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254 NEWNES PRACTICAL MECHANICS May, 1945

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PREPARE FOR PEACE -TIME COMPETITIONIn the more competitive days of peace, technical training will be a vital necessity to theEngineer who wishes to safeguard his position and make advancement. " ENGINEERINGOPPORTUNITIES " will show you how to secure this all-important .technical trainingquickly and easily in your spare time. This 100 -page book is full of valuable informationand explains the simplest way of preparing for recognised Examinations. Among thecourses described are :

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

Editor : F. J. CAMM

VOL. XII MAY, 1945 No. 140

Post-war TelevisionTHE Report of the Television Committee

appointed in 1943 to prepare plans forthe reinstatement and development of

the television service after the war has justbeen published. They were charged withthc duty of preparing a plan for the provisionof a service to the larger centres of populationwithin a reasonable period after the war, tosuggest schemes for research and developmentand to suggest what guidance should be givento manufacturers with a view especially to thedevelopment of the export trade.

In order to refresh the memory of ourreaders we remind them of the steps whichhad been taken or were under considerationat the outbreak of war to implement therecommendations made for the establishmentand development of a public television servicein the report of the first television committeeunder the chairmanship of the late LordSelsdon in 1935.

Two Rival SystemsTHE first public television service of high

definition in this or any other countrywas inaugurated at the B.B.C. TelevisionStation at Alexandra Palace in November,1936. The transmissions were at firstprovided during alternate weeks by tworival systems, Baird and Marconi-E.M.I., butin February, 5937, the Television AdvisoryCommittee came to the conclusion that theMarconi-E.M.I. was the better system, andthereafter that system alone was employed,'

The Alexandra Palace transmissions in-volved separate vision and sound signalsfrom two transmitters operating on frequenciesof 45 me./ sec. and 41.5 mc./sec. respectively.The vision trans`mitter emitted positive imagesas opposed to the negative image adopted bythe Americans and produced a peak radiatedpower of 17 kw, corresponding to the picturehighlights.

The sound transmitter followed conven-tional design and radiated a power of 3 kw.The transmitters delivered power to twoseparate aerial systems mounted one abovethe other giving a total height of some 6o6ft.above sea -level. The vision aerial wasmounted above the sound aerial.

The ratio between the vision and soundtransmissions, namely, 17 kw. and 3 kw.,proved in practice to be fairly satisfactory.The standards of picture transmission were45o lines, 5o frames interlaced, 'jgiving 25complete picture frames per second.

ScanningIN the normal process of scanning, the

picture to be transmitted is divided upinto a great many lines, each of which istraversed by the scanning apparatus. In

passing the scanner records the picturedetails encountered along each line, andconveys this to the receiver. In sequentialscanning each contiguous line is exploredprogressively in turn. The process ofinterlaced scanning, however, consists inscanning all odd lines first, subsequentlyreturning and scanning the even lines requiredto complete the picture frame. Althoughcomplicated, the interlacing system hasjustified itself, because the apparent flickerfrequency of the reproduced picture isdoubled, and hence the flicker renderedimperceptible without materially increasingthe technical difficulties of transmission.

Experience shows that reliable results fromthe A.P. transmissions were obtainable withina range of 35 miles, and even further in somecases of interference -free situations. The limitof range was determined by the deteriorationof the signal -noise ratio of the received signal.

By 1939 this service had reached a highstandard of entertainment value, but thenumber of television receivers in use wasonly about ao,000. Sets in those days costfrom f2o to -C75. The public, no doubt,considered that the restricted range of the trans-missions indicated that television was still inthe experimental stage, and perhaps thataccounts for the small number of receivers.

Research WorkT T was then decided to form a plan for a1 service on a semi -national scale -to bringtelevision within the reach of the majority ofthe densely populated areas of this country.The main difficulty apart from those of atechnical nature was finance, and the warcaused television to cease because the signalsfrom Alexandra Palace formed a useful D.F.signal for the enemy. Although in the earlystages of the war research work was plannedin several directions, the war made it impos-sible to maintain any organised research, andas a result little progress has been made inbroadcast television.

Radiolocation owes a great deal to pastresearch work on television, but war researchhas produced little information and nodiscovery of a fundamental character bearingdirectly on television.

The committee has reached the conclusionthat the right course in the present circum-stances is to reopen the television serviceon the basis of the ,l°5 line system rather than!to wait for the development of a new televisionsystem as the result of research. The reasonsinfluencing them in reaching this conclusionare :

The Alexandra Palace television service hadby September, 1939, reached a 'high state ofperfection, which with wartime research willbe improved. Many of the pre-war receivers

BY THE EDITOR

failed to do justice to the signals which weretransmitted and there are good reasons forthinking that with improved transmissionand better receivers the 1939 standard willsoon be surpassed.

A good deal of research and developmentas well as new studios and other buildingswill be required before a greatly improvedservice can be put into operation. Some yearswill have to elapse'', for obvious reasons, beforeany new service will be available to the public.The re-establishment of the new televisionservice, as soon as posSible after the war, isimportant, for it will prevent the dispersalof the highly specialised staffs who wