of the perforated plate,holes to correspond to 1 and 2 drilled.

These holes will permit the narrow plateto be secured to the back of the wide one.The wide plate now becomes a template,and drilling is continued until all holes butone are present in both plates. The .excep-tion is hole 3, which should only be indented,as it is used as a centre for scribing thefinished size of the rotor, i.e., 1 15/64in.radius.

Having drilled out all the pilot holes inboth plates, attention should be turned tothe rear rotor bearing strip, which is of brass41in. x xi / t6in. (approx.).

It essential that this bearing strip andthe gear_ plates be of brass or other non-magnetic metal. If iron were used for themthey would short circuit the field betweenthe stator poles.

The centres for the bearing and supportholes can be marked off from the partlycompleted stator plate. The rear gear platecan be marked off in the same way. -Byadhering to this procedure of marking offall the parts from the stator plate, perfectalignment of the holes is assured.

Holes that are to be a bearing fit for therod are best drilled out with the 5/32in.drill and then " lapped " out with the aidof a small piece of the rod, tapered slightlyto enter the hole, used as a lap in the handdrill. This procedure actually improves thebearings as the lap hardens and polishesthe wearing surface. The holeof the trotor will require a littlefine emery powder and oil as anaid to the " lapping " process.Rotor and Stator Poles

When all the marking off, men-tioned so far, is completed, therotor and stator plates may befinished by opening all the holes


4

Extra th ckness hero

Collars sweatedhere

(f),

/rile wnion here

Mope d.6.54.

4;Fig. 3.-Details of the template for positioning the holes.

out to their final sizes. (See Fig. 6.) Witha hacksaw, cut out the rotor and statorpole pieces as near as possible to theirfinished shape, finishing them down to thedimensions given with files, taking care tokeep the edges square and the concave facesof the pole pieces as true as possible. The

. shaping of the rotor demands especial care.It must be truly round. Any lumps on itscircumference will necessitate increasing thegap between stator and rotor to preventfouling as the rotor revolves. The gapshould not exceed 1/32in.

The rotor is completed by having a lin.diameter, ;in. face pinion sweated to it withthe boss outwards. A short length of axlerod will hold the parts concentric duringthe sweating operation.

Care must be taken to prevent soldercreeping between the teeth of the pinion.

If desired, the iron parts can be givena coat of quick -drying black enamel.

The next step is to fashion the stator polesupports, or legs, from the lin. x lin. ironstrip. It is only necessary for the rearmostpair of strips to be bent to form feet. Thestrips which support the dial form the frontpair of feet.

The Transformer StampingsFrom the transformer stampings cut

sufficient strips, 41in. long by at least in.wide, the exact width is not critical, to equalin thickness the stator pole pieces. Alsocut two pieces of the I by 4 iron 34in. long.The transformer iron strips and the 31in.pieces, together, form the yoke over whichis wound the winding for energising themotor. It is not recommended that thisyoke be made froin solid metal, as its usein magnetic circuits introduces a loss ofenergy which has to be made good byincreased consumption from the mains.

Having completed the iron work for themotor, attention can now be given to finish-ing the rear bearing strip. To provide agreater length of bearing for the rotorspindle, a collar is sweated to it. A shortlength of axle rod will facilitate the sweat-ing process if it is used as suggested forsweating the pinion to the rotor. The col-lars, as purchased, have two tapped holes,but only one grub screw. The extra tappedhole will serve as an oil hole if it ispositioned vertically and oil will not run outof the bearing if the screw is left in place.It must not, of course, be tightened up or itwill grip the rotating spindle.

The draw*, of the rear gear- plate, Fig. 3,gives the position of all the bearing holesfor the gear wheel spindles and their sizes.All the dimensions are not given, as, insome cases, greater accuracy in meshing thevarious wheels can be obtained by followingthe procedure outlined below. The frontgear plate is almost identical with the rearone, and it can be drilled out, with a mini-

mum of labour, by usingthe rear plate as a tem-plate. Immediately abovethe hole for the rotorbearing (a collar is sweatedto this hole when the plateis finished, as with the rearbearing strip), drill hole Awith a 5/32in. drill, lap-ping out the hole to axlesize, as detailed earlier.The exact distance fromthe rotor hole to hole Amay be fixed by employingthe perforated plate as atemplate. On temporaryspindles, mount a in.pinion in the rotor holeand a sijatilar pinion inhole A. Place a IZin. gear

wheel in mesh with both of these pinions,so that its centre takes up a position corre-sponding to hole B, and indent the centre ofhole B. If a strip of thin writing paper,crimped between two pinions, temporarilymounted on the perforated plate for thepurpose of crimping, is inserted between theteeth of the three wheels, prior to nZrkinghole B, sufficient clearance will be automatic-ally allowed for any irregularities in themeshing of the wheel teeth. These samecrimped between two pinions, temporarilyany wheels whose centres are not marked offfrom the perforated metal plate.

Hole B is the bearing for the first reduc-tion gear spindle, which runs at one-thirdrotor speed, and it is advised that it beincreased in length by sweating a small

Fig 4 -Horizontalbearing plates.

Fig. 5.-The six -arm star piece foradjusting the hands.

square of brass over it, and the correspond-ing hole in the front plate, afterwards drillingright through the two thicknesses.

Angle PiecesThe next step is to cut off and clean up

pieces of brass angle strip. Each of

Sra'rorPole

I I

yoke I

Wincltng I

I i

7

9

these is drilled and tapped, using a No. 44drill and 6 B.A. taper tap, to have two holesin each face, symmetrically placed, with in.between centres. These angle pieces areemployed to carry horizontal brass plates,tin. wide by 'in. long, between the frontand rear gear plates. The horizontal platesare drilled with one hole each for a verticalspindle upon which is mounted a 50 -toothwheel and a worm. The position of thespindle holes is indicated in Fig. 4. Asquare is taken out of the corner of eachplate to clear certain gear wheels. Thecutting of these small squares is best leftuntil the assembly is partly completed, whentheir purpose and position will be obvious.Each horizontal plate has, also, four 5/32 in.holes through which 6 B.A. by 4in. round -headed brass screws are inserted to securethe plates to the angle pieces. These holesare deliberately made much larger indiameter, i.e., 5/32in., than is necessary. Byso doing, and employing washers under thescrew heads, the plates are given a fairamount of play which allows for adjustmentof the meshing of a worm on the spindle inhole A and the 50 -tooth wheel on thevertical spindle. The screws are, of course,tightened down after the meshing is satis-factory.

The position of the screw holes on thegear plates to which the brass angle piecesare secured is indicated in Fig. 3. They,also, are drilled 5/32in.

LIST OF PARTSI piece of Swedish iron 41in. x 3lin. x 5/32in. thick.

piece of Swedish iron, 4lin. x Sin. x 5/32in. thick.strip of brass, rain. x 21in. x x/r6in. thick.

r length of angle brass, 6in. x lin. x x sin. thick.t length of iron strip, 3ft. x lin. x tin. thick.

piece of ebonite 4in. x 2in. x 3/i6in. thick.8 ozs. of 36 S.W.G. double -silk -covered copper wire.2 rein. lengths of 2 B.A. screwed brass rod.38 2 B.A. brass lock nuts and washers.4 4 B.A. x lin. cs. brass screws and hex. nuts.18 6 B.A. x fin. round head brass screws and

washers.A few transformer core stampings. (Sec text.)4 19 -tooth pinions, 4in. dia. x face.2 25 -tooth pinions, tin. dia. x lin. face.4 5o -tooth gear wheels, shin. dia.3 57 -tooth gear wheels, I /in. dia.2 worm drives.6 metal collars.24 plated washers.15 5/32in. grub screws.2 r i1in. axle rods.i sprocket wheel, r lin. dia.r sprocket wheel, lies. dia.

perforated flanged plate, si in. x z§ in. (Used as atemplate for drilling the holes.)

Black enamel, celluloid lacquer, cardboard for dial,glass lot case, etc.

. (To be continued.)

Rear Rotor Bearing b._ faStrIp /6

3

2134"od

2 BA .rod

Dial -

4 BA screw

Fig. 6.-Showing the construction of the stator and rotor.


LAST month we described how torewind a Lucas A9ooC dynamo tomake it charge at low speeds for

.wind -charger use. In this article, instruc-tions are given for building a good wind -charger with this particular dynamo.

Turntable and Slip RingThe turntable is built on the lines

suggested in the first article of the series.Two iron pipes (r) and (2), Fig. r, about

and 21 in. diameter and 3ft. long, litclosely together in one another. The cross -arm, which carries the dynamo and tail,. ismade from two flat iron bars (32), Figs. 2

Small Wind-power Plants -3Constructional Details of a Serviceable Unit. By W. H. SUTHERLAND

(Continued from page 154, February issue.)

the block. If necessary, slip -ring andwooden blocks are all secured by counter-sunk wood screws, but they should all fitso that considerable force is necessary todrive them home. A piece of brass actsas a soldering tag for the slip -ring.

The brush ring (15) is taken from a Fordself-starter, and contains four heavy copperbrushes. 'The two insulated ones areremoved, leaving the two diametricallyopposite earthed brushes. It is attached byany convenient method to the copper pipe.In the illustration it is soldered by four smallbrass brackets to a clip, made from sheetbrass, which bolts around the copper pipe.

Alternately, the slip

General view of the windcharger described in the text.

and 3, bent at the local forge, and boltedaround the inside pipe. In the photographicillustrations these bars are 3M. x fin, butsomething lighter would do quite well,although they should be wide enough totake four fin. bolts to secure them to thepipe. The bars lie flat against each otheron the side that holds the dynamo, buta space of ;in. is allowed on the shortside for tightening purposes. The bottomof the outside pipe is closed by a woodenblock (4), 3in. or 4in. long, driven tightlyinto the pipe. A length of copper or brasstube (3) fits tightly in this block and passesup through the turntable to carry the controlrope (35) through the oil reservoir (7). Thisis filled through the opening (8) with heavymotor oil when the whole machine is finallymounted on its pole.

The filler (8) is made by tapping a wander -plug socket into a slanting hole. Theoil is poured through a piece of rubber tubejoining the filler to a funnel laced to theside of the windcharger on a calm day. Thecopper pipe 'also carries the positive connec-tion from the slip -ring (6) to the cable (9).This slip -ring is made of brass. The casefrom an old headphone .earpiece, with thebottom cut off, will generally do for thepurpose. It is driven on to the woodenblock (5), which also serves as a supportto centre the top of the copper pipe. Ifit is available, a short piece of pipe (notshown), which fits closely outside the copperpipe, is hammered into the hole in block (5)to act as a " bearing " for the copper pipe,and to prevent enlargement of the hole in

ring may be attachedto the copper pipe,and the brushesbolted to the twopieces of angle -ironwhich hold the ropepulley - drum. Theymust, in this case, beinsulated from theangle -iron, and con-nected together byrubber covered cable.Two connecting clips(to) and (i i), madefrom lin. wide copperstrip, are bolted inposition before thepipes receive theirfirst coat of enamel.The dynamo is fixedon the turntable bytwo iron rings (2r)(22). Here, again, theassistance of thenearest blacksmith isneeded.

Braking SystemIn building a home-made windcharger,

the braking system presents the greatestproblem in the whole design. Commercialunits follow three systems: (I) an internalexpanding friction brake working on a drumat the front of the dynamo. (II) A dynamomounting which tilts up to a vertical posi-tion. (III) A swinging tail -vane shut off.The first type is very efficient and simple,but does not lend itself to home construc-tion. An internal brake drum on thisdynamo would be awkwardly large, whereasan external brake element usually burns outin the first storm.Besides, the problemof governing wouldnot be helped in anyway by this system.

Type H is verysimple in theory, butdrastically weakens avital point in the con-struction of the unit.A dynamo held to theturntable by a singlebearing will sooner orlater vibrate itself dff.The only hope of sur-vival in a home-madeplant lies in excep-tionally strong con-struction.

The " framework "of this unit will standup to any gale that

our climate can produce-more than can besaid for most of the fancy home-made outfitswith ball -bearing turntables and the dynamomounted with its centre of gravity directlyabove the pole, and the propeller tips conse-quently passing the pole with a clearance ofabout IM.

Type III is really the only brake thatcan be used easily on a home-made plant,and it also solves the question of .governing.The main tail is held by a hinge (12), boltedto the cross -arm. The writer was doubtfulabout the strength of such an arrangement,but it has provedquite efficient. A'good hinge, withat least four"bearings," isneeded.

The tail is heldin position by arubber band (3o),cut from a strongmotor tube, andstretched. betweentwo large cottonspools. A rubberband is easier tomount, and worksmore efficientlythan a steel spring.The arm (29),which carries onecotton spool, alsoacts as a stop tolimit the positionof the tail, whichis variable bychanging the spac-ing nuts (27) (28).

To shut off thewindcharger, t h etail is pulled to oneside by the rope,turning the dynamoand propeller outof the wind. Agreat advantage ofthis type of brakeis that the machine Fig. t. - Sectionmay be shut off to through turntablea n y extent re- and supporting tube.quired, so that- itacts as a " trickle -charger " to maintain thebatteries in a full condition. During wintermonths, it is well to make a habit of half -shutting off the wind -charger last thing at

ut

Enlarged detail of the turntable and fittings.

fa

ill°

6

4

March, 1944 NEWNES PRACTICAL MECHANICS. 187

38

NIA

fi

23

tip't;

rij S.

",,,44rzze," A r

24

39

15142'092' r

- 36

111010

Fig. 4.-Section through the fan casing.

40

41

night in case of sudden storms.The pulley (Ili) is made from an empty

wire spool, mounted on the axle of a bicyclewheel between two pieces of angle iron.These rain. or 'lin:angle irons (13) (x7)are slightly opened and closed in a viceto give the slope necessary for the pulley -drum, and are mounted on opposite sidesof the turntable to bring the drum intoposition above the copper tube. Thisnecessitates cutting away a piece of theupright (13) as shown in Fig. 2. A moreefficient and durable pulley is obtained bymounting a complete bicycle rear hub insteadof the wooden spool. The upright (13) alsocarries the bracket (14) which holds therain cover in position.

The second pulley (26) is bolted to a right-angle bracket (34) held by the bolts whichsecure the hinge. Two pieces of aluminiumare bent around this pulley to form guardsfor keeping the rope in the pulley -groove.The pulley should be at least 12in. from theturntable. Remember that wire cannot beused instead of rope, since it would short-circuit the dynamo.

Action of GovernorThe bracket that holds the second pulley -

wheel also has attached to it a length oflight tin. angle iron or circular tube withthe governing vane on its end. The opera-tion of this governor is extremely simple.When the wind pressure on the side vanebecomes sufficiently great to stretch therubber, the side vane closes up with themain tail, turning the dynamo and propellerto one side. When the wind falls, the rubberpulls the dynamo into the normal positionagain. The main tail is so large that it actsas an " anchor " in space against which theside -tail and the rubber exert opposingforces. The length and area of the sidetail is best found by trial while " runningin " the finished windcharger on a smallexperimental pole erected temporarily in awindy spot. Three feet is a suitable lengthto try, with a vane about nin. square.

There is a very important point to beobserved in the construction of this governor.The line drawings and photographs weremade on an anti -clockwise windcharger, sothat for a clockwise dynamo the side -tailwould have to be on the other side from

that illustrated. The reason for this distinc-tion would take too much space to explainbut will be obvious to many readers. Ifbuilt on the wrong side, the side -tail willrefuse to work. The side -tail needs to bestrengthened by a length of wire stretchedfrom its end to the clamping ring (22). Thevane must also be reinforced by several lightbars bolted along its rear side. The tensionin the rubber band is made adjustable byattaching the second spool to a long boltwhose head has been removed, passing thebolt through a hole in a small bracket, andscrewing the nut to any position required.The main -tail is displaced a few degrees byreducing the spacing nuts (28) to balance thepermanent pressure against the side -tail.

If a side governor is used, the tail vaneshould not be less than loin. square. Neveruse a flat iron bar to hold a windcharger tail.It can vibrate in one direction, and soonbreaks off at the " node " of this vibration.Angle iron, or tubing, is rigid in alldirections. The rain cover (r9) is made fromtin, soldered at the edges, and with a"porch " at one side for the rope. It is

6

this latter purpose alone. A small caketin (23), with a diameter the same as that ofthe front plate of the dynamo, is held inposition by the screws that hold the frontplate. The screw heads will force the tin tothe shape of the countersunk holes. Sixholes (38) are drilled through the tin andfront plate. Two intake " scoops " (4r)Figs. 2 and 4, are shaped and soldered to thebotthm of the cake tin, where they will pickup the least rain. One of these can be seenin the first illustration on page 186.

The plate which holds the propeller to theaxle (36) is spaced as far as possible from thedynamo by the piece of pipe (37) whichpresses against the inside race of the dynamobearing. To the back of this plate is attacheda Lid (24) of a second cake tin slightly largerthan the first tin, so that it overlaps the firstby in. A loop of wire is soldered to act asa rim for the first tin, where it has been cutshort., so that no water will make its waybetween the two tins when the machine isshut off on a rainy day.

Six aluminium fan blades are bolted sym-metrically around the plate by 6 B.A. bolts,

25rvi

r`c

R 34

held by the bandand adds greatlyfinished unit,

11

/8 /5

06(11 !WI

17

4m.

(20) and the bracket (14),to the appearance of the

Cooling FanThose who wish may add a forced draught

cooling fan to the front of this dynamo. Aswell as increasing the permissible chargingcurrent, it completely protects the frontbearing from rain. Even if no fan blades arefitted, it is worth while to add the casing for

30

7-11

,11571410

23 24

1131194

jel

322/ 22

Fig. 2.-Side view of the assembledwind -charger.

countersunk on the front of the plate. Theseblades are bent to an angle of 45 degrees.The top one (39) is bent upwards over thehead of the propeller bolt, which it then

Si holds in position, and the bottom one is bentdownwards, also over the head of the otherpropeller bolt. The air draught emergesthrough the brush inspection holes and thegap (25) Fig. 2. A strong plate, 6in. by 4 -}in.,is used as a washer " between the front ofthe propeller blade and the two nuts thathold it, since large local strains in the timbercause it to split at high speeds. A single

mfd. condenser is connected across thebrushes, to prevent radio interference. Themethod of mounting the turntable on awooden pole is clear from the,photOgraphs.

(To be continued)

2, 22

23 24

Fig. 3.--43lan of wind -charger. (Currentcollecting gear and rain -cover omitted.)

' 188 NEWNES PRACTICAL MECHANICS March, 1944

Aircraft FlyinA ControlsTheir Positioning and Functions

By T. E. G. BOWDEN, Grad.R.Ae.S., M.I.E.T.

T0 allow an aircraft to be controlledduring flight it is necessary to incor-

. flying controls. These aresimilar in their method of functioning inthe Majority of aircraft and only the detaildesign varies. The controls fall into two.4,main categories, i.e., fixed and movable.

There are three directions of stability forwhich the controls have to be effective.Firstly, longitudinal stability ; secondly,lateral stability ; and thirdly, directionalstability. The methods of control aroundthese axes (see Fig. t) now follow.

Longitudinal StabilityDue to the fact that the centre of pressure

(the point at which the resultant lift of anaerofoil is assumed to act) of a wing variesaccording to the angle of incidence, a wingby itself is unstable. By increasing theangle of incidence, i.e., raising the leadingedge, the C.P. moves forward, and conse-quently the incidence angle is still furtherincreased. In the same manner, when theincidence is reduced, so the C.P. movestowards the trailing edge, thus depressingthe leading edge. From the above it will be

ElevatorsFig. 2.-Elevators.

seen that a correcting control is required toovercome this instability.

The usual method adopted is to attach afixed horizontal surface at the rear end of thefuselage, and this control is known as thetailplane. The method of functioning is asfollows. When the aircraft nose is raisedthe airflow passing over the tailplane. datesan upward lifting force, consequently tend-ing to cause the nose to drop to its originalposition. For normal flight the airflow doesnot create any lift, as the centre line ofthe tailplane section is usually approxi-mately in line with the airflow. On certainaircraft the tailplane is designed to give anupward or downward lift at normal flyingpositions. As the airflow, when it hastravelled over the wing, is deflected down-wards, the angle of incidence of the tailplanehas to be adjusted to suit this angle ofdownwash, as it is termed.

In order that the pilot may depress orraise the nose of the aircraft, in addition tobeing longitudinally stable, movable controlsurfaces are required. These forth the rearportion of the tailplant and ale known aselevators. Normally, as iliown in Fig. 2,the elevators form a continuous aerofoilsection, usually of the symmetrical type.When the elevators are depressed the lift-ing force is increased, due to the increase incamber. This causes the tail to rise andconsequently depresses 419 noses When theelevators are raised, the resulting lift actsin a downwards direction, thus depressingthe tail and raising the nose.

If the aircraft does not require any opera-tion of the elevator control for normal flight,it is said to be longitudinally stable, l?ut ifit requires correction by use of the elevator,

it is unstable. If a disturb-ance occurs in a stable air-craft the oscillations willgradually die ' out, or viceversa for an unstable design.

To obtain satisfactorylongitudinal stability thewing section should hive assmall a C.P. movement aspossible, and a high aspectratio tailplane of reasonable size is required.

Lateral StabilityThe stability about the longitudinal axis is

termed lateral stability. This movementabout the axis is termed rolling, i.e., one wingtip rises and the other falls.

The controls fitted to govern this move-ment are known as the ailerons, and theirposition is indicated in Fig. 3. As in thecase of the elevators, they are movable, butwith the difference that when one is raisedthe other is lowered.

The manner in which the ailerons func-tion is as follows. If a roll or bank to portis required for a left-hand turn, the star-board aileron is lowered and the port aileron

Main Plane

AileronFig. 3.-Main plane and aileron.

raised. The lowered aileron increases thelift on the starboard wing, and the raisedaileron decreases the port wing's lift. Thusa bank will result in the required direction.The opposite result will take place if theailerons are moved in the reverse directions.

The angles that the port and starboardailerons move through usually vary, i.e.,the upwards moving control travels througha 'greater angle than the lowered one. Thisdifferential action is to decrease the drag ofthe raised wing and increak that of thelOwered wing. If this were not done thedrag tends to turn the aircraft to the rightinstead of to the left. Approximate angularmovements are 20 deg., and 15 deg. down.

Ailerons are sometimes connected withthe movable slats fitted in the leading edge.In this case, when the aileron is depressed,the slat moves away and forms a slot in theusual manner, thus increasing the control atstalling angles.

Low Hinge Point

Fig. 4.-Derailsof Frise aileron.

ventral

Pitching Axis

Yawing Axis Polling Axis

Fig. 1.-Reference axes.

To combat the increased drag mentionedabove a special type of aileron known` asFrise ailerons have been developed. Asshown in Fig. 4, the hinge point and profileis so arranged that when the aileron israised the nose projects outside the profile,but when it is depressed the contour is notdisturbed. By this movement the drag isincreased on the lowered wing and decreasedon the raised wing, i.e., tending to turn theaircraft in the correct direction.

DihedralTo achieve lateral stability without haVing

to continually operate the ailerons the wingis usually given an upward tilt, as shown inFig. 5. The angle between horizontal andthe wing is knOwn as the dihedral angle.

When a wing drops and the aircraft side-slips, the dihedral angle causes the effectiveangle of incidence of that wing to beincreased and vice versa for the rising wing.Thus the lift is increased on the loweredwing, tending to revert the aircraft to itsoriginal position. The dihedral angle varies,but an approximate figure is 5 degrees.

SweepbackAn additional aid to rolling stability is

to sweep the wings backward so that inplan they form a V-shape. By this meansthe effective aspect ratio of the loweredwing,,in a sideslip is increased, thus increas-ing its efficiency and helping to restore theaircraft to the horizontal position.

Other factors affecting rolling stability arethe side areas of the fuselage, fin, etc. Itis obvious that when a sideslip occurs thefin will tend to right the aircraft as thearea is above the centre of gravity, but. iffloats are fitted the roll is increased.

Directional StabilityAn alternative name for directional

stability is weathercock stability, and thesecond title is more explicit. If. an aircraftyaws, i.e., changes direction about thenormal axis, it is said to possess directionalstability if it returns to its original directionof flight.

Stability is obtained by the fin, i.e., thefixed control surface mounted at the rearof the fuselage at right angles to the tail-plane. When the aircraft is deflected bya gust from its. original direction, the pres-sure of the air on the fin will turn theaircraft's nose to the original direction. Theaction is similar to the tail -planes', and, asin their case, a movable control surface ishinged to the rear of the fixed surface.

The movable portion is known as therudder, and allows the pilot to turn hisaircraft either to port or starboard aboutthe normal axis. To turn to port therudder is moved to the left, which gives alifting force, turning the tail to starboard,giving the required movement. It shouldalso be noted that the rudder acts as a


continuation of the fin when in the neutralposition.

Balanced ControlsTo reduce the operating loads required

to deflect the control surfaces, they arealways balanced. In the case of aircraftflying long distances the operating loadsmust be reduced to a minimum, otherwisethe pilot will be fatigued. The controls aretherefore balanced, either aerodynamicallyor statically.

Fig. 7 (a) illustrates an aerodynamicallybalanced control surface. As will be seen,

Dihedral Angie

the hinge line is so arranged that there isa considerable portion of the control forwardof the hinge. When the control surface isturned, the forward position juts out intothe airflow. Thus the air striking thisportion helps to rotate the control in thedirection required. All the controls, i.e.,rudder, ailerons or elevators, may bebalanced, by this method.- An alternative aerodynamical method is

the Servo system. In this design anauxiliary smaller control -is mounted behindthe main control. It is connected up andhinged so that when the main control moves,say, to the right, the servo tab moves inthe opposite direction, i.e., to the left. Theairflow striking the tab assists the pilot inthe movement of the control.

Static balancing is illustrated in Fig. 6 (b)and entails the addition of weights, eitherinternal or external, so that the centre ofgravity of the control coincides approxi-mately with the hinge line. This reducesthe operating loads by a considerableamount. The weights are usually fitted inthe control leading edge.

The static balancing also assists in theavoidance of flutter, and is commonlycarried out for all high-speed aircraft. Bybalancing so that the products of inertiaare zero, the possibility of flutter occurringis reduced. Flutter, if allowed to increase,may ultimately lead to loss of a wing orcontrol, and is caused by interaction betweenstrbctural and aerodynamic forces.

The amount of balancing carried out onthe controls depends on the type of aircraftand its duties. A fighter aircraft requiresto be more responsive on the controls, andalso the pilot should be able to " feel " thecontrols, thus overbalancing must beavoided. The same reasoning applies to thestability of an aircraft as a whole, i.e., itis possible to make an- aircraft too stable.If it possesses great stability, the forcerequired to operate the controls to performmanoeuvres is increased.

Trimming TabsTrimming tabs, adjustable in flight by the

pilot, are usually fitted to the elevators andrudders. The ailerons are as a rule fittedwith tabs adjustable only on the groundand usually fitted to one aileron only.

The function of the trimming tabs is toallow the aircraft to be flown withoutcontinual pressure by the pilot on thecontrols. It is very rare for the centre ofgravity of an aircraft to remain stationaryduring a flight of any great duration. Con-sumption of petrol, dropping of bombs,movement of passengers, etc., cause the

centre of gravity to change its position. Ifthe tail became light, it is obvious that thepilot will have to pull the control columnback towards him and thus brirg the taildown. This means that he has to exerta continual pressure in order to maintainthe aircraft in its normal position.

By fitting trimming tabs, the camber ofthe control surfaces may be altered, thuseither increasing or decreasing the lift. Inthe case mentioned in the previous para-graph, i.e., tail tending to move upwards,the pilot would operate his elevator trim-ming tab control so that the tab moves

downwards.This causes theelevator tomove slightly

angle. upwards,,givinga resultant liftdownwards,pulling the taildown to its

Fig. 5.-Diliedra

originalposition.

Trimmingtabs are some-

times also fitted so that they act in a similarmanner to the servo control mentioned previ-ously. In this case they are connected up sothat they move in the opposite direction tothe control to assist in its operation.

Control ProfilesThe profile of the controls is important,

and as a general rule it has been found thatthose with a high aspect ratio are the mostefficient. By a high aspect ratio it is meantthat the span is great compared with the

BalancingPortion Hinge Line

BalancingWeight

Fig. 6.-Balanced controls.

chord, i.e., the length -width ratio is fairlyhigh.

The actual profiles adopted vary, and eachaircraft firm appears to favour its owndevelopment: in many cases it is possibleto identify an aircraft by the shape of itstail unit.

The positioning of the controls is alsoimportant, as the farther away they arefrom the aircraft's centre of gravity thegreater their effect. If the fuselage is shortand stubby, then large areas are required, orif it is a long, slim aircraft then the controlsurfaces may be reduced in size.

-During a spin the rudder control is oftenblanked off by the tailplane and elevators,thus making it ineffective. Consequently,on some aircraft the fin and rudder or thetailplane and elevator are movedforward or aft to avoid thistrouble.

The total areas of the controlsvary, but .approximate figures areas follows: Ailerons, so per cent.of the wing area, tailplane andelevator 15 per cent., and fin andrudde: 8 per cent.

Auto -RotationAn interesting occurrence whicis happens

when rolling with the angle of incidence ator near the stalling angle is auto -rotation.Normally, when a wing drops, the increasedlift tends to right the aircraft. However,when the critical angle is exceeded the liftingforce is not increased, but is decreased.This tesults in the roll being increasedinstead of being damped out. Consequently,unless the pilot takes action, a constant Iota -don will develop which is ternied auto -rotation. The rate of rotation can actuallybe calculated mathematically.

Control ConstructionThe movable controls are all constructed

on similar lines as a general rule. A singletubular spar to which the ribs are attachedand finally a fabric covering, is the usualpractice. The ribs may either be built upor made from pressings. Diagonal bracingmembers are frequently added.

As an alternative to tubular spars, whichare usually steel, built-up light alloy sectionshave been utilised.

Welding has been applied for control con-struction, but it is not used to any greatextent, although it is quite satisfactory fromthe strength point of view. As regardsweight, it has been found possible to pro-duce lighter controls by welding than ispossible by the usual methods.

The fixed portions of the controls, i.e.,tailplanes and fins, follow the usual wingmethods of construction.

Control OperationThe elevators, ailerons and rudder are

operated by the pilot by means of twocontrols, i.e., the control column and therudder bar. The control column is verticalin the neutral position and controls both theailerons and elevators. Forward and aftmovement causes the elevators to movedownwards and upwards respectively, thuslowering or raising the nose of the aircraft.

Sideways movement of the control columnoperates the ailerons. A movement to theright causes the right wing to drop by rais-ing the starboard aileron and depressing theport aileron.

The rudder bar, operated by the pilot'sfeet, moves the, rudder over to the right,when a right-hand turn is required, andthe rudder is moved to the left by the pilotpushing the left-hand side of the bar for-ward.

A typical control system for the elevatorsis illustrated in Fig. 7, the other controlsbeing operated in a similar manner. In thiscase cables are shown, but push-pull rods areoften utilised. Cables are cornparativeiycheap, but tubes have the advantage thatthey do not stretch and only require onelength instead of the two lengths of cableneedd to "transmit loads to raise or lowerthe controls. Turnbuckles are required foradjustment of the cables to take up the slack.

From the diagram it will be seen 12iist thecontrol column transmits its moven-eat via aconnecting rod to a vertical lever. 1hecables are attached to this lever and passto the control lever on the elevator. It willbe noted that the wires are crossed so asto give movement of the elvator in thecorrect direction.

Pulleys and fairleads are used to guide thecable round any obstruction.

Control Column

Lever Hinge Control

Fig. 7.-Control system.


The "Volkswcz enThe German Light Aid Detachment Vehicle, Which is Based on the German People's Car

(Continued from page 152, February issue)

THE connecting rods are made fromsteel stampings, a thick layer of bear-ing metal being run direct into the

big end. The bolts securing the connectingrod caps have hexagon socket -type fittingson the heads.

The aluminium crankcase is made in twohalves, and is split on the vertical centreline through the main bearings ; the halvesare secured together by means of bolts andstuds. An oil sump is formed integral withthe crankcase ; the underside is generouslyfinned. In addition, the casing serves asa mounting for the various accessories, suchas the dynamo, oil cooler, blower equipment,etc.

A single camshaft driven at half enginespeed by single helical gears from the crank-shaft runs direct in the aluminium crank-case, and actuates the overhead valvesthrough push rods, each cam operating tworods. The whole of the valve gear ispressure lubricated.

The distributor is mounted on top of thecrankcase, and is driven by spiral gears fromthe rear end of the crankshaft. The drivenshaft consists of the spindle, and gear andcam for operating a petrol pump, and ismade from a steel stamping, which ishardened and ground. It is supported atboth ends, and runs directly in the crank-case, the gear end thrust also acting againstthe crankcase facing.

The petrol pump is an A.C. diaphragmtype, mechanically operated, mounted on theleft hand of the crankcase, on a neat mould-ing which also houses the .operating rod.A single downdraught " Solex " carburettoris fitted. This is connected to the cylinderhead by an extremely small -bore inlet pipe,which has a central hot spot. The latteris obtained as the result of pressure pulsa-tion which causes the exhaust gases to flowpast the hot spot.

The crankcase has an extension whichprovides a saddle mounting for the dynamoand also forms a convenient oil filler orificeon account of its hollow construction. Thedynamo is driven by means of a " V "-shapebelt, adjustment being provided.

The flywheel is a steel stamping withintegral starting gear teeth, and is spigotedto the end of the crankshaft and driven by

four dowels.by a single

It is secured to the crankshaft .hollow so as to include a self-lubricatingcentre bolt, the latter being bush for the clutch shaft. No locking device

is provided.

Crankcaseis an aluminium alloy sand

casting, built in two halves, the joint passingThe era:1k( ase

myoINCHESeeS 5 6 799 HD if IS

% 4 5 I0 11 . IS . 20 0 25 xi° » 30CENTIMETRES

Longitudinal section of engine.

Body plan of car

CENTIMETRES

oo


vertically through the centre lines of boththe main bearings and the camshaft bearing-the camshaft itself running directly in thecrankcase. An oil sump is formed integralwith the crankcase, of fairly wide and shal-low proportions so as to afford maximumground clearance, fins being cast in alongitudinal direction on the underside.(Provision is made for a detachable gauzefilter which is centrally mounted on the baseof the sump.) A large diameter flangeformed at the flywheel end is utilised as anengine mounting face with spigot fitting.Lubrication is through drilled oil ways inthe crankcase. Platforms on top of thecrankcase carry the oil cooler, dynamo andblower equipment.Engine Unit Mounting

The engine unit, including the gearboxand axle differential, is suspended on rubbermountings arranged to permit a smallrotational movement of, the unit about anaxis passing through its centre of gravityand coinciding with the centre -line of thevehicle in plan. This is arranged to absorbthe torque reactions, but owing to the half -swing axle type of suspension employed, itis not considered good practice. Interactiontakes place between the half axle and the

engine due towheel movementor roll and enginereaction ; conse-quently theengine movementis restrained tosome extent andlimits the valueof the rubbermounting.

Comparativelysmall movementis permitted onthe enginemounting a n dthis may have

yo. COOLER

been purposely designed, having regard tothe interaction. The tension on the rubbermounting is adjustable. The engine mount-ings consist of two rubbers vulcanised on asteel bracket bolted to the prongs at the rearend of the backbone fork which, in turn,supports the engine around the portion of

the crankcase adjacentto the flywheel. Thisforms the main supportfor the engine unit onthe backbone, one otherpoint of attachmentbeing situated at theforward end (or nose)of the unit. A rubberring type mounting isfitted, acting principallyas a location for theunit. It is housedinside a casting at thecentre of the tubular..cross membar.

L

Oiling diagram for engine.

Nt.

Horizontal cross-section of engin:.

192 NEWNES PRACTICAL MECHANICS Warch, 1944

Making. a Success ofBetter Prints from Your Negatives.

AT this season of. the year some of themost popular lectures of photographicsocieties are those relating to the

making of better prints, the improvement offaulty negatives, wrinkles and dodges inprinting, and similar talks by those whohave had much experience, and are willingto pass it on to their fellow members. Thework is such that it can be done quiteeasily at any time, but, most of us relegateit to the long, dark evenings and when thecamera is not so much in use, taking newsubjects and adding to our collections ofnegatives.

He is, indeed, a fortunate amateur whocan claim to get too per cent. good results ;it is not always easy to accurately judgecorrect exposure, and mistakes have beenknown to occur in calculating developmenttimes, but the careful worker will note theseresults, and will put the negatives on one sideuntil he has time for some after treatmentto be given to them.

"After Treatment"It is this " after treatment " which forms

the basis of the popular lectures and demon-strations, and it is mostly concerned withintensification and reduction of the image ;there are, of course, other ways of obtainingbetter prints, such as the use of the rightgrade or surface of printing paper forobtaining special effects, but as this involvesthe purchase and stocking of more than onevariety, and as it is so difficult to obtain evenone grade, we must not consider it at .thistime, --but rather leave it till the happy daysreturn when we can get all we require.

Let us therefore give some thought to thetreatment of our faulty negatives by chemicalmeans ; the processes are such that we canall do them quite successfully without anyprevious experience and, fortunately, thechemicals are obtainable even in these daysof restrictions.

Intensification, as its name implies, meansincreasing or building up the image so thatit becomes rather denser, and produces amore defined image in the positive print. Itmust not be thought by this that in the caseof an under -exposed film you will be ableto " introduce " by intensifying some detailsof the subjects that are absent as the resultof wrong exposure. The image in anynegative is the direct action of light on thesilver contained in the emulsion and reactedupon by the developing solution if thisaction and reaction have been sufficientlypowerful to produce an image, even a faintone, then i.. is possible to add to, or Coatover, that image and so make it denser.

Re -developingThe process known as re -developing is

probably the best for illustrating the build-ing up of the image ; it is a two -bath method,' and first the negative is immersed in ableaching bath where the image almostvanishes As a matter of fact a chemicalreaction takes place which changes the imageinto a compound salt of silver and chromititn.After washing, the negative is transferred toa clean working developer such as anymetol-quinol formula, and this causes theimage to reappear in its " black " stage, andwith added depth. If, on printing, it isfound that further intensification would beadvantageous, then the process, both bleach-ing and redeveloping, can be repeatedwithout risk or damage being incurred.

The bleaching bath is made as follows:-

Your PhotographyBy JOHN J. CURTIS, A.R.P.S.

" A " Potassium bichromate 24o grainsWater so ounces

" B " Hydrochloric acid(pure) s ounce

Water to make so ouncesThese two stock solutions will keep

indefinitely, but do not mix " A " and " B "until you are ready to use as the mixturequickly deteriorates. It must be noted thatintensification, or rather the degree ofintensification, is considerably influenced byaltering the proportions of " A " and " B "when preparing the bleaching bath. Fornormal work take one part each of " A "and " B " and add six parts of water ; forvery thin negatives requiring much intensi-fication, mix one part " A " to one quarterpart " B " and six parts water. For re-developing the film any of th,e standardmetol-quinol formula may be used.

Uranium BathThe process which appeals to a very large

number of amateurs chiefly because of its

" B " and add one part acid acetic. Washin still water.Reduction

So much for improving negatives that aretoo thin. We must now give some thoughtto those that are too dense, or thick, andrequire some of the image or silver depositto be cut away, or reduced. For our pur=pose we will consider two types of negativeswhich require reduction, and let us bear inmind that this process is for reducing thetime of printing and also to improve thegradation of the negative.

For negatives which give prints that aretoo " hard," due to under -exposure andover development, the best bath is thatknown as the Persulphate Reducer ; thissolution acts first on the heavy high -lightdensities, such as the sky or solid whites,before it starts reducing the shadow details.You will therefore recognise that thisselective action reduces not only the depositbut also the excessive contrast. Take 5ograins ammon. persulphate, dissolve this in

A print front an intensified negative.

simplicity and its great efficiency is theuranium bath. Its action. is to coat thewhole of the film with a deep orange tint ;it would appear to have a selective action, forit seems to deposit more heavily on the-actual image than on those parts whichhave little or no silver image to beintensified. There is a very decided advan-tage to be gained by the use of the uranium,bath. If for any reason you desire to removethe orange tint, place- the negative in a bowlof water, and in a very short while it willbe found to have regained its original colour.For some 'mimeses, such as enlarging on aspecial grade of paper to secure a particulareffect, a thin negative is required,- but thatsame negative would be useless for contactprinting- o-1 say, some gaslight papers ; youwill therefore see how useful the uraniumbath can be for such negatives.

I will give you the formula as mentionedin one of our leading text -books; but I findit is more economical to buy a bottle ofJohnson's Uranium Intensifier ; it keeps welland is sufficient for quite a number of films.The formula is

A " Uranium nitrate 5o grainsWater to make 5 ounces

" B " Potass. ferricyanide 5o grainsWater to make 5 ounces

For use take four parts each " A " and

4 ounces water and add two drops acidsulphuric.

This bath will only function when freshlymade. Wash the negative well, then pourthe solution over it, and rock the dish theWhole time. In a short while a milky depositwill appear in the solution-this indicatesit is working-continue rocking for abouthalf a minute for slight reduction, increasingthe time if further reduction is desired.

Should the milky deposit not appear intwo or three minutes throw the solutionaway and make fresh, if very considerablereduction is wanted make a fresh bath whenthe one becomes opalescent. When thenegative is sufficiently reduced rinse itquickly and. place it in a weak hypo bath(4 ounce td so ounces water) for just oneminute, and then wash it thoroughly.

For negatives which give prints that aretoo flat, showing considerable over exposure,a bath that will increase contrast and at thesame time reduce the general density isnecessary and so we use the process knownas Howard Farmers.

Make the following two solutions:-" A " Hypo 24 ounces

Water to make 20 ounces" Potass. ferricyanide t ounce

Water to make so ouncesThese two solutions keep indefinitely but


must only be mixed just when you are goingto use the bath.

To each 3 ounces of " A " add + ounce of" B " (more of " B " can be added, if quickreduction is wanted). Use this at once, for thesolution becomes useless in a few minutes.It is of a lemon -yellow colour and as soonas it becomes a blue-green it is useless.Reduction takes place very rapidly so thatit is necessary to watch the effect frequentlyduring the course of the first two or threeminutes.

After sufficient reduction has taken place

wash the negative in running water for soto 15 minutes, and stand it to dry.Importance of Cleanliness

With these two intensifiers and tworeducers there is no reason why you shouldnot considerably improve the majority ofthose negatives which give" poor prints ; thework is quite simple and very interesting,and a knowledge of the processes will befound helpful to you as you progress withthe hobby. There are, however, certain ruleswhich apply equally to all these after treat-ment processes. Cleanliness is of great

193

importance, and both dishes and measuresmust be made clean after using, and thenegatives well soaked before commencingthe wont. Soak all negatives in clear waterfor at least an hour beforehand as this willserve two purposes ; it will free any hypowhich may be present, and it will ensureeven action over the whole of the film'ssurface by the chemical solution. Unevenaction will perhaps spoil the negative ratherthan improve it. Finally, do not overworkthe solutions ; it is cheaper to use a freshbath than to spoil one film.

Aero-en hie FuelsTheir Essential Characteristics Explained. By D. J. H. DAY, B.Sc.(Eng.).

IT is not generally realised that the fuelused in the high performance enginesof the R.A.F. differs vastly from that

sold at the petrol filling stations for use in'the family car. There are many points ofdifference between the fuels, the main dif-ferences being in octane number and vola-tility. Other points which must be care-fully watched in aircraft fuels are theirfreezing points, specific gravities, and percen-tages of gum and free sulphur. It is notwithin the scope of this article to deal withthese latter points, so we will confine our-selves to the main differences.Octane Rating

The first and probably the best knownproperty of a fuel is its anti -knock oroctane rating. The octane rating of the fuelindicates its resistance to detonation, and,indirectly, therefore, the possible poweroutput of the engine concerned. Detona-tion is shown by a knocking sound likethat produced by a sharp ringing blow uponthe metal of the cylinder. This is causedafter the ignition point by a wave of highpressure travelling at a great speed throughthe compressed gas and impinging withintense local force upon the metal of thecylinder wall. The same noise is producedunder similar .conditions by the sudden andhigh local, pressure produced under ahammer as it strikes an anvil. This highpressure wave travelling through the burn-ing gases is generated when the rate ofburning of the fresh gases becomes enor-mously accelerated and becomes virtuallyspontaneous instead of being comparativelygradual. - The physical causes of detonationhave not yet been finally established, andare outside-- the scope of this article. Itmay be said, however, that detonation isaffected by the fuel employed, the compres-sion ratio and the design of the combustionchamber. Since the design of the combus-tion chamber is bound up with the designof the. engine, we may say that the com-pression ratio determines the point ofdetonation for any particular fuel, and alsothat the higher the anti -detonation or octanerating of the fuel, the higher the compres-sion ratio that may be employed. -

In an aero-engine prolonged detonation,however slight, must be avoided, as itcauses piston -ring sticking, with its result-ant loss of compression, and eventually itwill result in burning of the piston crownand consequent complete failure of theengine. It is essential, therefore, that theengine manufacturer should know the octanenumber of the fuel to be used in the enginein order that the boost pressure and com-pression ratio may be determined to ensurethat the maximum power may be developedwithout fear of detonation.Volatility

The second requirement of aero-engine

fuel is that it should be of a high volatility.Volatility, or the ability of the fuel toevaporate, is determined by distillation ofa sample of the fuel under standardisedconditions.- This volatility of the fuel isimportant for a number of reasons, includ-ing ease of starting, good distribution ofmixture and prevention of carburettor icing.Aero-engines are usually more difficult tostart than motor -car engines since, owingto their size, they are difficult to turnrapidly, consequently a great deal of heat islost during the compression stroke, whenthe major part of the evaporation and mix-ture of the fuel with the air under startingconditions takes place. further, on accountof size, the induction pipes are necessarilylong, which permits condensation of thefuel from the mixture until the engine iswarmed up. It will be clear, therefore, thatthe more volatile the fuel, the better theevaporation at low temperatures, and conse-quently the easier the starting.

In a multi -cylinder engine it is fairly easyto ensure that each cylinder receives the.ame weight of mixture, but it is moreimportant that each cylinder should receivethe same amount of fuel. It has been foundthat the distribution is largely dependentupon the amount of vaporisation that takesplace in the carburettor. With a very wetmixture the chances of had distributionare very greatly due to the fact that thesupercharger, acting as a centrifugal separa-tor, throws more liquid fuel tee one side ofthe volute than the other.

The volatility has an important bearing onthe icing up of the carburettor ; in a petrolengine the fuel is evaporated partly in thechoke tubes and partly in the inductionsystem, a proportion of the necessary heatto cause vaporisation of the fuel is suppliedby the air entering the carburettor and,generally speaking. the temperature of theair drops in proportion to the amount offuel evaporated. It will be seen, therefore,that if a large amount of fuel is evaporatedin the carburettor a big temperature dropwill take place, and the water in the humidatmosphere will separate out in the formof ice. Consequently, a high volatility fuelwhich requires less heat to cause vaporisa-tion will materially assist in keeping thechoke tubes free from ice.Specific Gravity

For all normal purposes the specific gravityof the fuel has very little influence on theperformance of the, aircraft, since the workdone by the engine is dependent on theamount of heat obtained from the fuel, asopposed to the weight of fuel burnt. In thecase of aircraft designed for long-rangeoperation it would be advantageous to usea low gravity fuel, owing to the greaternumber of heat units per unit weight oflow specific gravity fuel. This saving inweight may represent a considerable increase

in the bomb load which can be carried, oran improvement in the .take -off. On theother hand, where it is desired to obtain themaximum range from an aircraft withoutalteration to the volumetric capacity of thefuel tanks, it will be found advantageous touse a fuel having a high specific gravity inorder to accommodate the greatest numberof heat units per unit volume. In a case ofthis sort the load increase caused by theuse of the high specific gravity fuel willhave very little effect on the performance ofthe aircraft.Vapour Pressure

When fuel is heated, it tends to formvapour, the volume of which depends on thenature of the fuel. If the aircraft fuel systemis imperfectly designed, so that the fuelpipe becomes excessively hot, or if the fuel

sucked up to a considerable height in thefuel pipe so that the pressure in the pipeis low, the fuel in the pipe may start toevaporate. This tendency is greatly increasedby the lowered boiling point of the fuel ataltitudes under rarefied atmospheric condi-tions. The vapour thus generated mayaccumulate at a bend in the fuel line or ata filter and thus interrupt the flow of thefuel. Fuels having a low vapour pressureare therefore required to prevent thesetroubles in high -altitude aircraft.

Calorific Value and Latent HeatThe calorific value of a fuel is the heat

energy obtained when a unit quantity isburnt freely in the air, and consequently itis a measure of the power output of thefuel ; the greater the calorific value the lessthe weight of fuel required for a given poweroutput. In view of the fact that there is nota wide variation in the calorific values of thehydrocarbons used in aero-engine fuels, thisfeature is relatively unimportant. Sinceliquid fuels are evaporated before they areburnt in the combustion chamber, the latentheat of evaporation has a slight bearing onthe characteristics of the fuel. The latentheat modifies the nett calorific value of thefuel, since the latent heat of the water foundby condensation after combustion must besubtracted from the calorific value of thefuel used. Another effect of the latent heatis that it cools the fuel -air mixture as itenters the cylinder. The volumetric effi-ciency is thus improved, since, by coolingthe charge in this manner, a greater weightmay be induced into the cylinder with theconsequent result of increased power petstroke.

Thus we see that the fuel used in modernaero-engines must be very carefully blendedand chosen for its particular characteristicsaccording to the engines in which it has tobe used, and that a very strict watch mustbe kept on the specification of the fuelduring its manufacture if it may be usedwithout detriment to the engine.


Aircraft of the Fighting Powers. ByH. J. Cooper and 0. G. Thetford. Books ReceivedPublished by The Harborough Pub-lishing Co., Ltd. 78 pages of text,and several single and double pageillustrations. Price 2IS. net.THIS work, which is Vol. IV of the series

" Aircraft of the Fighting Powers,"must be used in conjunction with the

others if a complete record is to be kept of allthe military aircraft used in the present war.The present volume deals with the aircraftused by Great Britain, United States ofAmerica, Germany, Japan and the Union ofSoviet Socialist Republics. Each aircraftdescribed is illustrated with one+ or morehalf tones and either a full page or doublepage line drawing, which make the bookextremely useful to designers, students, andaero-modellers. The book is remarkable forthat accuracy of detail which makes it in -

An Electric Alarm ClockDetails of a Simple Conversion, Using an Ordinary Spring -driven Clock

DOES your alarm clock fail to wakeyou ? If you are one of the unluckypeople who cannot wake up, or one

of those who slip off to sleep again afterthe alarm -has wound down, then why notconvert your alarm into an electric one ?By these means you cannot fail to wake asa much louder ringing tone keeps on untilthe battery is exhausted, or until you get

Triangular sedion X .3"

to Platet bent toform as shown

obtained by using a wireless grid biasbattery ; this will last about seven to eightmonths. A light is also fitted so that whenthe alarm goes off the light goes on, andthe time can be readily ascertained whilstin bed.

The ClockcaseAlthough the dimensions of the clock -case

Alarm gong striker and other small parts to beremoved before commencing changeover

Fig. 1.-General view of clock, showing bulb mounting and caseassembly.

out of bed and switch it off ; or one canfit a pear switch and operate it whilst inbed, but if you're apt to drop off to sleepagain then dispense with this idea.

A general view of the converted clock isshown in Fig. t. A small electric bell isinstalled, but increased sound can be

{

Fig. 3.-View of underside, showing bell andbattery positions.

Iwo clsunkscrew holes

Fig. 4.-Detailsof battery clip.

in the case and contacts judged to get correctWorking position. After marking the posi-lions, the clock is removed and contactsscrewed on, using about yin. brass woodscrews. The battery clip is shown clearlyin Fig. 4, and is made from I / t6in. springsteel.

The circuit diagram is shown in Fig. 5if desired, the bulb can be omitted.

Terminals forconnecting onpear -switch

ID

Fig. 2.-Rear viezo of clock, showing arrangement of contactbrackets.

will suit most clocks, you might have tomake slight alterations for the round aper-tures back and front, also in the width ofthe case. The making of the case is indi-cated in Fig. r ; the aperture in the frontpanel must be a tight fit for the clock. Allnails showing can be sunk by using a finecentre punch and filled in with plastic wood,the work being finally glasspapered. Thebell and battery support board is then fixedto two triangular blocks which have beenglued into correct position and then screwedand glued to the sides of the casing. Mostalarm clocks have hinged keys, and these canbe readily made rigid by inserting part ofa match -stick, for it is on this key that the -contact will rest before being released whenthe alarm goes off, or when the key startsto unwind.

Electrical PartsThe contact bracket (a), made from brass

and seen in position in Fig. 2, must bean easy fit on clock -case. The clock is fitted

TestingTo test the alarm, set the hands to about

3.55, give about two turns on the alarmkey, then in five minutes' time themechanism will operate, causing the key tofree contact bracket (i), which completes thecircuit by dropping on to contact (2), thuscausing bell to ring and light to go on.

Bulb

Berlr'l

TerrnmcdsSwitch

Battery

Contact Ain (Bross)

-...,Double over ofend to form weight

Fig. 5.-Diagram of electrical connections.

valuable to both the " spotter " and air -conscious layman.

Beautifully produced on art paper,the bookmay be recommended as an authoritativework of reference on a subject of extremeimportance at the present time.

Fleet Air Arm. Published by H.M.Stationery Office, London. 128 pages.Price Is. 6d. net.Here is a book which tells of the rise of

Britain's Naval Air Power in a very interestingmanner. Prepared fix. the Admiralty by theMinistry of Information, the book gives alucid account of the various types of aircraftused by the Fleet Air Arm, its aircraft carriers,and some of the notable actions of the presentwar in which they have taken part. Graphic

accounts are given of the attack by Swordfishin Bomba Bay, Libya : Spotting for theFleet : the Second Battle of Narvik : TheTriumph at Taranto : The Battle of Matapan :Protecting the Convoys, and African Opera-tions. The story is told of the tracking downand the sinking of the Bismarck, and thefine work of the Desert Squadrons in theMiddle East. Naval aircraft have showntheir ability to work with the MerchantNavy across the seas of the world, and withthe R.A.F. in Great Britain, Malta and NorthAfrica. They have also fulfilled anotheifunction for which they were not originallyintended-co-operation with military forceson land. How Naval Aircraft supported theNorwegian Expeditionary Force, and co-;operated in the Madagascar campaign, is als?vividly described in the book. Thetext is illustrated with many strikingphotographs.


The Story of Chemical Discovery

195

Advent of the Alkali TradeAn Early Chapter in Industrial Chemistry

THL use of alkalis dates back to pre -Christian times, to the era ,of theEgyptians in which a substance

called " nether " was employed for washingpurposes and, also, for making glass.

The Arabians, too, cultivated a certaintype of seashore plant, the burnt ashes ofwhich, when dissolved in hot water, gave awhite sub3tance to which the name kali, or

James Muspratt (1793-1886).

al-kali was applied. The ashesof seaweeds were discovered tobe productive of this kali, also,and gradually, as the centurieswore on, the process of collectingand burning seaweed and 1 ixiviat-ing or extracting its ashes withboiling water rose to the import-ance of a veritable industry.

Almost to the end of theeighteenth century (the 'periodwhich coincided with the rise ofmodern scientific chemistry) theworld's alkalis were obtainedsolely from such plant or vege-table sources. The main alkali ofthat period was potash, whichalkaline agent was obtained by the evapora-tion of water in which wood ashes (potashes) had been vigorously boiled. The earlychemical workers seemed hardly to recogniseany difference between - their " potash "(potassium carbonate) and the analogoussubstance which we nowadays call " soda "(sodium carbonate). There was, indeed, noscientific foundation for alkali manufacture.The alchemists, of course, knew nothing con-cerning the true nature of alkaline substances,and even the early chemists experienced thegreatest possible difficulty in understandingthe essential 'differences between the variousalkaline substances. They failed to appreciatethe fact that the alkali from plant ashes(potash) was different from the alkaliobtained from seaweeds (soda).

" Fixed" and " Volatile " AlkalisThe early chemists satisfied themselves by

distinguishing between " fixed alkalis '(potash and soda) and " volatile alkalis "(ammonia and ammonium carbonate). Theyalso used the term vegetable alkali for thepotash which they extracted from the ashesof land plants and mineral alkali for the sodawhich they obtained from seaweed. Theformer term has come down to our owntimes, but it is, of course, a whollyunscientific one.

Into the complex narrative concerned withthe scientific unravelling of the alkali com-position question we cannot very well enterat the present time. Suffice it, however, tonote that during -the years when this once -vexed quegtion was being fought out byinvestigators in England and on the Contin-ent, the demand of alkalis was growing byleaps and bounds. New- industries werecoming into being. Older ones were beingoverhauled in the light of the then modernknowledge. Novel processes and technicalmethods were being designed. Numberlessnew products were being placed on theindustrial markets. All such activities,technical and industrial, necessitated thesupply of alkalis in one form or another.Indeed, it is a truism to state that the indus-tries of the world, or, at any rate, a large

Manufacture of ".salt cake" (sodium sulphate). Commonsalt being charged into the " salt cake pot?'

number of them, have been reared not onlyon iron and steel and engineering knowledge,but on alkalis as well, for without a plentifulsupply of the ubitiquous soda there are wholemasses of industry (paper -making, dyeing,bleaching, chemical, glass, soap, porcelainand dyestuff industries-to mention but afew) which would be unable to carry on atall.

The problem of alkali production was oneof the pressing matters which beset the earlyindustrialists in this country and on theContinent during the second half of theeighteenth century. There was a theory-prevalent, particularly, among the Frenchchemists-that common salt contained someelement or principle in common with someof the then known alkalis. Now, ordinarysalt was a very abundant material, so, that

eventually some of the more " advanced "thinkers in the early chemistry of the periodbegan to wonder whether it might be possibleto convert the almost universally plentifulmineral salt into soda and, thereforasimmediately, to satisfy the increasingdemands which were being made on thelatter commodity.

Salt into SodaThe notion of converting salt into- soda

grew apace. It appealed to the minds ofthe technical people of the period, so muchso that in the year 1775 we find the famousFrench Academy of Sciences offering a prizeof 2,400 livres (approximately Doo inmodern money) for a practicable means ofobtaining soda from common salt.

At this time there lived in the employof the celebrated Duke of Orleans a privatesurgeon and medical man named NicholasLeblanc. Leblanc happened to be a ratherbrilliant and original -minded individual.Although only 22 years of age, he had madesomething of a name for himself as a surgeon,and he possessed, also, a very great enthu-siasm for chemistry, a subject in which theDuc d'Orleans himself was pleased to dabble.

Nicholas Leblanc was the son of a black-smith. He was born at Ivoy-le-Pre, France,in 1742. In some way or other he gained

admission ,to the famous Schoolof Surgery in Paris. Eventuallyhe passed out as Master ofSurgery, and he practised as amedical man for some time beforeentering the service of the Dued'Orleans.

The Leblanc ProcessLeblanc, in the Duc d'Orleans'

laboratory, experimented 'forthree years before he at last hitupon the famous soda -makingprocess which was to bring himscientific celebrity-and, alas,social ruin !

He stated off by treatingcommon salt with sulphuricacid, a process ' which had

William Gossage (5799-1877).

196 NEWNES PRACTICAL MECHANICS March, 1944been known previously. The common salt(sodium chloride) was thereby converted intosodium sulphate, and, at the same time,hydrochloric acid gas was abundantly liber-ated. The resulting mass of sodium sulphate(" salt -cake," as it was afterwards technicallytermed) was mixed with charcoal and chalkand then strongly heated. This process gavea crude mixture of sodium carbonate andcalcium sulphide, which, on account of itscolour, came subsequently to be known as

black ash." The black ash was thenextracted with water, and the sodium carbOh-aie in that manner dissolved out and finallyplirified by recrystallisatiori.

Such, in its . essence, was NicholasLeblanc's soda -making process. But it nevergained for him the Prize of the FrenchAcademy of Sciences; for the year of itsintroduction (1789) was' also the one whichwitnessed the beginning of the FrenchRevolution. However, in September, 1791,the revolutionary " National Assembly " inFrance granted Leblanc a patent for 15 yearsfor his soda process, and, with the aid ofa few interested individuals (including theDue d'Orleans), he established a factory-the world's first soda factory.

Before long the Leblanc works were infull activity, and were turning out sodiumcarbonate from common salt at the rate ofabout five hundredweights per day.

For a couple of years or so Leblancprogressed fairly satisfactorily with his pro-ject, although his factory was never freefrom technical trouble. Social troubles arose,too. The acid fumes which poured out fromthe soda works polluted the neighbourhoodand gave rise to much dissention. But, worstof all, the French Revolution rose to itsheight and set the nation into aferment.

After the establishment of theFrench Republic, Leblanc, in1794, was ordered to resign hisfactory to the nation for thegeneral benefit thereof. It wasan early example of State control,that supposed panacea which, inour days, so many ill -formedminds so desperately hanker after.Nicholas Leblanc found himself(to use a modern expresSion) a" directed " man. His factorywas taken from him, and hereceived the miserable compensa-tory sum of £160 for it. It istrue that, some half -dozen years

Ernest Solvay.

later, when more settled conditions returnedto the country, his factory was given backto him, but bad treatment, ill -health andpoverty had completely broken his spirit, andin the early morning of January 16th, 18o6,he chose to end his increasing cares by meansof a pistol bullet.

Alkali -making in EnglandThe individuals who took up Leblanc's

process in England were more fortunate thanLeblanc himself, although even for them theindustrial enterprise proved anything but astraightforward one.

James Muspratt, a Dubliner, was the firstto set up alkali -making in England, onaccount of which fact he has been dubbedthe " Father of the Alkali Trade." A verysmall amount of soda Oad previously beenmade on the Clyde, but the industry hadnot been successful. Muspratt, however, in1823, erected a factory in Liverpool to manu-facture alkali by the Leblanc process. Thenthe trouble started. No sooner had Musprattgot fairly going than almost the whole ofLiverpool rose up in seething opposition tohis activities.

The reader will recollect that whensulphuric acid is heated with common saltat the commencement of the Leblanc processhydrochloric acid gas is liberated. It wasthis hydrochloric acid gas which caused thetrouble. From Muspratt's factory chimneyit spread over Liverpool like a white, corrod-ing blanket. Ultimately the Corporation ofthat city corbelled Muspratt to close downhis process and to seek a fresh site for it,which site he eventually found at Newton -le -Willows, not far away.

Another pioneer of the British chemical

in the fails of Ballyshannon would condensethe gas om my works," he is reputed tohave exclaimed. Nevertheless, so effectivebecame the "Gossage Towers " that, in theAlkali Act, which was introduced at a laterdate, soda manufacturers were rightly com-pelled to equip their factories with similarabsorption devices.

William Gossage laboured incessantly tofind a method of reclaiming sulphur fromthe " alkali waste " which was a by-productof the Leblanc soda process. The alkaliwaste, consisting, as it did, of impure calcium(lime) sulphide, presented a perennial prob-lem to the alkali manufacturer. It was afoul, stinking stuff, which was produced inlarge quantities and which rapidly accumu-lated in enormous dumps around the alkaliworks.

Ir--

Sacks of soda crystals awaiting transport from an alkalifactory.

industry had a similar experience. He wasilliam goSsage, a Lincolnshire man, who,

starting as a druggist's assistant, cameeventually to be one of Britain's foremostchemical manufacturers. Gossage was amore inventive individual than Muspratt.Consequently he endeavoured to abate thenuisance consequent upon the discharge offree hydrochloric acid gas into the atmo-sphere, and the means by which he effectedthis took the form of a long vertical towerpacked with coke, down which a steadystream of water was allowed to trickle. Theascending hydrochloric acid gas came intocontact with the water and dissolved in it,forining the valuable industrial commoditywhich we now know as " hydrochloric acid."

Gossar's TowersMuspratt, when he heard of Gossage's

invention, was sceptics'.. " Not all the water

Henry Deacon (1822-1876).

Although Gossage never com-pletely solved the problem, hecame very near to doing so, andhis continual researches formedthe basis of the more successfulsulphur -recovery process whichwas introduced after his time.

Henry DeaconHenry Deacon, born in London

in 1822, was another of Britain'sforemost soda makers. After astrenuous early career, Deaconfound himself installed asmanager of Pilkington's glassworks at St. Helens, Lancashire.Finally, in association withothers, he branched out asan independent chemical manu-

facturer at Widnes, the early home ofEnglish chemical industry. Deacon manu-factured soda, but he was not content toconsider that the troublesome Leblancprocess was the last word which had beensaid on the .subject. He experimented withother possible methods of alkali production,notably with a method of converting saltinto soda by means of ammonia gas:Unfartunately, however, success failed tocome Deacon's way in this particular respect.

Until the year 1872 Leblanc's process ofsoda manufacture reigned triumphant. Ntoother process was able to compete with it,in any way at all. But in that year thereWas introduced a new soda -making method,one which, within a few years, rendered theLeblanc process almost obsolete. It was aprocess due to a young Belgian chemistnamed Ernest Solvay.


The Ammonia -soda Processf Solvay's new process was based uponearlier -known facts-facts, indeed, whichHenry Deacon in his experiments had madeuse of. To convert salt into soda, Solvay.made a strong solution of salt which hesaturated with ammonia gas. He thentreated the ammoniated salt solution (brine)with carbon dioxide (" carbonic acid gas ")under pressure. A mixture of ammoniumchloride (sal -ammoniac) and bicarbonate ofsoda was formed in the resultant liquor. Theless soluble bicarbonate crystallised out, leav-ing the more soluble ammonium chloride insolution and thus permitting a simple andeasy separation of the two salts.

Relatively speaking, Solvay's " ammonia -soda " process was a perfectly clean one. Itgave rise to no obnoxious acid vapours andto no alkali waste. It gave a soda productof high purity. Moreover, it was a processwhich could be worked continuously andwithout frequent intermission.

The ammonia -soda process was first estab-lished in England by the late Dr. LudwigMond, who, towards the end of 1872, set

up a factory to operate it at Northwich,Cheshire, directly above the Cheshire saltdeposits. In partnership with a certain JohnBrunner (who was formerly an accounts clerkin an alkali works) he created the famous" Brunner-Monds," which, together with theUnited Alkali Co., Ltd., and several otherprominent chemical manufacturing concerns,ultimately became fused together as thenowadays celebrated and world -prosperousImperial. Chemical Industries, Ltd.

As for Ernest Solvay himself, the inceptionof his process and the technical failures anddifficulties which he encountered, nearlyruined him. But he lived in more settledand prosperous times than those of the ill-fated Nicholas Leblanc. With doggeddetermination he overcame difficulty afterdifficulty. Ultimately he accumulated greatwealth and lived " to sit above the salt " andto witness the fame and prosperity of hisprocess the world over.

The Cheapening of AlkalisAt the end of the eighteenth century, soda

crystals, obtained from seaweed (the so-called

197

"mineral alkali ") were sold for k6o perton. The introduction of the Leblanc processinto England by James Muspratt in 1823lowered the price of alkali soda to £18 perton. At the beginning of the presentcentury, soda, manufactured by Solvay'sprocess, sold at about £3 los. per ton, andthe following years saw an even lower pricestill.

Growth of the Alkali IndustrySoda, one of the first essentials of a thou-

sand industries, thus became, during thecourse of a century, one of the cheapest ofmanufactured materials. The British alkaliindustry, based on soda made from salt, roseduring the same period to the position ofone of the foremost trades in the. country.

Such was the eventual result of chemicalskill, scientific experiment, individual effortand persistent application. The rise of thealkali trade is, indeed, a veritable industrialromance, but, unfortunately, the story of itsdifficult yet successful career has not oftenbeen related.

Science Notes of the MonthFrcist PredictorA N ingenious instrument known as a

" Frost Predictor " is likely to provea great help to fruit growers and nursery -Men in the event of a spring frost. Inventedby Sir Henry Cunynghame, the instrumentresembles a garden thermometer, but isprovided with two tubes, one to measuretemperature, and the other the humidity ofthe atmosphere. If at sundown the " wet "bulb reading falls below the " dry," a comingfrost is predicted. Over a long period oftrial. warnings were given correctly 23 timesout of 24. While the war lasts orchardheaters must not be used, but the predictorwill enable fruit growers and nurserymen totake the necessary precautions in time toprevent damage to their crops.

Britain's New Transport 'Plane

PARTICULARSof the Avro York, the

only passenger and transport aircraftBritain has built since the war began, havenow been released by the Ministry ofAircraft Production. The Avro York wasconceived by Mr. R. H. Dobson, managingdireCtor of A. V. koe and Co., Ltd., Mr.R. Chadwick. their chief designer, and hisassistants.

Engines, wings, tailplane, fins and ruddersare identical with the Lancaster. Thefuselage is entirely different, being large andsquare, to accommodate bulky freight. Acentral fin has been added.

With a wing span of toift.and a length 'of 78ft. the York,fully loaded, weighs 3o tons.Top speed with four Rolls-Royce Merlin engines is

claimed to be 300 m.p.h., theeconomical cruising speed 220m.p.h., and maximum rangeover 3.000 miles.' Such is the capacity of thefuselage that four Jeeps can bedriven in under their ownpower. The size of the interiorof the fuselage offers oppor-tunities for the most comfort-able furnishing, and the spaceavailable provides seatingcapacity for 24 passengers in twobig cabins, with wash -rooms,lavatories and a buffet -kitchen.

cc Mars" Maiden TripTHE huge flying -boat " Mars entered the

U.S. Naval Service last month bycompleting her inaugural flight from SanFrancisco to Hawaii in a little over 13hours. " Mars " did the trip with a recordcargo, including 13,000 pounds of mail andwar materials. .She carried 20 passengersand a crew of 15, and is powered by four2,200% h.p. engines. U.S: Navy authori-ties, when announcing the flight, stated that20 more flying -boats of the same type arebeing built.

Greenwich Observatory to MoveTT is reported that 'Greenwich Observatory,4- the home of the " right time," is likelyto be moved. The chief reason for this isincreasing smoke in the locality which' makesthe Observatory's sunshine recording inaccu-rate. Already much' of the work of theObservatory is done elsewhere, partlybecause of bola damage, and partly forsecurity reasons. The magnetic work wastransferred to the Surrey Hills some yearsago, because of the electrification of therailway.

Fast Victory ShipsTHE first of the Victory ships-successors

to the mass-pioduced Liberty ships-was launched at Portland, Oregon, U.S.A.,last month. The ship, named United

Victory, will probably be in service shortly.Victory ships carry the same weight of cargoas the to,000-ton Liberty 'vessels, but arefaster -15 knots as against iI.

Rocket TargetACCORDING to a recent report front

America, the U.S. Army are using arocket -propelled target, which travels withthe speed of a fast 'plane, for training A.A.gunners at a camp in 'North Carolina. Thetarget, which is about sft. long, is launchedfrom a tower, and has an initial speed of450 miles an hour and a range of about2,200 yards.

Camp officers said that practice with thenew target improved to a marked degreethe accuracy of gunners, who fire at thetarget with machine-guns and cannon.

Transmitting Speech` by Light Ray

THE German Army has in use a fieldtelephone instrument which utilises a

light ray as the transmitting agent for speech.It is claimed that the use of light transmis-sion avoids the disadvantages of wires asused for the normal field telephone, and ofradiation to the enemy of messages sentby radio. By the use of filters, visible lightrays are stopped at night, and the apparatuscall be used in foggy weather. A light beamof constantly varying intensity is sent outand picked up by a receiver equipped witha telescope and photo -electric cell.

The new Avro York transport 'plane, particulars of which are kiven above,


Inventions of InterestBy It Dynamo"

Glass Cloth BagsTN these days when it is illegal for a trades-

man to wrap up certain goods in papera capacious bag or basket is an indispensablearticle of the housewife's shopping equip-ment. It is therefore fitting that two ladiesshould be included among the applicantsfor a patent in this country for a bag ofglass cloth.

The idea is not unprecedented, since ithas previously been proposed to make sand-bags from glass cloth and to manufacturetranslucent containers of glass fibres.

The invention in question is a flexiblebag, the walls of which are of glass clothand are interconnected by stitching bymeans of a vitreous thread. The intercon-nection, if preferred, may be effected byfusion or by affixing by fusion patches tothe glass cloth.

When the bag is to be furnished witha handle, there may be attached to it bylacing through eyelets, cords or ropes com-posed of glass fibre strands fashionedsimilarly to cords or ropes of vegetable fibre.

The fabric of these bags may be treatedin such a manner that they have the appear-ance of natural vegetation. The glass clothmay be coloured either on the surface orby incorporation in the glass of colouringmaterials. If desired, it can also be coatedor impregnated with proofing medium ; forexample, a quick -drying oil, such as linseedoil.

It is affirmed that this bag is imperviousto moisture, non -inflammable, and proofagainst rot, bacteria, fungus and vermin.And it is adapted to serve a purpose forwhich the use of textile fabric bags has notpreviously been contemplated ; it may actas a container for corrosive materials.

Ideal Bricks

AFTERthe war the brave new world

which . we all hope will material-ise will undoubtedly include a vast numberof new houses, if not ideal homes. Thismakes appropriate any really useful idea inrelation to building.

With a view to provide effective buildingconstruction, an inventor has designed a newbuilding material. His object has been todevise a product reasonably light in weight,porous and one which is a good insulatoragainst sound penetration and variations oftemperature.

A further object has been to produce amaterial which is non -inflammable andvermin and white ant proof.

Additional characteristics aimed at arestrength, flexibility and a substance whichcan be sawn and into which nails and screwscan be inserted.

The inventor maintains that it is alsodesirable that such a material should notshrink unduly in setting nor expand or con-tract to any great extent owing to changesin temperature. It shoUld also take plasterwell, and finally, the material should bereadily moulded into shape.

The originator of this new buildingmaterial believes that his device realises theabove -mentioned desiderata.

His invention' consists of a lightweightmaterial which comprises a vegetable oranimal long staple fibrous substance, such ascoir, hemp, jute, wool, hair and other longstaple fibre normally used in industry, or

in the textile trade. This is impregnatedwith sulphate of aluminium and one of thefollowing: sodium carbonate, zinc oxide orcalcium carbonate, and it is caused to adhereand form a compact mass by means ofPortland cement or other cementing material.

The information on this page is speciallysupplied to " Practical Mechanics " byMessrs. Hughes & Young, Patent Agents, of7, Stone Buildings, Lincoln's Inn, London,W.C.2, who will be pleased to send free toreaders mentioning, this paper a copy of theirhandbook, " How to Patent an Invention."

Paper -making Process

A NEW process and apparatus for the. manufacture of paper are the subjects

of an accepted application for a patent inthis country. The primary aim of theinventor has been not only to obtain an

Down in the depths at the County Hall is installed one ofthe finest air-conditioning plants in the world. Huge pipesstart their journey to supply clean, warm and fresh air to the

council chamber.

improved product but also to effect a savingof time and expense in the handling andtreatment.

The inventor points out that hitherto inthe manufacture of paper, raw materials havebeen placed in a mixer containing fibrousmaterials, such as cellulose wood pulp, rags,waste paper, etc. There have also beenadded ingredients such as glue, alum, coloursand some others in the proportions chosen

in each case and mixed with the fibres whilethe fibres were being beaten and hydrated.

This process, however, it is stated, has thedisadvantage that, although fibres of differentkinds are mixed, all of them receive the sametreatment in equal degree and during thesame time. A more satisfactory result issaid to be attainable by treating each kindof fibre independently. And this is themethod adopted according to the inventionwhich it is desired to patent.

In the case of the new process, thedifferent fibres are individually treated tohydrate and refine them. Quantities of thepulps that are to form the constituents areintroduced into a measuring tank havingmeans whereby the quantity of each pulpcan be measured.

The pulps are then intimately mixed ."together with sizing material prior to beingfed directly, or after refining, to the feedtank of a paper -making machine.

Magazine for 'Planes

MILITARYaircraft

obviously needaccommodation for am-munition. As space in anaeroplane is strictly,.limited, the storage mustnecessarily be as compactas possible. This pointhas been borne in mindby an inventor who hasdesigned an arninunitionbox or magazine for tilemachine-guns mountedin a 'plane.

His idea is a boxlocated close alongsidethe guns so as to extendpractically parallel withthe gun barrel. This willhouse a number of super-posed lines of cartridgesarranged in belt orflexibly linked -up formextending backwards andforwards within` the box.

A longinidinal shallowchannel extends along theUpper part of the boil,forming an- outlet guide.Along this the line ofcartridges is adapied tobe fed from the box tothe gun. ,

Besides being appropri-ate for aircraft, theinvention is suitable for.other purposes in whichit is imperative to mini-mise space for ammuni-tion, or to operate gunsfrom remote cqntrol. Itis, however, particularlyapplicable for use wherea number of machine-

guns are mounted close togethei side byside in the wings or other convenient partsof an aeroplane.

DICTIONARY OF METALSAND ALLOYS

10/6 or 11/- by post fromGEORGE NEWNES. Ltd. (Book eapt.), TowerHouse, Southampton Street, Strand, London,

W.C.2.

March, 1944 NEWNES PRACTICAL. MECHANICS 199

Seaweed ExtractionSEAWEED constitutes one of the few

present-day raw materials which arefreely available for the taking. Quite

apart from the large masses of this materialwhich are washed up annually around thecoasts of the British Isles, the oceans of the

''world must, in the aggregate, contain colos-sal amounts of the various seaweed species.Yet among the raw materials of moderncivilisation, seaweed, the universal and inter-national harvest of the marine depths, is averitable Cinderella. After nearly a centuryof some economic importance as an importantiodine source, seaweed, apart from havinga few minor and localised uses, is, atpresent, a neglected material, a substancewhich has been little exploited in respect ofmodern demands and developments.

Seaweed is really a highly interesting and,in many ways, a remarkable and uniquematerial. It is interesting in regard to thenumber of useful substances whith can beextracted from it ; it is unique in consequenceof its property of absorbing iodine from sea-water . and concentrating this valuableelement within its own tissues.

During the stormy spring months, greatquantities of deep-sea weed are driven up onto the western coasts of France, Ireland, andScotland. For years, local workers havecollected the weed and have burned it inheaps at as low a temperature as possible,the ash being termed " kelp " in Britain,and " varech " in France.

During the eighteenth century, burnt sea -Weed or " kelp " was the only source ofalkali in Great Britain. Kelp production,therefore, in those days, was an importantoccupation. When, however, the mass -production " chemical " methods of alkaliproduction came into operation about 1840,kelp ceased at once to be of any importancefor alkali manufacture, but, for a numberof years, it was used as a source of iodine.Nowadays, of course, all the iodine suppliesnormally come from the vast nitrate

_ deposits in Chile, the iodine therefrombeing derived in the form of sodium iodate.

During the progress of the last century,therefore, the seaweed industry, in conse-quence of the loss of its alkali and its iodinemarkets, has dwindled away almost to

The Promise of a New Industrynothing. In spite of this, however, it wouldseem that the industry has not been killed,but that it is, at present, merely in a dormant

Common seaweed found everywhere around theBritish coasts suffices for many interesting

experiments in seaweed extraction.

condition, awaiting a resurrection to a newlease of life.

Seaweed Iodine.Before considering such possibilities of

revival, some information relating to the

Crude alginic acid ; a thick, gelatinous product obtained fromcommon seaweed.

Cleaning the seaweedprior to laboratory

processing.

occurrence ofiodine in seaweedmay be of interest.Iodine is presentin seawater to theextent of abouto.00t per cent. Itis present in sea-weed, however,particularly in thedeep-sea weed, tothe extent of 0.5per cent. In someway, therefore, allspecies of sea-

weed possess the remarkable property ofbeing able to filter out the iodine from theseawater. How they effect this operation istotally unknown at .present, although futureresearch may reveal the chemical mechanismof the process.

Iodine is obtained from " kelp "-the ashof seaweed-by extracting it with boilingwater. The iodides, carbonates, chlorides and.sulphates of potash, sodium and magnesiumgo into solution, and by subsequent carefulcrystallisation it is possible to remove themajority of the carbonates, chlorides andsulphates, leaving the much more solubleiodides in the remaining " mother -liquor."This latter is then concentrated down tofairly small bulk. Concentrated sulphuricacid is added to it, together with sotne man-ganese dioxide, and the mixture is carefullydistilled. Violet fumes of iodine arise, andthese are condensed in a cooled receiver.Approximately Io-I2lb. of iodine is obtainedfrom a ton of carefully -burnt kelp by thisprocess.

The process is capable of being imitatedon the small scale in the laboratory, yet it isseldom successful on such a scale. Theseaweed must be ashed at the lowest possibletemperature and in closed vessels in orderto prevent the escape of the very volatileiodine. Furthermore, a large amount of thekelp has to be extracted in order to obtainsufficient " mother -liquor " from which toobtain the free iodine by the sulphuric acid -manganese dioxide distillation process.

In view of thealmost uhlimited de-posits of sodium iodatein Chile nitrate de-posits, the extractionof iodine in any shapeor form from seaweedwill hardly ever be-come a commercialproposition a g a i n,unless, of course, somemuch simplified modeof obtaining t h eelement from the weedcould be devised.

Iodine is by nomeans the only valu-able product whichcan be obtained fromall classes of sea -weeds. A certaintype of weed is foundon the west coast ofIreland. It is knownas " carrageen moss."When this material isboiled with water, it

resolves almost completely into a thick jelly.This " Irish Moss," as it is often called, stillhas its commercial uses iii pharmacy, and asa thickener for colours in the calico -print-ing industry. In some parts of Ireland it israther extensively used as a food, althoughrecent scientific tests have demonstrated thatit possesses no food value worth speakingabout.

A curious thing about this extract of IrishMoss is that it tends to prevent the clottingof blood. Its chemical composition is un-known, but it has been shown to contain acomplex sugar-raffinose-together with anethereal sulphate of undetermined character.

Alginic Acid'One of the most interesting substances

which are obtainable from seaweed is alginic

200

!cid. This is a very viscous, sticky sub-tafice, which has already Num! some com-

e ipercial uses, and which holds out promise ofmany more.

It is not a difficult proposition to obtain aquantity of this substance on the small,experimental scale. The best procedure toadopt is the following:

Gather any of the usual varieties of Britishseaweed and wash the weed well in coldwater. Then cut it up into convenient -sized'pieces and gently boil the material with waterfor about r5 -2o minutes. This process willextract from the weed a brownish, viscoussubstance which is termed fucoidin. Thefucoidin .extract can be concentrated byfurther boiling, if desired, until the impurefucoidin is obtained as a reddish -brownsticky mass, which is completely soluble inhot water.

The extracted seaweed is then allowed tosteep for 24 hours in a dilute solution ofhydrochloric acid (spirit of salts), say one partof the acid in five parts of water. Duringthis immersion, the weed will change to asage -green colour. It is then removed fromthe dilute acid (which may be used again andagain for this operation) and rinsed well incold water in order to get rid of every traceof the acid.

The next operation is to soak the acid -treated seaweed in fairly strong ammoniasolution (two parts strong ammonia to onepart of water) for a further 24 hours, theweed being frequently stirred. Use just asmuch of the ammonia as will cover the weedin the vessel. If too great a quantity ofammonia is used, the excess will merely bewasted.Ammonia Treatment

The ammonia treatment will result in thesage -green seaweed turning a dark brownand partially dissolving into a thick, brownishliquid. After 24 hours, the entire mass isstrained by sqUeezing it through a coarsecloth. The brownish liquid which resultsis a solution, more or less impure, ofammonium alginate.

In order to obtain the free alginic acid,the ammonium alginate solution is carefullyacidified with strong hydrochloric, which isadded a drop or two at a time. At one stageof this operation a gelatinous precipitate willform in the liquid. This is the free alginicacid. It should he filtered off, dried andpreserved for further experiment. It isinsoluble in water, but is freely soluble inweak (5 per cent.) sodium carbonate (wash-ing soda) solution, or in weak ammonia.

When to a solution of alginic acid insodium carbonate solution, a solution ofcopper sulphate is added a thick gelatinousprecipitate of copper alginate is obtained.By using solutions of zinc of aluminiumsulphate, the corresponding zinc andaluminum alginates can be obtained.

NEWNES PRACTICAL- MECHANICS March; 1944

These metallic alginates are quite inbol-uble in water, and, having that character,they are capable of forming excellent water-proofing substances. They still await techni-cal and commercial development in this andin other directions, although sodium algin-te solution (the solution obtained by dis-

Another common type of marine weed whichis suitable for the experimenti described in this

article.

solving alginic acid in sodium carbonate solu-tion) has been used -as a cloth dressing in thetextile industry.

Absorbed into wood, solutions of metallicalginates in organic solvents, such as naphtha,would not only render the material water -

Forcing crude alginic acid through a cloth bag in order to free itfrom remaining tissue.

Cutting up the sea-weed into small piecesfor extraction withsodium carbonate

solution.

resistant and rot -proof, but wouldalso give it pro-tection a g a in s tmildew, mould, dryrot, and bOring=beetle attacks.

An alternativew i y of makingalginic acid is tosoak the washedseaweed directly in5 per cent. sodium

carbonate solution. (5 parts sodium carbonatein 95 parts of water). This gives an almostblack solution from which impure alginicacid can be precipitated by the cautiousaddition of hydrochloric or sulphuric acid.

The chemical composition of thi:; curioussubstance, alginic acid, is yet unknown. Itcontains carbon, hydrogen and oxygen, theproportions of which correspond to theformula, C6I-LO, but it is almost certainthat the acid is very much more complex inmake-up than this, and that, in actual fact,it is composed of a large assembly of theseC,,I-180,; units, all strung up together likebeads on a thread.

Fucoidin, the boiling water extract of sea-weed, is an interesting material of unknowncomposition. It is highly gelatinous, and,as such, may be combined with various resinsto make bonding materials. All such uses;however, have been but little investigated,and, at present, are purely experimental.Laminarin

Another interesting product of seaweedgrowth is laminarin. This can be obtainedfrom the broad, ribbon-like seaweeds bybrushing the fronds of these weeds withdilute hydrochloric acid for four or five daysin succession. After this time, laminarinwill be formed as a white deposi: on thesurface of the fronds, which deposit canthen be scraped away and the underlyingsurface of the weed again treated for furtherquantities of this substance.

Laminarin has been given the chemicalformula (C6I-11,, , the " x " designatingan unknown number. In actual fact, lamin-arin is a sugar of complex composition. Itis one of the rarer sugars. When it isboiled with a little dilute hydrochloric acid,it becomes converted completely into glucose,C,141,206; One of the simplest of the natural

sugars.These same ribbon-

like seaweeds a r eusually an abundantsource of the muci-lage -like substancecalled fucoidin, forwhen they arechopped on a boardthey exude it pro-fusely. Fucoidin issupposed to be a verycomplex sugar - likecompound containingcalcium and sulphur.It should surely findat least a few uses int h e fast - developingworld of commercialchemistry.

Mannitol is alsopresent in the majorityof seaweeds, althoughits extraction is diffi-cult. Mannitol is acomplex alcohol.When pure, it is acolourless solid, hav-

ing a sweet taste. It is readily soluble inwater and, when oxidised, it becomes .con-verted into sugars. Whether mannitol willever be, commercially extracted in the futurefrom any varieties of marine weeds is adifficult question to pronounce on. Neverthe-less, this useful material is certainly presentin seaweed, and probably the discovery ofa practical process for its extraction willrender it an important product in the chemi-cal economics of the future.

Plastic from SeaweedSeaweed, when thrown into ditches or left

to lie in the open, gradually rots away Thefucoidin and the laminarin, the alginic acidand other products are sloWly broken downby natural oxidising agencies. This rotted


Four Men from the ProvincesMr. York, Mr. Bristol, Mr. Dover and Mr.

Cambridge live (not necessarily respectively)in the four towns of the same name. --

Mr. Dover lives in the town with the samename as that of the man who lives in York.The man who lives in Dover has the samename as the town in which Mr. Cambridgelives.

Only one of these four men lives in atown with the same name as his own. Whois he?

Down Our, StreetFour houses in our street are named

Whitefield, Blackfriars, Brownleaves andGreystones. They are painted white, black,brown and grey ; and their occupants areMessrs. White, Black, Brown and Gray.

Only one man lives in a house the nameof which suggests his own name, and onlyone house (not the same one) has a namethat suggests its colour.

The name of Mr. White's house suggeststhe name of the occupant of the housepainted black. The name of the grey housesuggests the name of the occupant ofGreystones. Brownleaves is painted white.

Who lives at Whitefield ?

Phoney 'Phones"You are aware," said Professor Crack-

brayne, that my telephone is on the Living-stone exchange. I have just discovered thatin dialling my own number, if I reckon thethree letter LIV according to their numberson the dial, that is, as 548, then the seven -figure number produced is a perfect square."

" By a remarkable coincidence," said hisfriend, Professor Nitwit, " my telephonenumber is the same as yours, although on a

product is not without its uses. By steepingthe rotted weed for a few days in dilutehydrochloric acid, all remaining traces ofalginic acid are precipitated, and any mineralsalts are extracted. The residual weedymaterial is then well washed in cold waterand boiled with sodium carbonate (washingsoda) solution of about 25 per cent. strength(25 parts of soda in 75 parts of water). Thistreatment of the weed gives a dark -brown oralmost black horny material which can betaken up on a trowel and placed into moulds,in which latter it will dry and set into ahard, impervious material. The latter can becut and sawn like wood, and, like wood,also, it will take a screw securely. Further-more, it can be planed, painted, varnished,and processed in other directions. Surely,' then, a use will crop up for this curiousmarine weed product, or for some combina-tion of it with resin, pitch, tar, bitumen, orwith one or more of the more modernsynthetic plastics ?

If ordinary seaweed is treated with 25 percent. sodium carbonate solution by beingallowed to soak in this solution for a week,and if, then, the solution is concentrated andmixed with a little formalin and tannic acid(or a soluble tan -bark extract), a highlyviscous- mass is obtained. This mass con-tains alginates and Ether complex compoundsor, rather, their interaction products withformalin and tannic acid. The importantpoint, however, is that, when mixed withproducts such as glue, shellac, resins, rubberlatex, bitumens, etc.,it is capable of beingconverted into oard-hard waterproof

material which is suitable for impregnatinginto fabrics, felts- and other absorbentmaterials. It can, also, be` used for the back-ing of linoleum and for compounding variouswater -repellant plastic and mouldingmaterials.

Here, again, however, little work hat beendone in this direction, so that this " sea-weed plastic " still awaits the investigatorwho will develop it thoroughly.

Various authorities have asserted that goodcellulose -substitutes are obtainable frommarine weed. Such is quite possibly thecase, although the question has never beenprosecuted to its full practical extent. Itdoes seem certain, however, that alginic acid,as obtained from seaweed, is capable of form-ing a thread. Here, therefore, probably liesthe germ of some future synthetic threadapplication, for there should be no greaterdifficulty with the production of an alginicthread or. of one composed of a metallicalginate than there was originally with manyof the present-day synthetic or artificialfibres.

Seaweed SodaThe only mineral constituent of seaweed

which is of any interest is soda. This canbe obtained in the form of its salts by thesimple hot-water extraction of seaweed ashor " kelp." But, of course, in these days,the commercial soda producers have farmore abundant resources of their importantand indispensible commodity than thatprovided by the humble yet ever-presentweed of the ocean.

In connection with the well-known iodinecontent of marine weeds, it should not beimagined that the iodine occurs in the freeor uncombined state in seaweed. Quite alot of modern research on the iodine contentof marine organisms has been conducted inrecent years, and it now transpires that theseaweeds, the sponges and the corals allstore up iodine in their tissues, the coralsexcelling in this activity, since they all con-tain approximately 8 per cent. of the valuableelement.

It has been proved that the iodine com-pound existing in coral is very similar to,if not identical with, the iodine secretion ofthe human thyroid gland, which vital gland,as is well known, functions as the controllerof the bodily processes.

The precise nature of the iodine com-pound or compounds in seaweed has notyet been ascertained, but it seems likely tobe similar to that occurring in coral and,therefore, related to the iodine compound ofthe thyroid secretion.

It is highly probable, also, that there existin at least some species of marine weeds andother vegetation, other compounds and sub-stances of great interest which only awaitdiscovery, extraction and elucidation. For aworker skilled in the methods and techniqueof organic chemistry, the subject of seaweedand its scientific extraction and processingforms one of much promise both theoreticallyand practically. It is a field of chemicalresearch in which there is, at present, little,if any, competition.

Probes and ProblemsMore Mental Nuts for You to Crack

(Solutions are given on page 206.)

different exchange within the London ten -mile radius ; and by reckoning the diallingletters as numbers I too arrive at a perfectsquare in the same way."

I want to telephone to Professor Nitwit,but have forgotten his number. Can anyreader work it out for me ?

Energy on the EscalatorThe escalator at my Underground station

is 88yds. long, and it travels at the rate of2 miles per hour. I myself can run up anordinary stairway at the rate of 3 miles anhour.

Being a little late for my train yesterdaymorning, I ran up the moving escalator.,How much time did I save by doing so ?

Services Dinner Party" We had a little Services dinner party

last night," said my friend Adams, strokinghis beard. " Six of us dined together at around table. As you know, I come fromLiverpool " he continued. " I 'fat next toEvans, and the sailor was facing me. Thewarden, sitting on the left of the fire -watcher,was opposite Clark, who sat between Brownand the soldier. Frazer was between Davisand the man from Glasgow, who sat oppositethe Home Guard. The Mancunian wasopposite. the Leeds man, who sat on theright of a fellow from Birmingham. Clarkis an airman.'

Who was the only Londoner present, andwhat does he do in the war ?

Lady Bountiful's School Treat" Lady Bountiful paid the whole cost of

our Sunday School outing," said the vicar." She hired a bus to take the children to

Winklesea, and gave them a really sumptuoustea."

" Very generous," I commented. " Didit cost her much ? '

" I couldn't say how much," the vicarreplied " All I know is that the organiserscharged so much a head-there being nofractions of a penny-and when her Lady-ship settled the bill she paid out a Bankof England note and a penny besides.Perhaps you can work it out from that," headded with a. smile.

How many children attended the schooltreat ?

Sympathy and Antipathy" Sympathy and Antipathy " is a simple

gambling game, in which the dealer detachestwo cards from the top of the pack and thepunter (of course without seeing them) betsa level stake on sympathy or antipathy --sympathy meaning that the two cards are ofthe same colour, and antipathy that there willbe one red and one black card.

It did not take my friend Cleverleigh longto realise that the odds in this game areslightly in favour of antipathy, so he sat downthe other day intending to back antipathysteadily with a level stake of a shilling eachdeal.

Coming back a few minutes later, before thepack was exhausted, I asked Cleverleigh howhe was getting on.

" Very badly," he replied. " As ill -luckwould have it, sympathy has turned up everytime."

"Dear me," I said. " Are you going tocontinue with your system ? "

" It doesn't matter whether I do or not,"answered Cleverleigh, " because the chancesare now exactly level."

How much had Cleverleigh lost?


Grinding and CrushinA MachineryThe Construction and Operation of Various Types of

Crushers Chiefly Used in the Chemical IndustryBy H. BOULTON

GENERALLY speaking, materials whenpurchased or produced for the manu-facture of such things as paints, explo-

sives, pottery -clay, glazes, and even sometypes of foodstuffs, are very coarse, andare often formed into hard lumps and masses.It is necessary to grind these materials downinto powders or a smaller crystalline size,before further refining can be done.

As grinding is usually the first processcarried out in the production of certain com-modities, it is very important, for all follow-ing treatment given to the materials isdependent on the efficiency of the first. Thedesign of machines capable of doing thiswork properly presents a number of difficul-ties not met with in any other type ofengineering design. Chief among theseproblems is the considerable difference incharacteristics of different materials. Somecan only be ground dry, so that the machinemust be fitted with dust -hoods, and allbearing surfaces have to be fitted with oil -seals and adequate casings to protect themfrOm the dust. Certain types of material canonly be ground when in liquid form, and toifiaintain this state have to be kept hot,in special hot-water or steam -jacketed mills.Others should not come in contact with anyform ,of iron, and the grinding mills con-sequently have to be lined with porcelain orsilex linings., Almost every material has itsown peculiar characteristics which call torspecial consideration. However, the follow-ing is a brief description of some of thegrinding machines used in the chemicalindustry. Attention is paid more to specifictypes rather than to the considerations whichmust be embodied in a machine for a par-ticular chemical or material. The common-est, and perhaps the one of greatest import-ance, is the ball mill, a typical example beingshown in Fig. 1.

The Ball MillThe tides' effect on pebbles. and rock on

the seashore is ultimately to reduce themdown to grains of sand. The process is, ofcourse, extremely slow, but is, nevertheless,a natural wearing or grinding action causedby the ceaseless turning over ,and smashingtogether of pieces of rock, broken off from

Vee rope drive

Electric motor

the shores by the poundingof the sea.

This principle is used bythe ball mill, the only differ-ence being that the action isvery much quicker, the desired

Scraper

degree of fineness being controlled by thelength of time which the machine is allowedto run. The material to he ground is loadedinto the mill cylinder with a quantity ofpebbles, or porcelain balls. The " grindingmedia," as these are called, are usually ofthe same material as that with which the millis lined. Thus a porcelain -lined mill requiresporcelain balls, a steel -lined mill requiringforged -steel balls, and so on. As explainedabove, the type of lining used is determinedby the material to be ground.

The mill cylinder, having been loided, isrotated mechanically at such a speed aswill cause the balls to climb part way up thecylinder wall and then fall back thrcugh anangle of about 45 degrees. Obviously, theballs when going through this " cascading "action (Fig. 2) will smash and wear the softermaterial present in the mill down to an im-palpable powder.

Probably the greatest disadvantage of thismethod of grinding is the fact that thismachine can only deal with materials inbatches, that is, it has to be stopped to allowdischarging and loading. To avoid this, thetube mill can in some cases be adopted.

Fig. 1.-Part sectional view of a large ball mill.

Fig. 3.-An edge runner

The Tube MillThis is identical in its main principle to

the machine lust described, but its method'of charging and discharging is continuous.The cylinder barrel is supported on hollowtrunnions or shafts, so that material may befed through one of these by a screw con-veyor, and discharged through the other endafter passing down the length of theThus chemicals can be ground in a continu-ous flow, and the labour necessary in charg-ing and discharging is consequently elimin-ated. It is interesting to note that thismethod of grinding, used in the ball andtube mills, is also an efficient method ofmixing. The materials are ground andmixed simultaneously.

Laboratory Ball MillThis is a machine used for grinding small

quantities of chemical compounds, and isused extensively its some laboratories. Itsprinciple is the same as that of the ballmill ; grinding is done, however in smallporcelain drums, about one foot in diameter,which are held and rotated at the correctspeed in frames fitted with suitable quick -detachable fastenings.

These machines are often designed toaccommodate up to 12 porcelain drums, andthus the machine is capable of grinding x2different materials or samples simultan-eously, one sample, of course, in each drum.When grinding is complete, the drums maybe removed, and replaced with others ; andwhilst the machine is dealing with a secondset of samples, the first lot can be tested andinspected.

We will now consider some of the othertypes of grinding machinery, which arebasically different from the ball -mill class.

The Edge Runner Mill.The edge runner mill relies for its grind-

ing action on the crushing action of a heavyroller or runner, revolving round the inside-of a large pan in which the material to beground has been loaded. The principle ismerely the obvious one of crushing thematerial between the pan bottom on whichthe roller rests and the heavy roller itself.In the type shown in Fig. 3 the pan is

March, 1944 NEWNES PRACTICAL MECHANICS 203stationary, and the whole runner assemblyis rotated by a bevel gear drive from beltpulleys. Two scrapers are fitted to thisassembly, designed to scrape the sides andpart of the pan bottom, guiding material thuscollected into the path of the runner, so thatnone of it can remain uncrushed. A furtherscraper is arranged to prevent adhesion tothe roller. The machine can discharge itscontents, whilst in motion, quite attomati-cally. A sliding door in the bottom of thepan is opened by hand, and through thisthe material is discharged, ass:.szed by thescrapers which push and guide it to theoutlet.

It will be understood that an edge runnermill of this description, would hardly be

Direction of rotation.

Fig. 2.--Diagram illustrating the cascadingaction of a ball mill.

suitable for grinding dry and dusty com-petitions, for the amount of dust generatedwould be such as to cause most unhealthyand uncomfortable conditions for personsworking near, or attending to the machine.A further disadvantage would be theappreciable amount of material lost.

Some machines intended for dry grindingare constructed as follows:

Two runners of equal diameter arearranged diametrically opposite each otherresting on the bottom of a revolving pancontaining the dry composition to beground. In the bottom of the pan a " track "of cast-st.sel plates is fitted, and it is betweenthis " track "-and the rollers that the crush-ing is done. The rollers spread the groundmaterial on to a set of perforated plates, andif it is ground sufficiently, it passes throughthese into a stationary container from which

' it is discharged. Should the material not begroun i fine enough to pass through theperforated plates, it is passed under therollers again by scrapers. A dust casing

is fitted over the pan and runners ofmachines dealing with dangerous orextremely dusty chemicals.

The Jaw CrusherAs the name suggests, this, machine con-

sists principally of two hardened steel" jaws " which are made with vee groovesrunning down their full length, lookingremarkably like long, shallow teeth. Actuallywhen the machine is working these groovesreally do have the effect of teeth. One ofthe jaws is fixed stationary, and the' other isgiven a reciprocating motion by a heavilyconstructed eccentric coupled to either one'

FRONT VIEW

ground or " disintegrated." The ball mill,of course, certainly makes use of thisprinciple of percussion, but as it is essentiallya slow speed machine the effect is verysmall and may be ignored. The disintegrator,however, running at a speed between 3,000and 5,000 revs. per minute, depends entirelyupon this force for its efficiency as a grindingmachine.

Referring to Fig. 4, it can be seen thatthe disintegrator is in appearance quitesimilar to some kinds of water turbine. The .rotor, having arms set like cutters, is installedinside a lined housing and is rotated at ahigh speed by a belt drive to the pulley

Feed

Fig. 4.-Sections of a diSintegrator.

or two flywheels, depending on the design.In this way the space between the jawsincreases and decreases as the eccentricrotates. Obviously any material presentbetween the jaws, when they close, is crushedby the great forces applied. Thus the machinevirtually devours the materials fed to it, andit is most useful for breaking stone, flint,and any other fairly brittle chemical com-pound r -;ch can be smashed by impact.The jaw crusher may also be used with suc-cess for breaking up crystalline chemicalcompounds which are apt to form into hardlumps, after becoming damn duringtransport or storage.

The DisintegratorUnlike any of the previously mentioned

machines, which depend upon a rubbing orcrushing action, the disintegrator performsits task by percussion, or, in other words,by the forcible striking and collision of highspeed rotor -arms and the material being

Discharge

SIDE VIEW

shown. The material to be ground is thenfed into the housing, and there meets theblades of the rotor, which beat it againstthe sides and top of the housing linings untilit is fine enough to pass through screens,situated above the receiving casing. Thegrinding and discharging actions are bothcontinuous.

'The foregoing is intended to cos et onlythe commonest and most important types ofgrinding and crushing machinery met within what may be broadly called the " chemicalindustry."

There are some other machines which havenot been included. Examples are the" Stone Mill " ; similar to the edge runnermill, but employing four heavy Blue -Welshor Derbyshire-Chert stones, in place ofrollers, which are " skidded " round theinside of a pan by four wooden arms, onearm to each stone. This is probably themost ancient method of grinding.

Flexible Bearings and BushingsWITH the exception 'of the special types

of machinery whose main function isof a vibratory nature, such as pertainsin shakers and certain types of crushers, thepresence of vibration and noise is unwelcome,and any expedient that will eliminate theevil is of paramount importance toengineers.

The introduction of the " Clayflex "flexible bearings and bushings has broughta solution to many of the problems arisingfrom the transmission of vibration and -thesuppression of noise in machinery ;. the" Clayflex " flexible bearings and bushings,which are manufactured by Clayflex, Ltd.,Tiddington Road, Stratford -on -Avon, con-sist essentially of a seamless tube composedof natural rubber compound which is pre -stretched between an inner and outer metaltube as shown in the sketch.

On account of the method adopted inpre -stretching the rubber compound betweenthe inner and outer metal tubes, the rubber

continually seeks to conform to its originalshape, with the result that the constant forceexerted within the rubber ensures a highcapacity bond between the rubber andmetal: the strength of this bond is suchthat it will only_ break down after the impo-sition of a considerably higher overload thanthat for which the bearing has been designed.

The load -carrying capacity of !he

Seamless Tube Ofrubber or Clayprene

Metal inner ring '

Meta/ outer ring

Section of "Clayflex'! flexible bearing.

" Clayflex " bearings and bushings varies, ofcourse, in accordance with the particularapplication for which they are required, andsince the capacity depends upon the% classof rubber compound, its length and thick-ness, in addition to the length and relativediameters of the inner and outer metal tubes,it is not practical to give a -general formulafor determining the load -carrying capacityof the full range of bearings and bushings ;an average figure, however, for the typesand sizes in the greatest demand at thepresent time is a radial load of approximately600lb. per square inch.

Where the bearings or bushings are liableto come in contact with oil or high per-centages of .ozone, a special materialmarketed under, the trade name of" Clayprene " is recommended in. place ofthe natural rubber compounds, and in orderto cater for the requirements of bearingsand bushings that must be of a self -oilingnature the " Clayflex " types can be suppliedwith the inner tube or bush made in brassor graphited bronze.


AIRCRAFT ON ACTIVE SERVICE

5.-The Handley Page HalifaxBy L. H. HAYWARD, A.R.Ae.S.

w.

ttttttttttttttttttttt4( tttttttttttt tttttttttttttttttttt14,fEt 1f 4, I

The Handley Page four-ingined, all metal, heavy

bomber.

THE Handley Page Halifax heavybomber, officially described as a four-engined, all -metal, mid wing, canti-

lever monoplane with stressed skinconstruction, is manufactured by the parent

a firm, many large " shadow " firms, and bya large number of sub -contractors. Manytypes of Halifax are now in service withBomber Command, the table below gives thegeneral leading particulars.

ConstructionThe fuselage is a light alloy, monocoque

structure with flush riveted stressed skin.The main body is divided into eight majorcompartments. The nose compartmenthouses the front gun turret, when fitted, andthe navigator who is also the bomb aimer.The second compartment is divided acrossthe middle. It houses the radio operator andhis equipment in the bottom half and thetwo pilots, who sit side by side, in the tophalf. The third.or flight engineer's compart-ment has an astral dome with a bullet-proofglass panel, enabling firing operations to bedirected by a control officer when the aircraftis attacked by enemy fighters. The first threecompartments. are all forward of the leadingedge of the aircraft wings and protectionis afforded to the crew from rearward attacksby armoul-plated bulkheads.

The crew's quarters are heated by trappinga quantity of the air which has become warmin passing over the engine cylinders and ledaway through ducts to the fuselage com-partments. Observation windows are fittedall along the sides of the fuselage. Rest

quarters fitted with bunks occupy the fifthcompartment, while the centre gun turretoccupies the sixth. Various accessories, suchas the master compass, gyro and auxiliaryammunition chutes are located in the seventhcompartment, and the rear gun turret com-pletes the fuselage assembly. An entrancedoor, with a ladder which can be retractedinto the left hand side of the fuselage whenthe machine is in flight, provides entry forthe crew. All crew stations are connectedby a walk -way extending the complete lengthof the fuselage.

WingsEach tapered, swept back wing is built up

from six main sections and seven smallerones. Twelve self-sealing fuel tanks areinstalled in the wings, and on early Halifaxaircraft -three large emergency fuel jettisonpipes were fitted in the trailing edge of eachwing. Two engines are mounted in eachwing, one at the outer end of the centresection and at the inner end of the mainspan. The ailerons are formed from lightalloy sheet and are fabric -covered. SpecialHandley Page trailing edge flaps to assisttake -off are fitted between the ailerons andfuselage. The flaps enable the huge heavily -loaded Halifax to take off from normalservice aerodromes. A dinghy for use in anemergency is stowed in the rear of the lefthand centre section. A bomb compartmentis housed in the centre' section of the wings.

UndercarriageThe massive undercarriage necessary to

support the fully -loaded bomber has a wheel

track of approximately 25ft. That meansthat one of the Miles trainer machines couldalmost be st3od between the wheel base ofthe Halifax.

A Messier type of hydraulically -operatedundercarriage unit with a large single castingforming the wheel arch is attached to theunderside of each wing at four points. Thewheels retract backwards into the enginenacelles.

CrewA crew Of seven is normally carried, com-

prising two pilots, a navigator who is alsothe bomb aimer and front gunner, a radiooperator, a flight engineer, rear gunner andmidship gunner.

Armament and Bomb LoadThe Halifax exists with several different

types of armament. Early versions carried atwo -gun nose turret, four -gun tail turret andfour beam guns. The bearti guns werereplaced by fitting a dorsal turret with twomachine-gu is. Enemy night fighters usuallyattacked from the rear and the nose turretwas eventually discarded.

To try to improve performance the dorsalturret was then removed, but most of theHalifax machines now operating have apower -operated four -gun midships -turret, afour -gun rear turret and a single hand -operated nose gun. These various modifica-tions have meant several changes in thedesign of the nose and three or four typesmay be seen flying at the present time.

Eight hydraulically -operated doors enclosethe 22ft long main bomb compdamentcapable of housing incendiary, 2501b. or5oolb. and 2,000lb. bombs. In addition, thecentre section of the wings is formed into sixextra compartments for housing 5oolb.botribs. The maximum bomb load that iscarried by a Halifax is between 5 and 6 tons..

EnginesFour Rolls-Royce Merlin XX or Merlin

XXII liquid -cooled, twelve -cylinder, 6o deg." V " type motors, operating three -bladed,constant speed, fully feathering airscrews areinstalled in the leading edge of the wings.

Span

99ft. Din.

Length

70ft. pin.

Height

22ft. Oin.

WeightMax. Load

Max.Speed

60,000 lb.

BombRange Load

MotorType

300 m.p.h. 3,000 m.Rolls-Royce

5-6 tons. Merlin

MotorPower

1,175 h.p.

March, 1944

The motors, renowned throughout the worldfor their reliability, are built to allow each ofmaintenance and accessibility and are entirelyself-contained units, including the coolantradiator and oil cooler. The Halifax can flyon two engines only.

An extremely large amount of research anddevelopm-nt work has been carried out byMessrs. Rolls-Royce so that the exhaustflames could be effectively damped out, andmany types of shields and muffs may beseen fitted over the Halifax exhaust stubs.

A great tribute to the co-operation and

NEWNES PRACTICAL MECHANICS

standardisation between Messrs. Rolls-Royceand Handley Page is the fact that one enginecan be taken out of the airframe and a newone fitted in a little over six hours.In Service

The first operational flight made byHalifax machines was during March, 1941,the targets being Kiel and Le Harve. Sincethis time the number of machines in servicewith Bomber Command has been everincreasing and to -day almost every bombingreport on Germany or the occupied countriesmentions the Halifax as having taken part.

205

The distinction of being the first four-engined British bomber on active serviceoverseas belongs to this machine. Squadronsof Halifax bombers badly dislocated theGerman communication and defence systemsduring the victorious advance of the. EighthArmy in Libya, and they were also engagedin the invasion of Italy.

One of the most outstanding four-enginedaircraft to -day, it is expected that the Halifaxwill still be " on active service " in a modifiedform in the civil air -lines now being plannedto operate at the cessation of hostilities.

Masters of Mechanics -94

Oliver EvansAmerica's Pioneer Steam Engine Inventor

NOT infrequently, Oliver Evans isdubbed " the James Watt ofAmerica," the title purporting to

embody a compliment to the inventive.achievements of this American steam -powerpioneer.

In reality, however, the cognomen is oneof more than doubtful honour. For -whilstOliver Evans was, at least, a life-longadvocate of high-pressure steam, Watt, theScotch instrument -maker, proved himselfto be wholly a bigoted, crafty and confirmedopponent of it. The honour which anofficial and unthinking history has bestowedon James Watt is aneything but justified.Consequently, to - credit an inventor inanother country with being Watt's " oppositenumber " is, however well -intended theappellation may be, hardly expressive of thetrue state of affairs.

In the industrial history of his ownnation, Oliver Evans has risen pretty muchto the status of a national hero. Indeed,some of his countrymen claim for him theorigination of the use of high-pressuresteam and, also, the construction of theworld's first locomotive. Such claims, how-ever, do not bear investigation, for Evans,brilliant. though he was, undoubtedly tookhis cue in the invention of steam enginesfrom the pioneer Englishmen who were hiscontemporaries.

Oliver Evans was born in 1755. Theplace of his birth was the then diminutivetown of Newport, Delaware, although insome historical accounts it is given asPhiladelphia. Apparently, he came of humbleyet capable parents. With his brothers, hewas imbued with innate mechanical capa-bilities, and, during his early 'teens, he wasapprenticed to a wheelwright, an occupationwhich he took to with great gusto, and inwhich he found every opportunity ofexercising his own inborn creative bent:

The "Steam Cannon!'When Evans had, arrived at manhood,

news concerning the then novel and experi-mental applications of steam `powerbeganto trickle through from England. It wassuch news which turned Evans' fancy to thesubject of constructing a machine whichwould propel itself without the aid of horses.Evans knew something about the practitalaspects of the expansive force of steam. Afavourite experiment of his (and a somewhatsensational one, in the bargain !) was to filla small iron ,cannon with water, -to plug itup tightly and then to place the water -filledcannon on the fire of his blacksmith's forge.Evans would then operate the forge bellowsuntil the small cannon exploded with someviolence. .

It was this type of experiment whichoriginally turned the mind of young Evansto the subject of steam power, and to the

effective utilisation of the expansive force ofwater vapour. He studied Newcomen's" atmospheric " engine principle, a principlein virtue of which, as the reader will, nodoubt, recollect, steam was alldwed access tothe underside of a large piston. The subse-quent condensation of the steam createda vacuum under the piston, which latter wasthen driven down by the external force ofthe atmosphere on its upper side.Newcomen's engine was not a steam pres-sure contrivance, for, in it, the only purposeof the steam was to enable an under -pistonvacuum to be created with ease and readi-ness. Like his English confreres, Evanscame to the conclusion that motive powercould only effectively be obtained from theapplication of steam by dint of making useof steam's constant and ever-presentpressure. In other words, Evans madehimself the apostle of steam pressure in hisown country, and even of high pressuresteam, for, during his subsequent career,he advocated high pressures in contra-distinction to the then almost universal low

An early American locomotive.

steam engine' pressures.His first invention of which there exists a

definite record was made when he was 22years of age. It comprised a machine formaking the metal " card " teeth which wereused in the construction of " combing "machines for wool and cotton. The inventionwas successful although Evans himselfappears to have got little out of it.

Mechanised MillingAbout the ear 1780, Evans entered into

partnership with his two brothers who werepractical flour millers. During the ensuing15 years in which he was in close contactwith his industry, he almost completelyrevolutionised its methods. Numerousinventions connected with the mechanicalaspects of milling machinery were made byOliver Evans during the period i78o-1795.He published a description of them in a

at least as -1(at-

book which he composed in 1795, and whichwas entitled The Young Miller and Miller'sGrist. Patents for milling machinery weregranted to Evans in the American States ofMaryland, Delaware and Pennsylvania in1787, and, also, by the United StatesGovernment in 1790 and in 18o8.

Evans' invention simply mechanised theprocess of flour milling which, previously,had been very much -of a hand operated job.He practically eliminated all manual labourfrom the milling process. From the timethe crude grain entered Evans' mills untilit was collected in clean sacks, the materialwas untouched by hand. Evans not onlyspeeded up the milling process ; he alsocheapened it and enabled a cleaner, and amuch -improved product to be obtained.

It was during the course of these millinginterests and inventions that Oliver Evansdeveloped his early ideas on the subject ofsteam poiver. Steam power, to him, was animportant achievement, for not only wouldit enable him to drive his flour mills faster,more cheaply and with greater economy, but,

also, it would be themeans' of allowinghim to devise otherobjects of its em-ployment, particu-larly the ' self-propelling carriagewhich Evans hadpondered over in hisactive. imaginationever since hisearliest wheelwrightdays.

Evans was anearnest man, andhad the courage ofhis convictions, somuch so that, in duecourse, his planscame to be re6aided

un feasible.

High-pressure SteamIn general, Evans planned a steam engine

operating at high steam pressure. Many ofhis present-day countrymen state that OliverEvans originated the employment of high-pressure steam, and they point to, the factthat, in 1787 (and, also, in 1795) he "sentplans of his high-pressure steam engine overto England.

Now, in England, the Cornishman,Richard Trevithick, is usually considered tobe the originator of the high-pressure engine,which he brought out and developed in theface of the bitterest opposition on the partof James Watt and his party. The Americanssay that Trevithick had sight of EVans'plans, and that the former took his ideasfrom the latter. It is impossible with anydegree of certainty to deny or to assert such

206

a happening, although all the available andaccredited evidence favours the British con-ttntion that Richard Trevithick, theCornishman, was the true originator of thehigh-pressure steam engine.

High-pressure steam engines were con-structed independently by Evans and byTrevithick about the year 1800. Bothinventors subsequently applied their enginesto propel road carriages, but, in this con-nection, it is quite certain that to RichardTrevithick belongs the honour of havingbeen the first man to make practical use ofsteam power on a railway.

Locomotive ProjectsAlthough Oliver Evans did not succeed in

constructing a serviceable locomotive enginebefore the dawn of the nineteenth century,his connection with the subject of locomotivetrains goes back to 1787, for in that yearhe . actually obtained from the State ofMaryland an exclusive right' to construct asteam train " that would run on a level withthe swiftest horse." Later, he was grantedthe right (without opposition) to providesteam carriages that would " run at the rateof 15 miles an hour on good, levelrailways."

Perhaps it was the ineradicable streak ofthe visionary in his character which wasresponsible for Evans dying a comparativelypoor man. He seemed to lack the abilityto prosecute his designs in concrete form,as one might put it, to the bitter end. Forall that Evans possessed tremendousenthusiasm, which was of an infective'nature.It was Evans, without any doubt, who laidthe trail of the " steam engine fever " .inthe United States of America at theconclusion of the eighteenth and thebeginning of the nineteenth centuries.

There is little doubt that Evans experi-enced opposition to his locomotive schemes.Such opposition was only made the strongerby his not having a locomotive ready to placeon a railway or on the road. It is said thatan American engineer who was acquaintedwith Evans' prOject for a railway wrote asemi-official report in which he stated, thatit would be materially impossible to run avehicle on four wheels by the means ofsteam!

Stone -sawing MachineBy way, perhaps, of a change from his

steam locomotive designs, Evans, in 1803, -constructed a stone -sawing machine whichwas operated by a high-pressure stationarysteam engine. The engine, so the recordstates, drove " 12 saws in heavy frames,sawing at the rate of iooft. of marble in 12hours."

In his steam engines, Evans used acylindrical boiler having a cylindrical flueinside it, the fire being placed within the

-flue. Such a construction formed the originof the present-day well-known Cornishboiler. Richard Trevithick used a similartype of boiler, and it seems likely that, boththese inventors designed their boilersentirely independently of each other.

The " Puffing Amphibian "In 1804, the year following his successful

" stone -sawing machine," Evans determinedto buill for himself a steamboat. Previously,in 18or, he had made some attempts at thesame project, but they had never come toanything. In 1804, however, the steamboatwas completed. In tattler to get it from hisworkshop to the river, Evans had to providethe vessel with four under -wheels. It was acurious contraption, and its inventor andconstructor saddled it with a still morecurious name. Evans called his somewhatfantastical boat -car the Eritctor Amphibolisor the " Puffing Amphibian."

NEWNES PRACTICAL MECHANICS . March, 1944

The available accounts of Evans'"Puffing Amphibian" vary. Some say thatthe boat -car was successfully driven alongthe streets of Philadelphia to the river andthen equally successfully launched therein.Other accounts, and probably the morereliable ones, state that before the vessel wasfinally completed, it underwent totaldestruction as the result of a disastrous firewhich occurred in Evans' workshop. Theincident is supposed to have played so muchon the mind and the health of the inventorthat, after this disaster, he relinquished thegreater. number of his, more " advancedprojects of which he had formerly been sofond.

It is certain that from about this date hesank gradually into an obscurity from whichhe never again arose. Itis true that, as one of hislast public acts, he planneda railway between NewYork and Philadelphia, butnothing ever came of thisproject. Unfortunately,Evans, at this period of hislife, had neither the abilitynor the means to carry outsuch a formidable andrevolutionary plan. Hereturned, therefore, to hisflour milling, an occupa-tion from which he even-tually retired when en-feebled by ill -health.

Evans died in New Yorkon April 16th, 1819, hisdeath being very littlenoticed at the time.

For a century or more,Oliver Evans and his pion-eering work have beenentirely forgotten by hisposterity. It is only within comparativelyrecent times that his memory has beenresurrected. It would not be true to statethat Oliver Evans was in any sense a great

inventor. Furthermore, he lacked the abilityto concentrate on a job and to see it throughto its ultimate satisfactory culmination.

Yet in spite of all his constitutional faultsand defects, Oliver Evans functions as alandmark in American industrial, engineer-ing and economic life, and, to a certain extentin the wider narrative of the world'sengineering activity.

Evans found the way of the pioneer andthe mai with a creative vision to be a hardone. Let us therefore take advantage ofthe histor,cal perspective in which we arenow placed, and, in consequence, endeavourto realise the precise impact which Evans'inventive energies made upon the course ofsteam engine development. That it was,

The trial of Trevithick's first locomotive.print.)

on the whole, a favourable one and, in somerespects, even a memorable and distinctiveone is the verdict which history has nowpronounced.

(From a contemporary

Solutions to Probes and Problems(See

Four Men from the ProvincesMr. Bristol.Mr. Dover lives in Cambridge, Mr.

Cambridge in York, and Mr. York in Dover.

Down Our StreetMr. Black lives at Whitefield.The complete solution is as follows:Name of House Colour

Greystones brownBlackfriars blackBrownleaves whiteWhitefield grey

, OccupantWhiteGrayBrownBlack

Phoney 'PhonesPOPesgrove 0281.

Energy on the Escalator54 seconds.

Services Dinner PartyClark, the airman, must have been the

Londoner.Numbering the seats clockwise, and putting

Adams at No. a, the party was arranged asunder:No. Name Home town Service

r Adams Liverpool Home Guard2 Evans Manchester Soldier3 Clark London Airman4 Brown Glasgow Sailor5 Frazer Leeds Fire -watcher6 Davis . Birmingham WardenA second solution, with a different set of

page 201)diners, is possible according to the terms ofthe puzzle. In that arrangement, however,Adams would be the soldier. Since he

." stroked his beard " and beards are notpermitted in the Army, this second solutionmust be rejected.

Lady Bountiful's School TreatThere were 49 children, and the outing

cost 4s. id. per head.Lady Bountiful could not have paid

los. rd., since that would have meant iichildren at rid. per head, and one couldnot have a bus ride and a " sumptuous tea "for as little as IId. 241 pence (kt os. ad.)and 1,2o1 pence (£5 os. ad.) have no factors,whereas sums over L20 would require toomany children for a bus -load or too higha cost for the outing.

She must therefore have spent to os. Id.(2,401 pence). She would not have hireda bus for as few as seven children, and onebus could not have accommodated 343 ofthem. Therefore there must have been 49children.

Sympathy and Antipathyas. It can be proved that for the chances

to be even, the number of cards left must bea Square number, and (since sympathy hasturned up every time) an even square.

Experiment shows that the only possiblenumber of cards remaining is 16, so that36 cards have gone and there have been 18deals. Thus Cleverleigh must have lost t8s.

March, 1944

Relics ofNEWNES PRACTICAL MECHANICS 207

"LonA John Silveri,Many Interesting Additions to be Seen

IUNDERSTAND that considerableinterest was taken in the article Icontributed to the January, 1939, issue

of this journal on " Long John Silver's "collection of ships' relics at " The LookOut " on the Waterfront at Gravesend.During last summer this collection was opento the public for the first time, for the benefitof the Merchant Navy Comforts Service, anda short while later I again had the pleasureof visiting this " Valhalla -by -the -Thames,"as it is sometimes called. I found that sincemy last visit there had been many importantadditions to this unique collection. Thereare now over 600 relics and souvenirs-anamazingly large number for a private collec-tion-and the realisation that each one haseither a romantic history attached to it, oris the only example of its kind in existence,must make a lover of the sea and ships feel

Fig. r.-(right). " Long John Silver"-fromthe painting in oils by his artist friend.

Fig. 2.-The Forecastle-or " Model Room."5.

almost reverent, and most certainly awe -inspired, upon entering. I welcome theopportunity of being able to tell you aboutsome of the new figureheads and models,and about some of the older ones I wasnot able to mention in my last article.

The " Model Room"I dealt mainly with the bridge last time ;

this time I shall devote myself to theForecastle and Valhalla. The Forecastle isthe " Model Room." Nearly all the modelshave been made by men of the sea, quiteoften during the long and tedious voyagesof the " square rigger ", days, and one canfeel the love and care that went into theirMaking-nothing impersonal or " land-lubberish " about these models. In my firsttiff of the ForeCastle (Fig. 2), the modelkinder the Eagle is of an old Blackwall frigatet -the Renown-modelled by her bos'n.Next to her is the Loch Torridon' the sailsof which are made entirely of tobacco tins.A rather interesting " relic " can be seen

at "The Look Out," Gravesend

By W. J. BASSETT-LOWKE, M.I.Loco.E.

on the extreme right of this picture. It isa carved Viking drinking horn which Capt.Silver found in .an old farmhouse in Icelandabout 4o years ago. The mountings are,of course, modern. Next to the hornis a particularly fine model of ForwoodBros.' s.s. Orotava;

An historically interesting model is setbetween the two figureheads to the left ofFig. 3-it is of the last English -owned squarerigger (four -mast barque), the Garthpool. Inthe centre of this same photograph-immedi-ately under the figurehead Sophie Kirk-isa model of the Gull. It was made by hership's carpenter, and all the sails are of wood.I was not surprised to learn from " theCap'n " that this is considered to be oneof the best examples of carving in any model.Another model is of the oldest craft in com-mission-the Ellen. She is at least 540 yearsold.

The " Queen Mary "In the third photograph of the Forecastle

(Fig. 4) will be seen a " modern " touch-amodel of the Queen Mary, made by one ofher crew. She seems almost to be trespass-ing in tlit* place, where time has beenarrested and " the past " is still " thepresent . . . where the " good old days "still hold sway. Above her, on the wall, aretwo builders' half -models. " Valhalla " is thereal " home" for " Long John's " figure-heads, but his collection is now so large(it is the largest private collection of mer-chant ships' figureheads in existence) thatsome have, of necessity, had to " overflow "into the Model Room. To save confusionI will deal with these before entering "Valhalla. On the extreme left of Fig. 3 isa fine figurehead of the Sovereign, an oldbrig. The right arm is detachable, and,upon inquiring why, I was told they usedto " unship 'em at sea "! A chance photo-graph revealed the identity of the nextfigurehead as being from the Aberdeen Lines.s. Thermopylae. For many years it hadbeen one of the few " unknowns " in Capt.Silver's collection. Next, with arm out-stretched, is Zenobia, an old Salcombe

Fig. 3.-The Forecastle again-note " Elizabeth Fry" in the corner.

-4


Fig. 4.-The view of the Forecastleshowing the " Queen Mary."

" fruiter "-one of the last of along line of these famous craft.iTo many, history is "dull and

uninteresting," but everyone re-members the little human storieswhich every so often creep intothe history books. One of them isabout Elizabeth Fryrememberhow she used to hold services onthe convict ships before they sailedwith transportation prisoners ?What more fitting than that sheShould " adorn " a ship's bows ?'And there she is in the corner,with her prayer book in her hand.

' Although , figures of humanbeings were by far the most popu-lar as figureheads, birds andanimals were used, and a superbexample is the 4agle on theextreme right of this picture, fromthe full-rigged ship of that name(1856). Although the days whenshe " proudly sailed the seas " arelong since gone, this ship is stilldoing useful service-as a coal hulkin Gibraltar Bay.

The dog over the door in Fig. 4has a very definite claim to" fame." He is from the quartergalleries of the Sirius-the firstBritish steamer to cross the Atlanticunder her own steam. You maybe interested to know that thefigurehead of this ship can be seenin the Hull Municipal Museum.

The two most recently acquired figure-heads have been " coveted " by " LongJohn " since he was eight years old-trulya perfect example of "patience rewarded "!One of them can be seen to the left ofthe dog, and the bottom of the other isjust visible to the right of Fig. 2. Thislatter is of a man of the early nineteenthcentury-possibly from the Lord Beacons-field-but there is, unfortunately, no traceof the other. Both ships were sunk offRamsgate-one on the Broadstairs KnollBanks and the other on the Goodwins-and the figureheads stood in the sheds inBeeching Moses' shipyard on the west sideof Ramsgate Harbour for many years (itwas here that Capt. Silver used to gaze atand long fir them). When the yard was

Fig. 5.-(above)" Valhalla."Fig. 6.-(right) The seascape from the

bridge with stuffed gull on davit.

dismantled they were removedto a shipwright's store, and itwas from here, after long nego-tiations, that they at last " cameinto their own " and enteredthe sanctuary of " The LookOut," to be cared for by " LongJohn."

" Valhalla "And now " Valhalla "-full of

so many memories of " gallantmerchantmen " proudly battlingagainst the whims and fanciesof that great force, the ever-changing but unchanged sea "-still untamed even to -day,despite the great strides that

are being made in land, sea and air power.The very beautiful piece of carving at thetop to the left of the picture is thoughtto be from the Helene, one of the Bordes" White Ships." On her right is OldGoody, a 174 tons brigantine built in 1865.William Wilberforce (1868)-famous as theemancipator of slaves-comes next, thenMaud, from a 1,108 tons barque built in1878, which became an' isolation hulk atPlymouth before being broken up.Cleopatra will easily be recognised. Nextto her, with scroll in hand, is Havelock,from an 1859 barque. The Bride, from a292 tons iron screw steamer built in 1863,is, unfortunately, almost hidden by the ship'sbell in the foreground, but her " history "is an interesting one, as she was namedafter Queen Alexandra. who came toEngland that year as the bride of KingEdward ' VII. Tradition has it that sheactually landed on a pier facing the lawnsoutside " The Look Out." . Last of all isAbraham Lincoln, from a 688 tons wooden

barque, built in 1865.But the most precious of all Capt.

Silver's wonderful collection offigureheads, and worthy of specialmention, is the Golden Cherubs(1663), which overhangs Cleopatraand Havelock. This is the. oldestand rarest figurehead known toexist. It is reputed to have been

' carved by Grinling Gibbons, andonce adorned the bows of JohnJacobs' frigate. Jacobs was the mostAtorious smuggler and plunderer ofhis day, and his portrait in oils isone of the most interesting, to anoutsider, of " Long John's collec-tion of photographs and pictures,most of which are more of personalinterest to their owner than famous.Apparently the feature of this figure-head which makes it so rare is thatit " fiddlevariety. From -the little informationI have been able to give you hereyou will not be surprised to learnthat the' Golden Cherubs has a longand romantic history-one day Ihope to make this figurehead thesubject of another article.

(Continued on page 2 to)


Letters f fromA CYCLE LIGHTING UNIT

SIR The blackout " hours usually renewthe cyclists' headache over the question

of lamps and batteries.The following particulars are of a scheme,

which, during the " blitz," I found mostsatisfactory-one Ever -Ready 2 -cell battery(used 20 minutes nightly) lasting the wholeof last winter !

The basis of the idea is to run one's front

Top of Old Torch

right Fit on CircularWood Block,

Bulb Holder Tight Fitin Hole Drilled inCentre of Block

Details

Readersfor the battery to rattle about (one cause oftheir early deterioration).

This box has a sliding lid at the rear orbottom end and a radio socket at the other,which makes contact with the top strip onthe battery. The side strip on the batteryfaces downwards and contacts a bolt whichsecures the rear lamp beneath the batterybox, which is finally secured beneath thecarrier by means of two screws.

Fixing ScrewS/ide Lid

Old Circular Rubber Heel........

Lamp Bracket

of a front

Contact Bolt SecuresRes,L Lamp to Box

and rear cycle lighting arrangement.

and real lamps in series from the samebattery, thereby doubling its life and re-ducing the power of each lamp.

The screw -type switch on an ordinaryheadlamp is removed, and an ordinaryradio socket (insulated from the lamp casing)is inserted. The circuit is completed byinserting a plug connected to the centrecontact on the hack lamp via a length offlex (see sketch below). Earth return viathe frame is unsatisfactory, and can beimproved by a direct soldered connectionbetween the lamp cases. Ordinary lampssuffer from the defect of rust and dirtinterrupting the electrical circuit throughthe various parts of the casing.

ConstructionIn the scheme illustrated above the top

of an old focusing -type torch was wedgedon to a circular block of wood through whicha hole had been drilled to accommodate thebulb -holder, the bottom contact of whichhad been replaced by a long bolt, insulatedall roun.1

This bolt passes through a discardedrubber heel, and secures the lamp holder tothe cycle lamp -bracket by means of aninsulated nut.

The wood block with torch top attachedis slid over the bulb holder, and secured bya screw and washer through the -back of thelamp. bracket. The wooden battery box wasbuilt round an ordinary 2 -cell battery toensure a good fit and obviate any tendency

-Replace Switchwith insulatedRadio Socket

Method of converting an ordinary lighting set.

The centre contact of the rear lamp bulbis connected to the case of the front lampbulb holder, the centre contact of the latterbeing connected via a plug to the socketin the battery box.

Details will depend on materials to hand,but providing the parts are solidly con-structed, and proper attention given toinsulation, no difficulty should arise.

This latter method is thoroughly recom-mended as the battery has far better pro-tection from the rain and damp, especjallyif the carrier is of the " solid " top variety,.and the mudguard adequate.

S. H. THOMAS (London, S.W.t6).

ELECTRIC CLOCK CONVERSIONSIR,-Wishing to dispense with batteries,

I decided to experiment with someparts from an old radio set which had aWestinghouse rectification:

As the clock was functioning quite satis-factorily on batteries, I did not wish to makeany alteration to the electrical system otherthan the method of supply, therefore trans-forming the current alone would no suf-fice. I then tried a portion of t -bar of theWestinghouse rectifier, fitting a brass clip toslide along the copper oxide rod, which Ifound served two purposes: (a) Rectifica-tion, (2) Voltage reduction. I then put thetwo 4v. windings on transformer in series,and adjusted the clip on the rectifier togive me the voltage that the clock wasusing on battery, namely 41, and found thatby using in addition the mains condenser

across the circuit, that the clockwould function quite satisfactorily.Another advantage of not inter-fering with the battery operation isthat a relay can be arranged fromC.T. on transformer to work on2v. A.C, and operate a battery inthe case, of mains breakdown.

My clock has been working forabout sir months now, as describedabove, and with a 151b. pendulumweight I get 52 swings per impulseon mains, as against 35 on batteryoperation.

The unit here described hasthe advantage of simplicity andreliability, and constructors of the

"P.M." Battery Master Clock with A.C.mains at their disposal will find it worth thetrouble of assembly.

The parts required, if not already at hand,are usually obtained from the local junkshop, an old radio set with " Westinghouse "rectification will supply all the parts thatare not easily made, and the coil for therelay .(if fitted) can be taken from anordinary domestic bell.

Whet/. the components Ithve been col-lected, it will be necessary to arrange themto find the size of baseboard required thewriter found Sin. by 6in. would be sufficientand thus enabled the unit to be fitted toa small cabinet to form the base of the clock;although this is not essential, it is well toremember that mains voltage enters theunit and therefore precaution should beexercised.

Another point to bear in mind is that itis not the voltage that works the clock ; thecurrent or amperage supplied by the unitwill be found to exceed that of a batteryand it is on this fact that the success ofthe unit depends.

You will observe from the illustration(Fig. a) that only one' bar of the rectifieris used, the reason being that the Westing -

Plan

Elevation_

Grass Clip C

,,X ;a.Grass Bracket,

x

Fig. a. Plan and elevation f# the A.C. mainsunit, and details of clip and brackets.

house rectifier in a radio set is designed towork on high voltage and we require it tooperate on a low or 'transformed current,and the clip C is fitted to enable adjustmenttq be made.

' It is advisable to raise the rectifier abovethe rest of the unit, as shown, by bracketsA and B as a certain amount of heat willbe dissipated, and a few holes bored in theback of the cabinet just behind the rectifierwill ensure adequate ventilation.

Now tut ning to the transformer, first seethat input on mains side corresponds to thesupply in use ; a length of 5 amp. lightingflex will he quite sufficient to carry the load,and this should be kept as short as possibleand connected to its own plug, as obviouslyit will be switched on all the time the clockis in use.


Looking at the low voltage side of thetransformer it will be seen that there are atleast two sets of terminals (or tappings)generally marked 4 volts, and also one inthe centre marked C.T. (centre tap). Thiswill be referred to later. Each of thesetappings if connected in series will increasethe voltage by the amount shown on theterminals, so therefore connect the insideof the first pair to the outside of the second.and so on, which will leave the outsideterminals vacant to carry the wires, 2 and 4,to the rectifier and clock, the condenserbeing a safety measure, is put across thecircuit-that is each wire is connected toone side of the condenser.

rap B.4 erda

4 54 C/earance

Soft iron Coil Bracket 0

Indent Rivet

"Armature of Soft Iron

X a"Phos. Bronze Spring

010 X

Tap 4 8.A.

setS,br Pole H

Fig. 2.-The complete relay and details ofthe parts.

-4

The wire marked (3) taken from clip Cand wire 5 from the condenser form thetwo leads to take the place of the batteryin use, the only other wire is taken fromclip C to the opposite side of the condenser.

When the wiring has been completed andchecked the rectifier can be adjusted bysliding along clip C, which should be movedto the right as far as good performanceallows, the further along the better therectification, and the lower the voltage, butit will be found that the number of swingsof the pendulum per impulse has beensubstantially inproved for the correspondingbattery voltage.

The unit to drive the clock is now com-plete whilst the mains are working, but bythe use of a simple relay and standbybattery it is quite easy to guard against theseoccasional annoyances.

This is where the two outer terminalson the transformer come in ; a wire fromthose, as indicated in the top sketch (Fig. t)will supply 2 volts A.C., which will be foundquite sufficient to energise a relay which, inthe event of mains breakdown, switches onthe battery.

The illustration (Fig. 2) explains itself,but perhaps a few remarks on running abell coil on A.C. will be helpful.

In order to reduce hum caused by theuse of alternating current, it is wise to slotthe pole piece, as shown at H ; an ordinaryhacksaw cut will suffice.

A further point to be observed is to seethat when armature and pole piece are incontact, they are well " bedded," and toassist in this it is advisable to arrange thatthe contact spring is at right angles to thepole -piece when in contact. Bend slightlyback and screw the adjusting contact on Gto suit, and a small indent made with acentre punch will assist in battery contact,

and a battery of the same power as formerlyused is, of course, necessary.

The connections to the switch, or relay,are : G to battery, E to clock and, of course,the other wire from battery directly to clock,

Finally, see that the transformer clampingscrews are tight ; fix a strip of felt or similarmaterial under the baseboard, and thereshould be no perceptible hum.

F. W. KEYWOOD (Leicester).

SPACE ROCKETSSIR,-I note in the January issue that a

reader has been asking about ipacerockets, and feel that I may be able to helpa little. Some time ago, whilst studyingspecial fuels, I read a book by the BritishInterplanetary Society, and whilst I cannotnow remember the name of the book, thefollowing facts may be of interest to yourcorrespondent, They are quoted frommemory, but are, I think, reasonablyaccurate:

(I) In the German " Mirak " rockets,using first petrol and liquid oxygen, andlater alcohol and liquid oxygen, the combus-tion chamber was of copper, but burnt out,then given a ceramic lining, but still burntout, and, finally, water .was added to thealcohol to reduce the temperature in thechamber until the fuel amounted to a lightbeer for alcohol content. The fuel was fedby carbon dioxide pressure behind it, and theoxygen by evaporation. (The oxygen con-tainer had to be fitted with a safety valve.)

(2) To leave the earth's gravitational fielda speed of 60o miles per second was calcu-lated to be necessary.

(3) Nothing was stated as to method Mignition, but it will obviously be, necessaryto apply considerable heat to such a fuelas the above to ignite it.

(4) Solid fuel rockets were stigmatised asbeing very much more dangerous thanliquid, being responsible for most of thedeaths, so far, Oberth, Opel, etc.

(5) Stress was laid in the book on thegreat cost of experimenting, together withthe, up to then, relatively small resultsobtained.

J. SCANLON (Leeds).

SIR,-I was extremely interested in Mr.Boggio's query on rockets, in the

January issue of PRACTICAL. MECHANICS, andin your answers.

Wilt regard to the British InterplanetarySociety, this is in hibernation for the dura-tic of the war, but the furthering of thescience of astronautics is being carried onby the Manchester Astronautical Associationand the Astronautical Development Society.These two societies are working in closeco-operation, and if any of your readers areinterested, further information may beobtained from either Mr. K. W. Gatland,

Southcote Avenue, Tolworth, Surbiton,Surrey (A.D.S.), or Mr. E. Burgess, 7,Hillview Road, Denton, Manchester(M.A.A.).

The only two books in English on thesubject that are likeIS, to be obtainable atthe present are Rockets Through Space, byP. E. Cleator, published in 1936 by G. Allenand Unwin, Ltd., at 7s. 6d., and Stratosphereand Rocket Flight, by C. G. Philp,published` by Sir Isaac Pitman and Sons in1935 at 3s. 6d.

J. HUMPHRIES (Farnborough).

CYCLE CRANK ATTACHMENTQIR,-Noticing H. H. Valentine's article,

" Cycle Crank Attachment," in theOctober, 1943, issue, I thought perhaps hewould be interested in how I overcame thesame difficulty with a difference. I have astraight leg, the only movement beingobtained from the ankle.

I may say that at week -ends I havecohered as much as 6o miles in a day. Myattachment has two distinct advantages :

(1) Quickly and easily detachable (byremc 'ing cotter pin).

(2) No friction, and it is also adaptable toright or left foot.

M.S. CbIlerturned tosuit ban races

weideri tocrank.

2 Magnetoball races

Pedal

The materials required are : two cranks,two magneto ballraces, one pedal spindle andone piece of mild steel for making the ball -race housing. The complete assembly isshown in the accompanying sketch.

E. F. HACKSHAW (Twyford).

BottomBreCket,

Crank weldedalter beingshortened.

peal spindleturned to saltinside diameterof ball races.

General arrange-ment of E. F.Hackshaw's cyclecrank attachment.

RELICS OF "LONG JOHN SILVER"(Continued from page 208.)

A Realistic SettingOn this last visit I took a photograph

" looking seawards from a portion of thebridge," and I think you will agree that,with the seagull perched on the top of thedavit, the effect is quite amazingly realistic.A lot of the credit for this " illusion " mustgo to the artist friend of " Long John " whopainted the surrounding seascape (he wasalso, incidentally, the modeller of the QueenMary in the Forecastle). This artist friendhas painted an excellent portrait in colourof " Long John " himself, and I am happyto be able to reproduce a photograph I tookof this picture. If, therefore, any readersare sufficiently interested to want to visit thisfascinating " seaman's paradise," they willeasily recognise the owner when he welcomesthem at the foot of the " Gangway "! Oneword of warning, however. " Long John "is a busy man, and can only visit his water-front residence at odd times in the springand summer. A visit must, therefore, bemade by appointment, and he has especiallyasked me to say, " Please don't make thisjourney to Gravesend, either direct or viaTilbury (which includes a ferry across theThames), unless you are genuinely interestedin the romance and history of ships throughthe ages."

NEWNES ENGINEER'SVEST-POCKET BOOKBy F. J. CAMM 10/6 or by post 11/.

Obtainable from all booksellers, or by post fromGeorge Newnes, Ltd. (Book Dept.), Tower House,

Southampton Street, London, W.C.2.


QUERIES a/44

ENQUIRIESA stamped addressed enveldpe, three pennystamps, and.the query coupon from the currentissue, which appears on page iii of cover, must beenclosed with every letter containing a query.Every query and drawing which Is sent mustbear the name and address of the reader.Send your queries to the Editor, PRACTICALMECHANICS, Geo. Newnes, Ltd., Tower House,

Southampton Street, Strand, London,

Heating Small AquariumsHAVING taken an interest in tropical fish

breeding I would be pleased to know ofMethods- of heating and airing aquariums.-H. Collis (Beckenham).TN order to heat a tropical or sub -tropical aquariumL you require an immersion heater, whrth comprisesmerely a specially -wound electric element placed inan ,insulative case. Such articles can be obtained fromany dealer in aquaria requisites, as, for example,Mr. B. T. Child, 113-r2r, Pentonville Road, N.I,Messrs. L. Cura & Sons, Bath Court, Warner Street,Mount Pleasant, E.C.r, or The Waterloo GoldfisheryCo., 47, Great Guildford Street, Borough, S.E.I.The same firms will also be able to supply variousdevices for berating aquaria. These consist usually ofsmall motor -pumps which project a miniature jet of

water, fountain -wise, above the surfaZe of the waterin the aquarium. Quite a good and a simple devicefor " airing " an aquarium consists merely of a narrowglass tube positioned atiout a foot above the watersurface in the aquarium and connected to the mainwater supply. On allowing a slow stream of water toflow through the tube it breaks up into a series of drops.which fall into the water, each drop carrying a little airwith it. This system, however, necessitates the provisionof an overflow to the aquarium and some type ofeffective screen to prevent the inmates of the aquariumfrom disappearing via the said overflow ! If, however,you approach any of the above -mentioned firms theywill be very ready to give you practical advice concern-ing your needs.

Making Ventilators for Model LaunchT WISH to make some small ventilators to fit

on to a model motor launch. I have heardthat these could be made by copper depositingon lead castings, afterwards running the leadout.

I shall be glad if you can give me any informa-tion on this subject.-A. S. Boyes (Birmingham).YOU can deposit a substantial shell of metallic

copper on a lead model by making the latterthe negative electrode of the following plating bath,the positive electrode comprising a rod or a strip ofcopper, or, better still, a cylinder of copper sheet,which is curved around the negative electrode.

Copper sulphate, 28 ozs. ; sulphuric acid (conc.),4 ozs. ; water, t gallon. Operate the bath at atemperature of 70 deg. to 75 deg. F. Voltage,preferably from an accumulator.

After a shell of copper has been built up on the leadmodel the connecting wire can be pulled away. Themodel is then heated, and the lead allowed to run outthrough the hole made by the removal of the wire.

As an alternative method, you can cast your modelin wax, and then dust the wax over with fine graphitepowder. The graphited model can then be plated inthe above manner, and the wax finally removed bymelting.

Chemicals from Sea -waterT DESIRE some information regarding the

" Isolation of New Chemicals from Sea -water "-new in the sense that they are not usuallyobtained from this source, e.g., gold, bromine,magnesium, etc. Could you please tell me, ofany books or references where I might obtainsome information on the subject ?-A. W. Cleland(Pumpherston).THERE are no books of reference relating to theA obtaining of chemical substances from sea -water,important though this interesting subject undoubtedlyis. The Germans, particularly Dr. Haber, tried hardto obtain gold from sea -water, but they gave it up asan impracticable proposition. It has also been proposedto obtain copper from sea -water, but this project, too,is apparently- impracticable.

The only successful sea -water process is that whichis being worked on the eastern coast of America forthe recovery of bromine from the sea. Essentially thisconsists in the treatment of sea -water with chlorine,which liberates the free bromine. Practical details arenot available, being maintained- more or less secret.By electrolytical methods it is considered practicallypossible to extract magnesium from sea -water, and ofcourse it would be possible to obtain metallic sodiumfrom this source, merely by evaporating the water andelectrolysing the fused salt.

We are afraid that if you want any more detailedinformation on this subject, particularly on the subjectof bromine extraction, you will have to write to the

American Bureau of Standards, Chemical Division,Washington, U.S.A., band inquire whether they haveany literature available. Some papers on sea -waterchemicals were, about to years ago, published in oneor two of the German scientific journals, but these arenow quite unavailable.

If you -consult a good modern textbook on inorganicchemistry, such as J. W. Mellor's " CorstprehensiveInorganic Chemistry," you will come across severalreferences to the presence of various substances insea -water and the possibilities of their extraction, butyou are only likely to find the above many -volumemonumental work on the shelves of a large or importanttechnical reference library.

Chemistry Course : Silver-platingT WOULD be pleased if you will kindly answer

the following queries :(a) I wish to take a dearer. So chemistry, and I

am studying a course on Matric. chemistry.Can you suggest what books to follow on fromthe course and where could I obtain them ?

(2) I have one or two small articles that I Wishto silverplate in my spare time ; can you tellme how this is done, and what chemicals willbe required ?

(3) I would also like to know a firm where canobtain leather work tools and leather.-K.Hargreaves (Rochdale).

YOU do not state your age, but we assume thatI you are still at school and that you have not yetpassed Matriculation. Before you can study for a

degree- or a professional diploma in chemistry you musthave passed Matriculation, or an examination whichwill exempt therefrom. For particulars of all suchcourses of study you would, we think; be best advisedto apply to your local teclmical institute, or, alternatively,to one of the day " c*tinuation schools " in yourdistrict.

Having obtained your Matriculation or exemptingexamination, it would be quite impossible for you toprepare for a degree or a diploma in' chemistry merelyby studying textbooks. Much practical work isnecessary, and this extends over as much as six years.For this and other reasons it would be useless for useven to attempt to give you a list of books which youmight require for your future course of studies. Thatmatter can only be decided on when the particularcourse of study commences.

Your best menediate courses of action are : (a)Consult your local technical school. (b) Consult thePrincipal of the Manchester (or Salford) College ofTechnology. (c) Write to the Registrar, Royal Instituteof Chemistry, 30, Russell. Square, London, W.C.r,requesting particulars of the " Studentship " of the`Royal Institute, and also for a copy of a publicationentitled " The Profession of Chemistry," which willhelp you ' enormously in your final choice of yourfuture career.

(2) The best silver-plating is done with the use of asilver cyanide bath, which is excessively poisonous.You can, if you wish, obtain silver-plating salt readymade up from Messrs. S. Canning and Co., Electro-platers, Birmingham, but you will probably find thefollowing formula suitable for small articles, since itgives a silver deposit without electrical means : Silvernitrate, t x parts ; sodium hyposulphite, 20 parts;sal ammoniac, 12 parts ; whitening, 20 parts ; distilledwater, 200 parts.

The articles are cleaned well and immersed in thissolution for a few minutes. Silver nitrate can beobtained from Messrs. J. W. Towers, Chapel Street,Salford.

(3) Leather work tools can be obtained from the" Leatlierwork Shop," Bridge Street, Deansgate,Manchester, or from Messrs. G. W. Russell, Hitchin,Herts.

Copper -platingIWISH to make a small number of miniature

boats by copper -plating. I can manage thepattern, and the making of a moulding box inplaster of Paris, but what I want to know iswhat material should be used for the actualmould, and how to proceed to plate it ?-D.Halliday (Halifax).S far as we interpret your inquiry, you wish to makeL./ miniature ship models comprising a hollow shellof copper, the latter being formed by electro-deposition.In this instance the mode of procedure is as follows.

Using a plaster mould, cast the model of the shipin wax, preferably in a hard wax. Then remove thewar from the mould and secure a copper wire to themoulded wax. Using a camel's-hair brush, dust thewill model over with fide graphite powder, makingquite sure that the graphite adheres to every part ofthe wax model and also that the graphite makes effectiveelectrical cohtact with the copper wire.

Now immerse the graphited wax in the followingplating bath- so that it forms the negative electrode(gathode), the positive 'electrode (anode) being a rodor strip of copper : Copper sulphate, 28 ozs. ; conc.sulphuric acid, 4 ozs.; water, I gallon.

Operate the bath at a temperature of 70 chg. to75 deg. F. Use a current voltage of t=r.s, preferablyfrom an accumulator.

After about half an hour a fairly substantial shell ofmetallic copper will have been deposited on the waxmodel. This can now be removed. A small hole is

_then drilled in the model at some inconspicuousposition. The model is 5arefully heated to enable thewax to liquefy and run through the hole.

It will, in all cases, as a final operation, be advisableto give the finished copper model a coating of a trans-parent varnish in order to preserve it from tarnishing.

The above process is not quite as easy as it seems.It demands care and some experience. If you run intoany difficulties with it, consult a -book in your locallibrary on electrotyping.

Water -softening MaterialT HAVE installed a domestic water -softener, and

apparently the previous owner had neglectedto regenerate according to instructions, with theresult that the softener has now lost its properties.I would be glad, therefore, if you would furnishme with the address of anyone who could supplythe necessary softening materials and also thequantity required.

I would add for your information that thesoftener in question requires regeneration after152 gallons of water at 25 deg. Clarke's hardnesshave passed through Winstanley (Maghull).IT is possible that the makers of your water -softener

may be in a position to supply you with a smallquantity of the necessary active softening material.If not, write to the Permutit Co., Ltd., GunnersburyAvenue, London, stating the type of your water -softener and inquiring . whether the material used intheir " Deminrolit " process (which produces a waterof zero hardness) will suffice for your requirements.You might also write to Sofnol, Ltd., Greenwich,S.E.xo, and to Allioc, Ltd., Bush House, Aldwych,Lotidon, W.C.2, making similar inquiries.

The precise amount of active material which you willrequire depends entirely upon the nature of thematerial. If you give the suppliers information relatingto the capacity of your water -softener they will be ableto advise you of the exact amount required.

Damp DetectorsCAN you please inform me what actuating

material is used in the construction of thesmall cheap dial -type damp detectors which areon sale at about 3s. 6d.? I have one, but thesmall piece of actuating material is broken.

What material can be used to actuate a fairlysensitive hygrometer ? I have made one, on thelever principle, using brown paper as the actuatingmedium, but it is rather large and I would liketo make a smaller dial -type one. Can you giveme rough details as to construction ?

What is the actuating medium in the Swiss typeof damp detector, in which small dolls go in andout of a house, and what is the method ofconstruction ?-J. Dimond (Bournemouth).THE actuating material of the usual damp detectorsA is generally a hempen cord which has beenimmersed in a solution of gelatine and glycerine inwater.

Dissolve t part powdered gelatine in to parts water,and then add 6 parts glycerine, together with a fewdrops of carbolic acid to act as a preservative. Soakthe cord isi this material for a few hours, then allow itto drain arid to dry. Cardboard, string, silk, wool, etc.,may all be impregnated with the above moisture -attracting solution. The Swiss -type ,damp detectorusually operates by virtue of a cord' which twists anduntwists under the influence of varying degrees ofatmospheric humidity.

None of these instruments, even the dial type, isreliably sensitive, since the actuating line, string or

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212 NEWNES PRACTICAL MECHANICSother material takes up a greater amount 9f moisturethan it readily parts with, in FoEidqUence Of Wfilebfact the surroundings of the instrument are alwaysdamper than the instrument indicates them to barYou can make a dial -type detector by using one prtwo twisted hempen lines, but we would advise you tomake a " chemical hygrometer " which utilises themoisture -attracting properties of sulphuric acid, andwhich is, in consequence, I scientific, albeit not aportable, instrument. For details of this instrumentsee any textbook of practical physics, as, for instance,E. S. A. Robson : " Practical Exercises in Heat "(Macmillan).

" Sealing Liquids"WILL yOu please tell me the composition of any

" sealing liquid " which can beaPplied overpaint and enamel to make effective crystallinelacquer ?

Having purchased a number of brands ofcrystal -forming lacquer, I fine in use that theyare not suitable for application over pre -Paintedsurfaces, perhaps because of inter -penetration.Incidentally, the brands of coloured Crystallacquer purchased do not work on absorbentmaterials. Since a sealing coat seems the requiredthing, any information you can give will beappreciated.-H. Ball (Leicester).'COMMERCIAL " scaling liquids " have various

compositions which are kept secret by theirmakers. Usually, however, these preparations aremade up on a basis of a solution of a metallic stearate,such as aluminium stearate, in, a solvent. You could,for instance, dissolve aluminium stearate in benzineor naphtha so as to make about a 25.per Unt. solution.This could then be incorporated to the extent of, say,15 per cent. with an ordinary lacquer, and it wouldcause the lacquer to dry out with a " crystallised "effect.

Alternatively, you can give the porous or paintedsurface a coating of the stearate solution before youapply the commercial crystallising lacquer. Apply toMessrs. A. Boake, Roberts and Co. Ltd., BuckhurstHill, Essex, for a copy of their leaflet cOncerning .theuse of aluminium stearate in the paint trade.

Freezing MixtdresCOULD you please publish a list of freezing

mixtures, for ;poking at home smallquantities 6f ice-creatil, etc. ? The type of LhingI have in mind is the in the smallcommercially made ice-el'ea freezers Whichwere sold before the war. I thi that the mixtut'ewhich I used in one of these freezers was twoparts of nitrate of ammonia and one part ofcommon washing soda mixed together in a smallquantity of water.

Perhaps you could suggest some other simplechemical mixtures which ars not too expensive,and which would suffice to freeze, say, a pint ofmixture in a reasonably short time.-C. F. Mander( Stoke-on-Trent).WE can tell you quite frankly that none of the many

chemical freezing 'mixtures will serve yourpurpose satisfactorily. It is not that they do not,in most cases, get down to the low temperature required,but rather that they are very expensive to make upand also that their effect is of only short duration.Hence, in our opinion, any attempt to make ice-creamby means of a chemical freezing mixture is doomedto disapPointrnent, if only in view of the cost entailed.

A good chemical freezing mixture is the following :Saltpetre, 2) lbs.Sal ammoniac, 21. lbs.Sodium sulphate, 4 lbs.Water, 8-9 pints.The pre-war success of the modern ice-cream

industry which sent out its products in tricycle vehicleswas entirely dependent upon the use of solid carbondioxide gas which was marketed (industrially) byImperial Chemical Industries, Ltd., under the nameof Dricold." This material was cheap, water -free,and it produced a very great degree of cold over a longperiod. It formed the only really practical way ofmaking ice-cream and other products without the useof ice.

We suggest that you write to British Oxygen Co.,Ltd., Wembley (or to your nearest branch of thiscompany), and inquire whether they are prepared tosupply solid carbon dioxide gas. Alternatively, youcould use liquid air, which the above company supplies(or did supply) in hired containers. A quarter ofliquid air (costing about 5s.) would remain at an extremelylow temperature for three to four days, and it wouldbe amply sufficient to freeze a large amount of ice-creammaterial, its only objection being that it would lowerthe temperature of the cream mixture too far, andthus necessitate the material being warmed up by thesurrounding atmosphere before it could be eaten. Itwould be highly dangerous to eat ice-cream materialat the temperature of liquid air.

Acetylene Gas Cycle LightingIWISH to construct an acetylene gas lightingA system for my cycle so that gas will not bewasted on short runs and the system will workautomatically. I propose to make a generator inwhich the water supply to the carbide is regulatedby the pressure of the gas generated, and all gasproduced after the lamps are put out is to bestored under pressure in a small reservoir aboutthe size of a small autovac off a ear (aboutgin. x 31in. diameter), the lamps being suppliedthrough a reducing valve. I am aware thatacetylene under pressure is unstable, so proposeto make a dissolved acetylene system for the

reservoir. f was thinking of using a pressurepf about to-islb. per sq. in. fof normal operation,though this would be exceeded by the accumulatedgas producsd after the lamps are put out. CanYou tell me at what pressure acetylene gasbecomes unstable, and how to prepare thematerial with which the dissolved acetylenereservoir should be packed ? Also, what is theMethod for estimating the volume of acetylenestored in the reservoir for a given gas pressure ?-P. Chatterley (Cosford).ACETYLENE gas is stored by being dissolved under

pressure in a paste cornposed of pure acetoneand kieselguhr, both of which materials are nowadaysabsolutely unobtainable except for uses of No. rpriority. We fear, therefore, that you will not be ableto employ .this method of storing acetylene gas, andsince the gas is not merely unstable but is definitelyliable to explode with the greatest violence whenstored at pressures of more than 3olb. per sq. in., weare afraid that you would not be justified in constructingany pressure -storage system for this illuminant. Evenunder atmospheric pressure, the . gas should not bestored in metallic holders, since it is always liable toform " acetylides," or compounds with copper andiron, which compounds are powerful detonators.

One volume of acetone dissolves about 24 volumesof acetylene, hence this substance is the ideal solventfor the gas. We suggest that you might write to eitherBritish Industrial Solvents, Ltd., Hull, or GeneralChemical and Metallurgical, Ltd., Moorgate, London,and inquire whether supplies are available of anyacetone -like solvent which could be used as a substitutefor acetone in the above respect. Your prospects ofobtaining any such compound are rather remote.

There is no direct method of estimating the amountof acetylene gas stored in solution form in a container.Probably the British Oxygen Co., Ltd., Wembley,might let you have tablestgof acetylene pressures,showing the amount of gas corresponding to a givenpressure, but any such tables would naturally beapplicable only to the standard presstre containersowned by this company.

Leaf SkeletonisingT HAVE seen leaf skeletons, that is leaves with-11- the soft parts removed, leaving only theveins.

Can you tell me the necessary chemicals, ormethod of obtaining this ?-F. E. Taylor(Edinburgh).THE usual leaf-skeletonising formula prescribes a

strong solution of chloride of lime , (bleachingpowder) in which milky solution the leaf is soaked untilthe softer parts are destroyed. The remaining skeletonis then carefully removed, washed and dried. Thisprocess, however, is never satisfactory, for the reasonthat, after a time, the skeleton itself begins to deteriorateowing to the delayed action of the lime solution.

A better way to prepare these skeletons is as follows :Dissolve so parts of caustic (soda (or " black ash ")in So parts of water. Immerse the leaf in this for threeor four days. Preferably the leaf should be a dead or adying one, that is to say, its brown colours should bewell evident. The caustic soda will dissolve out all thebrown and other colouring matters, leaving a thin,semi -transparent skin in which the " skeleton " canbe seen clearly. The next process is to immerse theleaf in strong vinegar, or, better still, in g fairly strongSolution of acetic acid (say, 3o parts acetic acid to 7oparts of water). This immersion should proceed fortwo or three weeks until the transparent skin surround-ing the skeleton is almost invisible. On washing theleaf with warm water the skin will finally disintegrate,leaving the bared skeleton, which can then be mountedOn glass.

Most workers do not proceed so far as this stage,which leaves the leaf skeleton in an exceedingly fragilecondition. They stop short at the stage at which theleaf is rendered transparent, and they mount theskeleton on glass at this stage, this mounting operationbeing able to be carried out with very much less riskof the delicate leaf structure being torn or mutilated.

Semi -matt VarnishT SHOULD be glad if you could give me a recipe

for making up flat or eggshell finish varnishto cover oil paints.-T. A. Bidford (Portsmouth).TO make a fiat famish which will dry with a semi -matt

or eggshell surface mix together equal parts ofaluminium stearate (or zinc stearate) and magnesiumcarbonate, and work this mixture into any clear oil orsynthetic varnish, employing about r part of the mixtureto, say, 8 -to parts of the varnish.

These materials can be obtained from Messrs. A.Boake, Roberts & Co., Ltd., Buckhurst Hill, Essex, orfrom any large firm of wholesale chemists and laboratoryfurnishers.

. Asbestos CementWILL you please inform me if it is possible to

make asbestos -cement ay home ? If 'so,what are the ingredients, and where can I purchasesame ?

Also, what type of mould should I need tomould it into various shapes ?-1C. A. Penn'(Forest Hill).QUITE a good cement of this nature can be made

by mixing equal parts of Portland cement andasbestos powder, and then by mixing r part of finesand with 2 parts of the cement -asbestos mixture.This is slaked with water and used in the ordinarymanner. 'Asbestos is difficult to obtain nowadaysexcept for really essential purposes. We would adviseyou to apply for supplies to Turners Asbestos Company,Ltd Rochdale, Lancs.

March, 1944You can use an ordinary wooden or metal mould

for your purpose, giving the inner sides- and outeredges of the mould a good smearing over wjth a thinlayer of a thick grease. Pressure is not essential formoulding cement articles, but often a slight pressureis an advantage.

The following (according to U.S. Patent No.1,985,764) is said to provide an excellent " asbestosmoulded plastic " :

Asbestos flour .. 4o pacts\Vood flour .. 6oSlaked lime .. 10-15

Suffazient water must be added to the above mixtureto convert it into a Very thick pasty mass. This canthen be rolled or worked as required. Articles whichhave been moulded from thii material must be stiffenedby a few days' immersion in a solution of sodiumsilicate.

Preparing Acetyl _ChlorideCAN you give me any information on how to

prepare acetyl chloride CfInCOCI alsometaldehyde j (C211403).-H. A. Petterd (Victoria,Australia).VOU will find details of the preparation of both3. acetyl chloride and metaldehyde in a textbookof practical organic chemistry, and in such a bookyou will find greater detail than we can possibly giveyou within the space of a short reply.

However, to prepare acetyl chloride, CH3C0C1,mix glacial acetic acid with half its volume of phosphorustrichloride. The mixing must be done very slowly,since a considerable amount of heat is evolved. Aftera time, the mixture separates into two layers, the toplayer comprising a mixture of acetyl chloride andunchanged phosphorus trichloride, the lower layerbeing made up of a solution of phosphorus acid inacetic acid. In .order to purify the acetyl chloride, theupper layer of liquid is separated and distilled. Theportion of the liquid distilling at 50-58 deg.. C. consistsof fairly pure acetyl chloride. It can be further purifiedby redistillation.

Metaldehyde ( Cali403), is a white solid substancewhich sublimes when heated to about 115 deg. to12o deg. C. It is readily prepared by adding one ortwo drops (not more) of concentrated sulphuric acidto ordinary formalin (formaldehyde), great care beingtaken to cool the formalin to a temperature belowo deg. C. If the temperature of the formalin isallowed to rise above o deg. C, another substance,paraldehyde, will be formed.

Pottery MakingT SHALL be glad of your help in connection with

making pottery of various types, as a .schoolactivity. The chief difficulty is the firing of theclay model, and if you could inform me as to thecheapest and easiest method of doing this-apartfrom providing an elaborate kiln-I should begreatly obliged.

Assistance would also be welcomed in choosingsuitable glazes, assuming reasonably low tem-perature baking. Would borax be an efficientglaze ?

I should be glad also to have information as towhere to obtain the best materials for this purpose-clay, colours, glazes, etc.-H. Woodcock(Doncaster).WE are afraid that it is utterly impossible for us to

give you the vital and necessary :details con-cerning the glazing of school -made pottery within thespace of an ordinary reply.

We suggest, however, that you approach the subjectas a whole by procuring either of the undermentionedvolumes and perusing them carefully :

H. & D. Wren : " Handbook of Pottery for Workshopand School." (r2s. 6d. net).

C. F. Shuts " The Potter's Craft : A PracticalGuide for Studio and Workshop." (14s. 6d.) Theseprices are pre-war ones.

In order to effect a satisfactory glaze, the materialmust be fired at a temperature of at least 95o deg. C.This necessitates a furnace the temperature of whichcan be carefully controlled. An ordinary fire is morethan useless for the purpose. Previous to the war, anumber of scientific instrument firms, such as Messrs.Philip Harris & Co., Ltd., of Birmingham, used tosupply suitable gas furnaces at a cost of about £S, butwhether these are now obtainable we are unable tosay. We should advise you to write to Messrs. PhilipHarris, or to Messrs. J. W. Towers, of Victoria House,Widnes, or, again, to Messrs. Reynold & Branson, Ltd.,Of Leeds.

Regarding glazes, ordinary borax used alone doesnot make a very satisfactory glaze, although it can beemployed for this purpose. Modern glazes are muchmore complicated things. For example, the follotifingis a typical formula for the making of a white glaze :

"Farr "StoneSaltpetreBorax .. 52Flint .. 4 >,Pearl ash.. .. 2

Grind the following to an impalpable powder:Frit (made as above) .. . Z4 PartsStone .. 15Flint ........6 White lead .. 31

Pottery clays and colours may be obtained fromMessrs. Cowan Brothers, Ltd., Stratford, London, E.,and it is possible that British Colour and Mining, Ltd.,Coleford, Glos., may also be able to help you.

We think, however, that by far your best plan is torefer to either (or both) of the above -mentioned booksbefore proceeding any further with your projects.

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March, 1944 THE CYCLIST 41

VOL XII MARCH, 1944 No. 265

Comments of the Month

All letters should be addressed tothe Editor, " THE CYCLIST,"George Newnes, Ltd., Tower House,Southampton Street,Strand, London,

.W.C.2.

Phone : Temple Bar 4363Telegrams: Newnes, Rand, London

By F. J. C.

Sir William Rootes, K. B.E., on Road ProblemsNEARLY too members and guests sat

down to lunch at the Roadfarers' Clubluncheon, held at the Waldorf on January.21st, under the chairmanship of MajorH. R. Wading, O.B.E., J.P., in the absence,due to illness, of the president, LordBrabazon. There were many distinguishedmembers and visitors present, including Mr.H. G. Wells, Professor A. M. LoW, GilbertSmith (president of the Manufactureti.Union), Sydney Camm, C.B.E., HaroldEley, Sir Harold Moore, A. Percy Bradley,Mrs. Kay Petrie, etc.

Sir William said: " As a man of Kent,when I speak of roadfafers I am naturallyreminded of the pilgrims winding their waythrough the dells and over the downs ofthe countryside. The first thing thatappealed to me was the old piltririns andthe way they travelled in those days. Travelsas they were in the past were bad, and weto -day know very little about them. Never-theless, I was encouraged by the thoughtthat if the right mentality of approach couldbe made to the subject there is treat scopefor us to be able to improve the roadfarer'slot in the future. I am sure that if the roadsin this country are tackled in a bold andaggressive way, we can bring into the life offuture roadfarers much more of the peacethan he had in the past when the pilgrimsof Kent used those roads. -

" The need for motor roads is one thatI do not think I have to stress before thisassembly, but I do feel that it is one that theGovernment authorities should tackle in theboldest way both from the point of view ofsafety, speed and the alleviation of con-gestion, which undoubtedly will be aproblem of the post-war era. I feel, also,that no stone must be left unturned at theappropriate moment to bring about thereconstruction-and the rapid reconstruction-of the roads. I am sometimes nervousthat anything in the way of a compromiseis likely to fail and not receive the full appre-ciation of the public as a whole ; what wefear is that we may get some half-baked pro-posals that would not bring us very far andwill lose a great deal of time.

" Our Prime Minister has collected aroundhim what I believe he termed ' A broadbased Government' comprising, as it does,many shades of political opinion. It is aunited Government and the burdens thatthat Government and the nation will haveto bear now that we are about to face thegreatest conflict of our life will be veryserious ones, and in those circum'stances wecan well imagine that those whose task itis to pur me the present war work will befully engaged, but, on the other hand, thereare those who serve with forward planning,and I feel to those we should appeal thatthey may make the greatest possible head-way so that when the time for reconstructionapproaches' we can be given .a bold andforward policy without further delay.

Passenger and Goods Transpprt

IF one speaks in terms of passenger andgoods transport, then it is right to

advocate that a new and progressive opinionmust be taken if we are to make the mostof our opportunity. It might be asked, whatare our -opportunities ? In the first instanceI believe that the use .of automobiles andtrucks in this country can, and should be,vastly increased. If you look up the figuresof 5938, ,,ou will see there were 2,490,000cars and commercial vehicles in use in thiscountry, This represents I in 23 of ourpopulation, whereas in California it wasI in 3.6, and even in, our Dominions, forinstance, take New Zealand, it was t in 6,and in Australia I in 9. I think that thesefigures indicate that there should be a fulleruse made of wheeled vehicles whether forindustrial or domestic purposes, as they areessential to the efficient conduct of our newnational life.

" For goods carrying vehicles, particularlyfor economic hauls, I hold the view, and Ihope my friend, Mr. Birtchnell, of theMinistry of Transport, who is here to -day,agrees, we must make more use ofCommercial vehicles. In the past we havepermitted one of our greatest potential assetsto be hindered and given a back place in ourinternational life. Successive Governmentshave allowed an obsolete method of taxationto 'hinder and to hamper the UnitedKingdom in the production of cars and light

-commercial vehicles of the type that werein demand by the great majority of usersthroughout the world. In addition to this,they have also taxed the road users at sucha prodigious rate that transport generallyhas been thwarted and not allowed to expandat the rate it should have done.

" Sir John Anderson's statement in theHouse this week is therefore all the morewelcome, and it is to be hoped that he andhis colleagues will encourage the traveller inreviewing this matter by taking the broadestpossible view of the subject they can. Ishould also like to see, as far as both " theMinistry of Transport and the Board ofTrade are concerned with this problem, thatMr. Birtchnell will not fail, when he isnext back at the Ministry of Transport, toappreciate that viewpoint also.

" Commercial vehicles, to my mind, mustbe freed from some of the shackles they havearound them to -day, shackles which havebeen imposed on them with a distinct inten-tion of holding them in bondage. Gentlemen,I think we have to appreciate in road trans-port that when it comes to road haulage,motors are definitely handicapped, and if thishardship is not removed it is impossible forthem to be efficient in the postwar era.

" In the .past it was thought that railwayscould not be successful if other forms oftransport were not robbed of their 'rightfulplace in a progressive world.

" I hold the view, and I am sure you willagree, that railways must be successful andthat it is the duty of every citizen in thiscountry to see they are successful. I believethey can be, but I unhesitatingly say that ifthe public are to be asked to use stationsthat are cold, bleak, untidy and unfit to use,and trains that are out of date in appear-ance and lacking in modern comforts, thenthe railways will need to continue the policythey have been pursuing during the past fewyears, which is, to endeavour to handicapother forms of transport which are of a moremodern type.

Postwar Rail Traffic

"ON the other hand, if- the railways are

given the opportunity of modernisingtheir equipment, then I am convinced thatindustry and the public will use them to evena greater ement for post-war goods andpassenger traffic. From a national point ofview, I think we should be agreed that weneed to see that all forms of transport areefficient I hope thatMr. Birtchnell, from the few remarks Ihave made, will realise that, in the motorindustry in particular, we are not in anvway opposed to the railways. We are alllooking forward to the opportunity beinggiven by both the Government and therailways of sitting around tables andcollaborating and endeavouring to work outa future which will be of benefit to thepeople of this country.

" Gentlemen, it is to be hoped that ourGovernment will take a realistic view ofthe whole of this problem, and that when westart again we shall not commit the errorsof the past.

" One of the major tasks we are confrontedwith is the re-establishment and advance-ment of our trade in general, particularly inrespect to our overseas and export trade.Under the new economic conditions we willhave to face, this will be one of the vitalplanks in our future policy.

" By heavily taxing private passengercars, public conveyances and transportvehicles in general, I am convinced that theGovernment have imposed a recurrentburden on every phase of trade and indus-try, including agriculture. A .burden likethat, if allowed to remain, will be a handicapin building' up our industrial effort and ouroverseas markets. Nobody to -day can havea greater influence over those matters thanthe Minister of Transport, and when I saythe Minister of Transport I also mean thosewho_ are around him. They are in a uniqueposition because they not only control roads,they control road and rail traffic, they con-trol shipping and the canals, and, I presume,if we have a correct grouping of transport,in the future they will also have a big sayin matters concerned with the air.

" Upon Lord Leathers's shoulders, there -(Continued on page 48.)

42 THE CYCLIST March, 1944

PARAGRAMS

Neidpath Castle, on

Regional RecordWITH a total of 5,879 bednights during the year" ending September 30th, 1943, Winchester Y.H.A.set up a new regional record. The London Region'stotal for the corresponding period was 5,60o in excessto 1942.

Povey at PortsmouthERIC POVEY, Marlborough A.C. and North Road

C.C., stationed with the Royal Navy on thesouth coast, is a keen attender of Gosport C.C. fixtures.

Ridley C.C. News

4- the R.A.F. in Southern Rhodesia, has beenpromoted to pilot officer.

Home from AfricaTHOlVIASIMARK, Barras Road Club, is home after

many months' service in North Africa. He metseveral of his club -mates while abroad.

" Early Bird" PathfinderSERGEANT JOHN WALKER, Early Bird C.C.,

is now on duty with an R.A.F.,Pathfinder squadron.

Barnesbury C.C. Record -

EIGHTY members of the Barnesbury Road Clubare serving with the various armed Services ;

three have lost their lives at sea. A correspondingnumber of members are prisoners of war and another,William Toddle, has been " missing " since June, 1940.

Died in ItglyAA MEMBER of Glasgow Lancia C.C., Gordon

Stewart, has died in a hospital in Italy. Hewas serving with the Royal Engineers.

The Sergeant's ReturnOGMOFtE Valley Wheelers, a Welsh club, recently

welcomed home from service in the Middle East,Palestine, Syria and India', Lance -Sergeant W. J. Jones.Royal Artillery, one of the club's founder members.

Barnet a Mixed ClubBY resolution passed at the annual general meeting,

the noted Barnet C.C. has decided to admitladies to membership.

Chichester ReunionAFTER being with the Eighth Army throughout

its long campaign, Sergeant Leslie Osborne,Chichester C.C., has been home on leiwe, as has hisclub -mate William Long (Fleet Air Arm), who hasbeen stationed in Gibraltar.

Wally Reynolds KilledWHILE on his final flight before taking a commission,

Flight Sergeant Pilot Wally Reynolds, SwindonWheelers, was killed while engaged in operations overGermany. He was very well known to West Countryclub -folk.

A Cycling PresidentARTHUR ROGERSON, Spen Valley Wheelers" president, takes a very active part in his club'sriding activities.

the Tweed, Scotland.

Frank Tillman DecoratedFORMER treasurer of the Finsbury Park C.C.,

Frank Tillman has been awarded the Polish Crossand bar for his part in shooting down two Ju. 88s. Hehas also been promoted to pilot officer.

Clubman's PromotionFORMER member of the Crouch Hill C.C., and

later of the Finsbury Park C.C.. Robert Lashamhas been promoted to pilot officer. He has taken partin many operational sorties.

Alex Hendry's HaulALEX HENDRY, Glasgow Wheelers, closed last

time -trial season with a total of 45 road prizes.In addition, he won numerous track awards.

New Scottish OfficialsFOLLOWING the retirement of Alex Urquhart

(Glasgow Wheelers) and A. McArthur from thechairmanship and secretaryship respectively of West ofScotland T.T.A.-positions each has occupied sincethe outbreak of the war-Harold Briercliffe and FrankHuggins have been elected to fill the respective offices,

A " Twelve " for ScotlandDOUGLAS C.C. (Scotland) anticipate promoting a

12 -hour event this year..

Notts Castle B.C. Revival?AMOVE is afoot to resuscitate the famous Notts

Castle B.C. which, two decades ago, providedopen events attracting the cream of competitive riders.

Pickersgill in UniformH. H. PICKERSGILL, Veg.C. and A.C., is among

the latest famous cyclists to join the Forces.

Tom Hughes's Mileage,

TREE ainous Wigan " evergreen "rider, Tom Hughes,A covered over ie,000 miles in 1043. Since he

Passed his both birthday he has recorded fiver 170,000miles and has ridden in almost every European country.He has been riding regularly since 1887.

Romford Wheelers Talk BusinessROMFORD Wheelers' annual general meeting

revealed that from the five members who wereleft after the general mobilisation of the club's youth,membership had grown to 53.

Charles Davey HonouredCHARLES DAVEY, famous record breaker and

one-time Olympic rider, has been elected lifemember of the Addiscombe C.C., of which lie ispresident.

Met in AfricaUUBERT WHITEHURST, Wolverhampton City" C.C., has met in North Africa " Clarry " Hopkins,Crewe Wheelers, against whom be frequently raced.

Fred Willett Presumed LostXTOTIFICAT ION has been received from the AirAN Ministry that the death on active service must bepresumed of Fred Willekt, popular Norwood Paragonrider, who has been missing for the past eight months.He was an R.A.F. Sergeant -Observer.

Allondon Road ClubTHE Allondon Road Club, which formerly con-

tributed many notable riders to the sport, hasbeen resuscitated.

Manufacturers' PresidentC. GILBERT SMITH has been elected president...° of the Manufacturers' Union for the fourth con-secutive year. George Wilson, 0.13.E., A.F.C., J.P.,and A. E. Dovey have been elected vice-presidents.

Forest C.C.DESPITE the fact that 75 per cent, of its members

are in the Forces, the Forest C.C. is . beingrevived. It promoted classic open events before thewar.

Albert Watson RememberedFRIENDS are opening a fund to commemorate the

memory of Albert Watson, famous Scottish riderand tricycle record holder, who died in Canada while .

serving with the R.A.F.

Scots AwardsAWARDS won in the Scottish championship last

season were presented at the Douglas C.C.'sprizegiving in GlasgoW, when Alex. Hendry, GlasgowWheelers, took most of the prizes.

Ben Nevis Railway?rORT WILLIAM Town Council has proposed thatA- a mountain railway be run up Ben Nevis, thehighest peak in Britain, 4,406 feet.

Canal ClosingA T one time regarded as the shortest, straightest," and deepest canal in England, the mile -and -a -quarter -long Ulvcrston Canal, in North Lancashire, isto close.

No ChangeALTHOUGH attempts were made to increase

charges, the annual council meeting of theScottish Y.H.A. decided to continue the present chargesfor membership and overnight stays.

Situations VacantAPPLICATIONS are invited for the post of part-

time Secretary to the Road Time Trials Council.(Women must be exempt from National Service.)Applications, stating experience of road sport, qualifica-tions for administrative post of this nature, timeavailable, and salary required, should be sent to S. R.

Surrey.1, Glenwood Road, Stoneleigh, Epsom,

ClubMaxfield MissingVLIGHT LIEUT. W. W. MAXFIELD, nogL. sprint champion of England, is reported missingfrom an Atlantic operational flight.

Lonsdale in MidlandsFRANK LONSDALF., the Douglas C.C. star, has

been training with the Navy in the North Midlandsand has met such outstanding racing men as DouglasHartley, C. Cartwright, and C. Gorman.Death of Bill Pinder" BILL" PINDER has lost his life while serving

with the R.A.F. as a Flight Engineer. He wasa Yorkshire Vegetarian C.C. official, as well as anenthusiastic Clarion member.

More for OldhamTHE Oldham and District Cyclists' Union is now

stronger than at any previous part of its history.Most of the leading Manchester and South Lancashireclubs are affiliated, a recent recruit being the CheshireRoads Club.

NotesMid -Scotland OpensTEN opens will be run this season in Mid -Scotland,

as well as a women's " 25 " and two hill climbs.This is a longer programme than in 1943-Clario4 OpensTHE West of Scotland Clarion will run open events

at 25, 5o, and too miles this season, as well asthe "'four de Trossachs " hill -climbing time trial.

Open to AllTHE Barnet C.C. has opened its ranks to women

riders. Formerly this noted North London bodywas confined to men.

" Twelve" for ClydesideTHE West of Scotland T.T.A. will be running an

open " 1z -hour" this season for the first timesince the war. Additionally, the Association is enteringa new field by promoting a " 25 " for women.

Addiscombe " 30 "THE Addiscombe C.C. will be running its opeti

" 3, " again during the coming season.

March, 1944

AroundWhat is a Real Cyclist?T WAS interested to read a short time ago11 a definition of what the writer of thearticle considered to be a " real " cyclist.According to him, a real cyclist is one who

. cycles in all weathers, every day of theyear and on every possible occasion, whothinks of nothing but cycling, who, is forever advancing the cause of cyclists, andmore or -less lives on his bicycle. Now thissort of nonsense has been written and spokenso many times during the past 3o yearsthat it is time it was debunked. The mostreprehensible type of cyclist is that definedabove. Fortunately, however, I doubtwhether there is such a cyclist in existence.A cyclist who states that he enjoys ridingin the rain .is a liar. A cyclist who electsto start on a cycling journey in the rain(provided, of course, he has not an appoint-ment to keep which cannot be postponed)is a fool, and one who makes a fetish of ridinga bicycle every day to provide himself witha boast about the number of miles he hascovered (and thereby, when walking, takesthe permanent attitude of one riding abicycle, shoulders bent forward) is a candi-date for an asylum. To promote this sortof insincere belief is to do the greatestpossible disservice to cyclists. Godyfin rodeevery day the whole year round as hard ashe could, and he told me he was not anxiousto repeat the experience.

Of course, the contributor omitted to saythat a' " real" cyclist must have a hatredof motorists, that he must not use cyclepaths under any consideration, and that hemust oppose all forms of legislation. Addi-tionally, when visiting the wayside teashopshe should conduct himself as a hooligan,parking chewing gum on the furniture,creating a din, and possibly breaking upthe crockery. He should, of course, regardteashops as places where you go to. harrowa cup and saucer, a plate, knife and fork,by means of which you can drink the liquidin your flask and eat the sandwiches whichyou have brought. He must, of course, joinevery cycling organisation,

A Definitionj WILL give you my definition of a11 " real " cyclist. It is one who cyclesfor pleasure when the mood fits him. Hedoes not necessarily wear plus -fours, becauseScottish artists always draw cyclists in plus -fours. He does not wear plus -fours whenhe is not riding his bicycle, as so many doto proclaim the fact that they are cyclists.He does not wear half a dozen club badgesin his lapel. He is not anxious to pile upmiles, but pleasure. He does not ridethrough the rain unnecessarily. It is badfor the machine, anyway, and possibly forthe health.. He does not necessarily belongto an organisation, for this is riot a sinequa non. He does not hate motorists, and ifit is more pleasant to use a cycle path, hewill use it. He will be reasonable in argu-ments, and not oppose things for the sakeof opposing them. He will not wear colour-ful and fantastic clothing, nor imitate theracing attitude of a , cyclist. He will notnecessarily want to cycle amongst, mobs, andhe will be of clean appearance.

Now there are hundreds of thousands ofsuch cyclists amongst the millions on theroads ; they do not belong to the noisyminority and so their praises go unsung.Thry do not spend a large part of theircycling, time arguing cycling politics ; and

THE CYCLIST 43

the WheeliworidBy ICARUS

they have their own views, not the viewsmass-produced ad museum by nationalbodies. They do not oppose things just forthe sake of opposing or because they wereopposed in 1888. I know a few real cyclistsof the right sort who have been cycling forover 3o years; they do not belong to acycling organisation. Of course, a clubmanis chiefly interested in racing, and there are,of course, those who like riding in company,but there are far more who prefer to ridealone.

Let us hear less nonsense, or rather tripe,about " real " cyclists, or " really " cyclists,and less about touring with half a comb anda toothbrush, borrowing or stealing the hotelsoap! I challenge the writer of the para-graph to show me a real cyclist who fitshis definition. I can show hint thousandswho fit mine.

Road Accidents-December, 1943THE number of deaths resulting from

road accidertts in December, 1943, was69o-the highest monthly total of the year.In, addition, 11,537 persons were injured,3,15o seriously. These figures compare with78o killed, and 12,859 injured in December,7942.

More than half the accidents occurredduring darkness, and among adult pedes-trians the proportion killed at night was ashigh as three out of four. On the otherhand, accidents to children, most of whichoccurred in daylight, caused fewer deathsthan in any month since the previousJanuary. The total was 77, of which 68were pedestrians.

As daylight lengthens, accidents to childrentend to increase, and the Ministry of WarTransport reminds all parents and road usersof the need for taking the greatest possibleprecautions, including the regular trainingof children in kerb drill.

The figures for December bring the totalnumber of road deaths in 1943 to 5,796.Although this total is the lowest for manyyears, the number of children killed, 1,124,is well above the pre-war level. The totalnumber of injured of all ages during theyear was 116,740. The following is a tableshowing the total of road deaths for theyears 1938-43 inclusive, together with thosefor child pedestrians and child cyclists.

1938 1939 1910 1941 1942 1943

All persons... 6,048 8.272 8.609 9,169 6.926 5.796

Child 870 850 972 1,231 1.112 903pedestrians (app.)

Child cyclists 205 184 206 231 203 191(app.)

Lt. -Col. Chas. Jarrott, O.B.E.THE passing of Lt. -Col. Charles Jarrott,

O.B.E., is a' great loss to the RoyalSociety of St. George (of which he wassecretary for several years), the Roadfarers'Club and several other clubs and societies.He was a founder member of that pioneerbody, the Nineteenth Century Circle ofMotorists. He was also a member of theFellowship'of Old-time Cyclists. To me hisdeath came as a great shock, for we werefriends of over forty years standing. Inthose far-off days, when the motor industrywas almost entirely in the hands of Con-tinental firms, and its development in thiscountry was retarded by repressive legisla-tion, Charles Jarrott was one of that bandof hardy pioneers who helped to bringEngland to the fore, for he competed withsuccess in the big road races abroad against

the giants of that period. But he will bestbe remembered for his activities in connec-tion with the Automobile Association. Beforeits foundation, when motorists had to submitto considerable persecution by the police,he conceived and carried out the idea ofengaging a squad of boys, each wearing anarmlet as a mark of identity, to stand at thedanger spots on the roads and warnmotorists of the proximity of police traps.

From this modest beginning, due largelyto the vision and abounding energy ofJarrott, grew the vast organisation we knowto -day. The Automobile Association, ofwhich- he was chairman for several years, isan enduring monument to his memory.

To -day we mourn the loss of an ardentRoadfarer, a great sportsman, and a man ofvery lovable personality.-E. Coles Webb.

Fountain C.C. 1944 OfficialsGen. Sec., G. T. Avis, 44, Badminton

Road, S.W.I2 ; Treasurer, Miss E. Butler,17, Eckington Gardens, S.E.14. Racing Sec.,H. Patman, 113, Tivoli Road, S.E.27.Runs Captain, S. Chalmers, 63, Lough-borough Park, S.W.9.

H. Patman is dealing with inquiries, entryforms, etc., for the Balham R.R. 25, whichthe Fountain C.C. are promoting shortly.The usual Kent and Surrey lanes course isto be used on the usual week in lateFebruary, and offers to marshal this diffi-cult course will be much appreciated.

The annual dinner and dance, held onFebruary 26th, was very successful.

The Road Time Trials Council

IVIR.A. E. ARMSTRONG, chairman of

11 the Road Time Trials Council, wasalso elected chairman of the National Com-mittee at a meeting held on Sunday, January23rd.

The main business of the meeting was theconsideration of matters arising from thedecisions reached at the National Councilmeeting.

National championships will be held in1944 at the following distances: 25, 5o, toomiles, 12 hours and hill climb. One eventat each distance will be allocated to districtcouncils in different parts of the country, anda ' district council to whom an event isallocated may delegate the promotion to aclub in its area. Full details concerning thepromotion of the championship events willbe given shortly, but the main provisionswill be that the events must be timed onsplit-second watches holding current Kew" A" certificates ; entries will be limited totoo riders both an individual and teamchampionship will be decided at each dis-tance, but the riders will be selected onindividual merit, without regard to teamrepresentation.

The national best all-rounder competitionwill be based on average speeds at 25, 50and too miles. The events to be includedin the competition are under consideration,and a further statement will be made assoon as possible. Not necessarily all theevents to be promoted in 1944 will beincluded in the competition. It may bedecided to limit the competition to a certainnumber of events at each distance. It wasdecided not to include the 12 hours distancewhile war conditions prevail.

The amount of the levy on each rider inopen and association events has been fixedat 3d. for each event This amount is tobe added to the entrance fee\ and forwardedby the responsible official of the promotingclub to the district council treasurer.Cycling Instructors

SPECIAL instructors of cycling, as ofcricket, football and boxing, have been

suggested by the National Committee onCycling to the Board of Education. ve

Sheepstor,Qartmoor village.

New Owners

44

WaysideThoughts

.zyF. J.URRY

;NUMEROUS amalgamations have lately taken placein the cycle trade, led by the absorption of Rudge-

Whitworth by the Raleigh interests, soon after whichthe B.S.A. Co., Ltd., bought the New Hudson andhave since acquired Sunbeam ; and J. A. Phillips andCo., Ltd., have purchased Armstrong. Cycles, Ltd.These are facts ; but rumour is busy with many well-known names, and I understand various other amal-gamations are likely to take place in the near future.It is not surprising that with the end of e4se war insight, great firms are busily planning tit output fortheir extended factories, nor do I think the changeswill be other than beneficial to cycling interests. I amtold on good authority that these absorptions will notaffect the specialities of the machines for which theabsorbed firms were responsible, but that the amalga-mations will enable the widest possible field of demandto be covered. If this works out in practice, thencertainly we can be sure the result will mean the highprobability of a fine range of better class bicyclei.'Think of the old Rudge. I once owned one weighing281 lbs., a very beautiful bicycle, that carried methousands of happy miles in the early part of this century ;and I still own and ride a little e.unbeam, now in itstwenty-third year, and still making the daily winterjourney without complaint. Only a few years ago Igave a New Hudson away that had outside liners to themain tubes, an introductiOn to lightness, strength andrigidity that was first used by the late F. J. Osmond onhis famous machines. One hopes these things will

. be remembered by the new owners of those famousnames, not for the purpose of reversion to type so muchas the modernising of the bicycle to be a worthy successorto those that built a great and remembered reputation.There is still much room for improvement, and one hopesthis object is in the minds of the new owners of the oldnames.

The Constant JoyI BELIEVE there will be a big demand for the

good type of bicycle in the post-war days, firstlybecause we are all rather tired of the dead level of qiialityimposed by war conditions, and secondly for the simplereinin that economy in travel will be essential andmany of us who could just afford to run a car in itnowill now find that financial burden impossible, and sowill be looking for the very best the cycling world cabsupply. To the fit and active this limitation will be afine thing, since it will replace the car as a purveyorof fresh air and scene, and add that inestimable advantageof exercise and the feeling of complete freedom that isohly to be found ins elf propelled travel. (`liven the rightbicycle and the eoffeet way of riding it, the ordinarilyactive individual ought to be as happy as the day is long,and gather to himself a good deal more personal satis-fiction at the end of it. People say it is all very wallfor me to talk like that ; I aril used to it, &nil that makesa difference. Of course it does, but I had to get used foit once, and so can they. It is merely a question ofovercoming that silly notion that there is aornething thematter with the man who rides a bicycle. and thatmatter is mainly because it is felt he can't afford any -

THE -CYCLIST

thing betterI And the worst casesof this kind of snobbery are amongthe people to whom the limitations aretrue. Get rid of that feeling, for theonly thing in it is worry and a conditionof covetousness that is worse. A goodbicycle and the ability to ride it easilyis the greatest health and happinessasset I know, and I am prepared to sayso in any company and under the mostvirulent form of criticism. The cycletrade arid the cyclists have never saidit half seriously enough, perhaps. becauseit is the truth, which too often is takenfor granted. There is much moreconstant joy to be extracted fromcycling than any other game I know.

The Easy RiderTHE comfort of riding to work instead

of waiting in the rain in the. busqueue has to be experienced to bebelieved. Anyhow that is how I feel asfar as this provincial city of Birminghamgoes, and what happens here in theway of traffic is probably no better orno worse than in most cities. I knowthe taped cyclist sliding past thewaiting crowd seems to many of theman -object of pity because I have heardsuch remarks paSsed on numerousoccasions ; but asfar as I am concernedthe pity is all for the other fellow whosejourneying is nearly always uncomfort-able, and for ever at the dictates, of time.Mine is when I like, and as for the rain,it just makes the difference of a pair ofleggings and a cape, and nothing else.I know, too, that many riders give uptheir daily journeys when the weatherturns rough, for they do not stop tomeasure the loss of regular convenienceagainst the occasional struggle againstwind and rain; if they did I thinkthey would absorb my philosophy, andbe the better in health and temper forthe experience.. The only conditionsthat deter me from my daily journeyingsare more than an inch of snow and that0... glazed frost condition of the roadswhen the slightest deviation from astraight course means skidding, andthat is particularly dangerous becausethe car ahead or behind you is in

the same jeopardy and may " bump you off " withoutthe application of carelessness. Taken all round mydaily rides are an enormous saving of time and a tre-mendous convenience, to say nothing of the value ofregular exercise and the economy. If offices hadparking places for bicycles I believe their regular usewould be enormously increased, and we ought toagitate for them in the same way we are now agitatingfor cycle storage room in the houses to be built afterthe war. We have a fine servant in the bicycle, but wehave not given it the best chance to prove its highestvalue.

Registration RacketTHE police voluntary registration of bicycles goes

on apace, but what good it will do to stop thethief has not yet been told to us. When the experimentwas first launched-by the Portsmouth Chief Constable,I believe-we were told the Cases of theft fell awayenormously. Natural enough, for the professional thiefjust waited awhile to see what effect this voluntaryregistration would have on his business. Now I under-stand-though not officially-that with the lapse of timesufficient to show the thief he has nothing to fear fromthis " check-up," the number of stolen bicycles has goneback to normal. One would expect that to happen, forthe registration of anything will not prevent it beingstolen. If only cyclists would take the little trouble topreserve the maker's number stamped on their machines,ready to hand to the police, together with a descriptionof its latest equipment, .in case they are unfortunateenough to have it stolen, that would be far more valuablethan registration-voluntary or otherwise-for it wouldsave the police much clerical work (which in mostcases would he out of date) and the owner would bein a position to hand to authority an up-to-the-minutedescription of his property. That obviously is the rightmethod of check-up in case of loss. If this voluntaryregistration business is allowed to " get away " withthe story, you can take it as a certainty that compulsionwill follow, and that definitely means 'some form oftaxation, and once a registration fee is imposed, whoshall say where the impost will stop ? Remember, formany years motoring interests hate voiced the opinionthat all cyclists should be taxed and made to carry anumber plate I Do you think such opinions will beqbieted by any form of voluntary regiltration ? .1don't.

Answer to the Cycle ThiefACTUALLY the best thing for the prevention of

cycle theft is a built-in locking device, and theneatest thing I have seen in this way will be marketedby the B.S.A. Co., Ltd., immediately after the war.The company would not be waiting for the cessationof hostilities if they could obtain the materials and thelabour to operate their patent device now, for theyrealise how important the queition is, and the fact thatthey possess a complete answer to the cycle thief,which cannot now be marketed, is galling. Actually,I have one of these locks fitted to a machine I own,and guarantee you would not readily discover itsposition, for it is remarkably unobtrusive and neat.

March, 1944The lock is fitted in the crown fork and operates a boltin the steering column by the turning of a small Yalekey when the front wheel is at a slight angle. It ispositive in action and cannot be tampered with exceptby dismantling. Only when the lock is in operation canthe key be withdrawn, a safeguard against the loss ofthe key when the machine is doing'its rightful service.The weight of the whole device I should imagine is notMOM than a couple of ounces, so that the fitment isSuitable for every type of bicycle, and is as simple tooperate as it is neat and sure. This is the sort of " extra "regular cyclists have been looking forward to purchaseever since cycle thieving became a profession, and, inmy opinion, it justifies the description of a completereply to registration and that curse of dishonesty, thecycle thief. Some years must elapse before its usebecomes universal for, as at present designed, it is abuilt-in job; but the fact that the answer to all thisregistration nonsense is ready to market with the endingof the war, is one of the satisfactory things in cycledesign and improvement we are waiting for.

Waiting For ItTHE war news is such that it gives one hope that the

European theatre will close down " beforeanother winter is on us. We all hope and desire thatfact, for the relief from all our present daily troubleswill be tremendous. What will hanpen, thereafter is aspeculation agitating the minds of most thinking men.For myself, I imagine cycling will go forward in awonderful way, not merely as a result of its own intrinsicvalue, but because the economic position of most ofus will be such that will suggest the use of the cheapestform of transport, but not, I hope, the cheapest typeof bicycle. Surely we have had enough of the latterduring the war when the manufacturing firms did theirbest, but were by no means proud of their products.What we shall need when peace comes to us is lighterand brighter bicycles, multi -speed geared, well saddled,and replete with stainless rims ; bicycles to be proudof, and to ride with the conscious certainty that wepossess a piece of marvellous machinery giving us awide freedom and a way of health at a cost within theeasy reach of millions. Personally, I have no doubtsabout the matter ; my only trouble is to find the powerto put over the story to those same millions wholanguish their leisure in dull places, and know not ofthe beauty and splendour a bicycle-and particularly agood bicycle-can give them. No doubt, even whenpeace comes tons, things will be difficult in the earlydays. We shall have to wait a while longer for the hestin bicycles: our caterers will need to get into theirstrides again before that ultimate glory of cycling, theholiday tour, can be considered completely comfortable ;but the start of peace will, I think, be the beginning of awheeling epoch the like ofwhich has never been seen.Yes, I believe in cycling because I know cycling, andto know it intimately is to love it intensely as a giver ofjoy.

Repeating HistoryAMONG the numerous letters I receive from

interested readers many contain suggestions/ forthe improvement of cycle design, and it is remarkable toobserve that a high percentage of them tabulate notionsthat were tried out long ago and found wanting, or, atany rate, the then wheeling public would not have them.There is no point in enumerating the ideas propounded,for that would merely be waste of space ; but it isinteresting to note that successive generations of ridershave found their inventive minds directed to similarthings. Personally, I do not think we have reachedlimitation of design in bicycles, for there are manyavenues open to welcome improvement, but I do think,we are unlikely to see any major alteration commensuratewith the Dunlop tyre or the original S.A. 3 -speed hub.I have lived in the world of wheels long enough toremember the coming of the Dunlop and the sensationit made, and to now realize that event was " a once ina lifetime " happening, for even the S.A. gear and theBowden wire cable did not stir imagination and trade asdid the pneumatic. Several of my correspondinginventors are keen on lengthening the throw of thecrank in

theforward movement, and reducing the

travel of back stroke, and if it gives them anysatisfaction, that has been the aim of thousands ofpeople. It can be done, but only under handicaps ofweight and very considerably increased cost, and it isdoubtful if the gain in power, even if obtained in a verysimple form, is worth the additional cost, °or-moreimportant to me-the upsetting of the easy rhythmof the pedalling action as we now know it. If there isany compensation in growing old, then some of itresides in watchinghistory repeat itselfand discoveringthat mankind stum-bles on most goodthinis by accident.

"Holidaysat Home "

Many of us willbe spending " holi-days at home " this

\ year. There isnothing like going --right away on one'svacation, but if thiscannot he managed,thed a daily ride oftanything up to azoo miles, makes agood substitute.

rj

March, 1944 THE CYCLIST

CYCLORAMA

A glimpse of Tintern Abbey, Monmouthshire.

Synthetic Rubber TyresEVER since the loss of the Malayan

Rubber Plantations and the need forrubber economy, we have heard a good dealabout " Synthetic." It has always beensurrounded by a certain amount of mystery,this question of the " substitute " for naturalrubber, but I am glad to see that tyre -usersare being given some hints about the useof tyres which contain some proportion ofsynthetic. And, what we have to do,apparently, is to see that such tyres areinflated hard, and kept hard. Simple enoughadvice, and really nothing different fromthat which tyre manufacturers have alwaysgiven us . . . but we -have so often neglectedit! Well, I am told that it is just impera-tive to keep tyres hard when they have beenmade partly from synthetic . . . the penaltyis-greatly reduced mileage! So wisecyclists now know what to do and will do it.

Cycling ParsonsMY recent comments about an aged

Derbyshire rector who bought a newcycle, and took good care to buy a goodone, so that it would last, have brought meone or two 'letters from cycling parsons ofadvanced age. It appears that countryparsons live long, and that they are keencyclists . . . and I doubt not that the cyclinghabit has had much to do with theirlongevity! But when one comes to thinkof it, it is obvious that the country parsonhas a job which renders possession of abicycle a sheer necessity ; what better modeof transport for " doing the rounds of theparish " than a bike ? It would be interest-ing to know of the very oldest cyclingparson!

Lure of the Dart -boardCAME, on a moonlight night, to a village

in Hertfordshire where there is a good

and ancient inn. And inside it there is alittle low-ceilinged room sacred to the gameof darts. And I can never resist the lureof a dart -board, so I sought a game . . .

and how good it was to play this fine oldgame with some old village worthies who,despite the fact that they worked and livedquite near to London, nevertheless were truecountrymen . . . speaking the country dialect,thinking country thoughts, and looking uponlife through the eyes of the land, the cow -byre, the rick -yard, and the green meadows.And what worthy exponents of the gamethey were! If a townsman, fancying himselfan adept at this old English game, everthinks that he is necessarily superior to thecountryman, let him enter some inn in ahamlet and try his skill against the " locals."He will very likely get a great surprise!After our games, I sat and smoked, andsipped ale with two of the villagers, andfound them up to date in agricultural politicsand full of optimism about the future of theEnglish farm. And I cycled towardsMother London happy and optimistictoo. . . .

The Cotswolds in SpringFEBRUARY! And although it may still

be winter, I find myself thinking ofspring, and wondering whether I can stealaway for a day, and go to my belovedCotswolds, and look for snowdrops! I lovethose little virginal blossoms which seem toherald the arrival of all the floral hosts tocome . . and I used to know just the dell,nestling in the very heart of the Cotswolds,where I could always he sure of findingthem . . . and in February, too. Not veryfar from Stanway and Stanton Court . . .

and if you know those delightful Cotswoldplaces you will know why I long to visitthem again. - .

By

H W. ELEYThe Last Cycle Show

.LOOKING over some business photo-graphs the other day I came across

a collection of pictures taken at the lastCycle Show to be held prior to the outbreakof war. What memories they brought back !Hard, urgent, unremitting toil to get" stand " ready for the opening! Problemsof display, memories of crowds touring theexhibition, of speeches about the cycleindustry.. . I found myself wishing thatI was again in the thick of " show prepara-tions " and longing for that good day whenit will all be possible again. May it comesoon!

Literary ChatterALOVE of cycling is often allied with

a love of literature, I find, and , justlately I exchanged " literary chatter " witha cycling friend, and found that both of ushad been indulging in a sort of " course "of the classics. Both of us had grown alittle tired of " thrillers " (though I confessto an abiding love for them!), and, curiouslyenough, both of us had turned to the sameold book for quiet joy and instruction ;Cobbett's Rural Rides. I commend it toall who would know more of their England,and who love to read of the English sceneand character. At the moment I am dippingonce again into Pickwick and finding, asevery Dickensian ever does, that it isinexhaustible in its allure, and unsurpassedin its power to charm and 'entertain. Oh,for those spacious Pickwickian days, whentables groaned 'neath the, weight of boiledfowls, and gargantuan pies, and mounds cfcheese, and bottles of claret, and port andbottled beer! Oh, for the inns of Pickwick'sday, when landlords greeted the applicantfor a bed with beaming smiles, acid straw -chewing ostlers sprang from the dim cornersof stable yards to take one's horse and giveit " good stabling." The days are gone . . .

but Pickwick remains, and we can journeyand laugh with. him still.

Road AccidentsTHE death -on -the -road figures are still

tragic. Many factors account for thestill far -too -high figures, but I wonder some-times whether parents are as thoughtful andwise as they might be in connection withthe use of the roads by small children. Thechild on a toy cycle can be, and often is,'a real menace to other traffic, and I haveseen many children, riding who have nocontrol of their small machines, and who arequite unfitted to be allowed on a modernroad. And when one meets groups of thesekiddies, cycling happily but carelessly toschool, one feels that legislation should takea hand and forbid them the road. Now, nowails about "freedom," please! There isno freedom in folly!

Brighter Shops!

MOSTof our shops-and I include cycle

shops-need a coat of paint ; they aregetting shabby after over four years of war!But I know the difficulties, and so just sighfor the day when we shall be able to smartenup our shops, and put in colourful windowdisplays, and say good-bye to this drearydrabness which is not the least of the badthings which Hitler has brought upon us.Meanwhile, I think that traders do theirbest, and I have seen some quite ingeniousefforts at window display . . . " home-made "efforts which show that the zeal and theenterprise of our retailers is not dead .

merely sleeping an involuntary sleep!


4

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....711/C)erbtl . . LTS

AWHEEL

IN SAFETY

When you obey the call of the open road' be sure

that you can rely on your brakes. Wet or fine, on

steep hill, dangerous cross-roads or treacherous curve

you can rely on Ferodo All-weather Brake Blocks.

In all emergencies they grip firmly and noiselessly

giving confidence and safety along every mile you

ride. Be sure to fit

ALL-WEATHER BRAKE BLOCKS

REGO Tree...De NI R.%

IF,010101D F ER ODO LIMIT Ell, CH AP EL- E.:\ -LE -FRITH

March, 1944

tZ

St Mary the Viers. e'adderbary(Osoa.)r Stn.&

Dazzle, and Deep WatersN that part of the world which I call " mine "(withoutI

implying ownership !), the weather on the penulti-mate Sunday of January was a mixture. It followedwhat the sailor -men speak of as a dirty night, but itdeparted from pattern-for a time. On the Saturdayevening, ignoring the darkness and the rain, I haddeliberately done a 3o -mile journey, when two-thirdsof that distance would have carried me home. Onthe Sunday morning-I hate to say it !-the sun, lowin the heavens and shining on wet roads, was somethingof a nuisance, dazzling to the eyes in a mildly painfulmanner. Ore does not complain of sunshine in January,of all months, and it was really delightful to behold theliquid gold.

I picked up an old friend at lunch, and thereafterwe set forth for a village three miles away in order toobtain tea. As, however, the journey occupied twohours, it is obvious that we did not seek the shortestroute. In other words, we " made a ride of it." Wewere interested in noting the effect of the over -nightrain. The little rivers were brimming, their attendantwillows standing knee-deep (as it were) in the flood,and angry, tumultuous waters hurried across the field%and under the bridges. Here and there a new streamhad come into being, flinging itself downhill or over theroad, in a 'most reckless, irresponsible fashion, andmaking the mole of its brief life.

The morning dazzle had long since departed, and agrey sky reigned supreme. When we turned into thehitter, searching wind, life was not so easy, but therecame a lucid moment at sundown when the skymomentarily cleared and displayed a riot of colours inthe west, giving us also a glimpse of distant hills. Thehouse aimed at for tea turned us down owing to illness,and we went forward to the cottage which had providedour midday meal, there eating hot buttered toast andabsorbing many cups of tea in an atmosphere of warmthand joviality, and forgetting the ordeal through whichwe had passed.

Afterwards we lived again the strenuous life, battling,with a fierce cross -wind, which ultimately developedinto a head -wind, accompanied by cold rain. Despitedifficulties and discomforts-and remembering the joyof the morning sunshine-we wrote down the day as agood one. It was a day of acceptable adversity-a dayto recall with pleasure-and the process of jotting thefigure " 7o " in my diary (representative of my mileage)crystallised the delight of an experience in which dazzleand deep waters played very definite parts.. Of theultimate glory of the night sky of black velvet, prickedby a million brilliants, one can only say that it added afitting crown to a good day.

" It Never Rains . . ."THE recent experience of one of my cycling friends

seems to show that there is some truth in the oldtag that "it never rains but it pours "-as some of usknow from the incidence of punctures. This man keepsthree bicycles in commission. The front forks of onecollapsed the other day. Almost immediately after-wards a horse knocked over and trampled on a secondbicycle, necessitating extensive repairs. Up to themoment of going to press, the third machine is intactand in use, and it is to be hoped that the " rain " hasstopped. Two such incidents all at once, in these daysof scanty (and second -grade) repairing material, are atrifle unfortunate for a keen cyclist who, living on anisolated farm, must rely on bicycles for transport toand from business in an adjacent city.

THE CYCLIST 47

/X,e, 4',410=VarGli;,WZATO.MoM;Y WASYlle07.9

4.5nsFsuGj

Deaf EarsIT is well known that if you tell the man in the streetI. a thing often enough he will come to believe it.Hence the success of rot quack remedies for pains inthe back, bad legs, spots in front of the eyes, and soon and so forth. But when the man -6r woman-in the street does not hear what is said, or see what iswritten, where are you ? Just nowhere I We whotravel on wheels have had impressed on us for sometime past the urgency of proper inflation of tyres, but

A Fenland GemTHE Isle of Ely is one of those so-called islands-

one that just comes within the definition, becauseit was at one time surrounded by water. There aremany such inland islands in this country, relics of thedays when the Fens were not so well drained as theyare to -day. History tells us that owing to its position,surrounded by fens and marshes, it was once a placeof refuge. Ely is a somewhat little town, standing onone of the comparativelyhigh spots in Fenland andis often called the capital ofNorthern Cambridgeshire. Thecounty is not one that drawscyclists by the hundred to visitits charms, but in Ely at leastthere is a glorious attraction inits superlative cathedral.Although, perhaps, it is not con-sidered one of the finest of ourbeautiful churches, it is certainlyunique in its design. Its towerscan be seen from PeterboroughCathedral, 35 miles away, andfrom nearer view points it bulkson the skyline, appearing so hugethat one can imagine that onesees a mirage. The nave isNorman, and one of the out-standing features of the exterioris the fourteenth century Octa-gon. Many parts of the churchhave collapsed in its Soo yearsand have been rebuilt and re-stored, without, however,destroying its beauty. It wasthe collapse of the tower thatled to the building of the Oct-agon, a feature that is not to befound in any other Englishcathedral. It is said that it wasbuilt owing to an error of judg.ment on the part of the architect.He realised almost too late thatthe span was too great for astone dome and consequentlybe built it of oak. Aftersearching the country for eightoak trees, free from fault andbig enough for the task, theywere cut from Chicicsands inBedfordshire. Like Wells, Elyhas something to be said in itsfavour from a photographer'spoint of view. It can be seen andphotographed from a distancewithout a wide-angle lens, andwithout the necessity of tiltingthe camera. Although sleepythe town itself is far fromuninteresting, and is a real hay=of peace.

My Pointof View

WAYPARE.126200,.

those ,words oft wisdom have fallen onmuch stony ground and there is no harvestin certain directions.

One day recently, at a Shropshire haunt,I fell into conversation with two middle-aged ladies who were having tea, andwhen the meal was over I had a lock attheir bicycles. One was five years oldand in good condition; the other was atleast four times the age, and jn shockingcondition. But there was little to choosebetween the two machines so far as thestate of the tyres was concerned. Havingsecured the consent of the ladies, I got busy

with my pump (a real one I) and did theneedful. " There I " I said. " Now you'll beable to ride in comfort and with efficiency, andyou'll prolong the life of your tyres, which are in veryshort supply nowadays." The ladies thanked me-butI could not help wondering whether I had not been"wasting my sweetness on the desert air."

Quick DecisionsQNE of the most important things, as a cyciist, is to

know what to do in an emergency-and then

to do it. Two of us were traversing a narrow, and(as we thought) a deserted, lane, riding "all over theroad "-a policy suggested by the seclusion, anddictated by the broken surface. Suddenly, round abend, came two other cyclists, travelling in like manner.The total speed was considerable, and instant actionwas necessary if collisions were to b% avoided. As ithappened, all four cyclists did the right thing. Thetwo inner men of each party accelerated ; the two outermen reduced speed and each got in behind his com-panion. Thus nothing untoward occurred. But itwas an occasion for quick decision, and there was notime for mental fumbling. This is a worth -whilelesson which can be gathered up only in the hardschool of experience, where one learns to do the safething.

On another recent occasion two of us, emergingfrom a lane into a secondary road on which traffic wasnot expected, saw a hurrying motor -car approaching.There would probably have been time for us to crossover in front of the vehicle and take up our rightfulposition on the road, but instinct said " No 1 Stopand we both palled up. This was the safer plan,

" Some " DetourIWAS interested to read in my newspaper the other

day that General Eisenhower, on his way to thiscountry from North Africa (or thereabouts) called inat Washington and had an interview with PresidentRoosevelt. Evidently the Supreme Boss of the SecondFront is a man after my own heart, though my detoursare very " small potatoes " in comparison with his.As a cyclist, however, I am all for roundabout routesfrom one place to another.

JestAWAR correspondent in Italy reports that a local

cyclist threw a bomb at a lorry full of Germans,killing the lot. Perhaps, thereby, not improving thegeneral reputation of cyclists I

Notes of a HighwaymanBy LEONARD ELLIS

A Lakeland FraudFROM the low-lying country of the Fens we travel

swiftly to the highlands; of Cumberland, England's-lake country. Here we can see another feature, thistime a natural one, that is world famous. The LodoreFalls are perhaps as well known as any falls in England,and this is probably due to the publicity given to themby the poet Southey, who wrote a magnificent andthrilling poem extolling the dashing falls. The curious

fact remains, however, that LodoreFalls are something of a fraud. Itis true that when Lodore is in spateit is a wonderful sight, but this isonly after a heavy rainstorm. Atmost other times it is possible to sitin the middle of the watercourse, asI have done, and wonder where thefalls were. It must not be thought,however, that the scenery around isfraudulent, as the site of Lodore is ina really beautiful glen. The Lodorejokes are almost as famous as theLodore poem. It should not benecessary to say that the stream isthe Watendlath Beck, a stream thatruns into Derwentwater at thesouth-east ccrner.

Ely Cathedral.


SIR WILLIAM ROOTES, K.B.E., onRoad Problems --(Continuedfrom page 41.)

fore, more than -anyone else, rests a greatresponsibility-a responsibility fof bringingabout a new state of affairs to the benefit notonly of employment, but of the country asa whole. I am sure that Lord Leathers willnot let this opportunity pass, because it isan opportunity. We have alwayi been toldin pre-war days, that we cannot change it,that we cannot start again, thit this and thatcannot be done, but no Government hashad such an opportunity presented to itlike ours to -day, where they have expertplanning, where they have a world receptivefor new ideas, where they have a determinedcourage, where there will be a great change,and this country will gain in prosperity and,as an empire, will be able to hold its own inmatters of commerce.

" I also feel that the Government can becertain of one thing, and that is that, astime goes on, there will be a growing volumeof public opinion in this country that thecitizen should have as much freedoria as isreasonable for rebuilding our national effortand giving scope and initiative for enter-prises without which, to my mind, we cannotbecome competitive and successful.

" I hope that these few remarks which Ihave made at random will appeal to you all.You as Roadfarers must obviously be lookingforward to what is to come, and I feel at anytime that transport, whether rail or road,requires a greater volume of support, it willbe forthcoming."

Professor A. M. Low, in proposing thetoast of " The Visitors and the Press," accen-tuated the remarks of Sir William Rootes,but thought that there should be a move formore silence on the roads. In ' replying,

Mr. H. G. Wells said : I will do my aged best torespond to the very flattering reception theRoadfarers' Club has accorded me. NowadaysI am a Roadfarer in spirit rather than in fact.I don't get on the road very much ; gout(richly deserved, thank Heaven !) and apatriotic disinclination to use petrol (whichalso I can't get, anyhow) keep me in London.Such ways as I follow nowadays are sea -waysand air -ways. If I travel much in future, itwill, I hope, be by Brabazon No. t, for yourpresident, the Lord of Tara, is also no longera Roadfarer. Like all the rest of us here Iprofess nomadism: I am by habit and naturea nomad. I hated my ,.home is a child andrejoiced to leave it. I admit it was not amodel home. Mostly I lived in an under-ground kitchen, or in an attic that let in thewet, and I spent as much of my time aspossible in the streets of Bromley. Home,Sweet Home meant nothing to me. But do'esit mean much more to any of us Roadfarers ?Home, Sweet Home is a sentimentalist's dream'Suitable for singing abroad. As far abroadas we can get. Then nostalgia ceases to bea vice and becomes a pleasure. But peoplewho really want to live at home for goodand all-well, it seems to me that theproper penalty for them is to put them in aHome-for good and all.

All this talk that is being bandied about,about putting men back in the places towhich they belonged before the war, fills mewith piotesting doubts. Only the other dayI was publishing a letter from an admirableBritish soldier, in hospital in the MiddleEast, a Zulu namd Hlope. His one passionatedesire was that he should never be sent backto servitude and inferiority in South Africa,and I believe there are hundreds of thousandsof British soldiers who will be of the samemind. Back to the old round ? No fear !

They won't want to be put back. We haven'tfought this war to be pullback.

Never in all my life have I wanted to stayput. Directly bicycles became available forme I got one and went off on it. DirectlyI could get a car I got a car and went off init, driving dangerously, I admit, but anyhowgetting away. I believe you are all with'ineto -day in a unanimous detestation of beingrooted to the soil. 1 am a man, not a tree.

Here on my right hand I find Sir WilliamRootes, and I am happy to say he has beliedhis name and pulled himself up to join usRoadfarers. On comparing notes we find weboth belong to that great nation, that starupon the front of England, Kent, which stillto this day sustains the equestrian tradition,the Roadfaring traditions of Hengist andHorsa. Those two came to England by sea.Yes ! but they didn't call themselves seamen.They were riders, and they must have riddena long, long way before they reached Jutlandand jumped the narrow seas to Kent.

Well, you will be wanting to hear whatSir William has to tell you, so I will endthis little Hymn to Movement.

I have lived in a great variety of places, Ihave built several houses, but always I haveshaken thein off, given them away, thrownthem away, with infinite relief and the happyexpectation of new and refreshing experiences.

At present I am interned in a house uponRegent's Park. I can die very comfortablythere if need be, but I am just as willing formy ashes to enrich the soil of China or Peruor South Africa.

So let us move on to the next speaker.Move on, says the Greet Policeman. Get amove on. That, I take it, is what this Clubexists to assert, and which I have done mybest to underline.

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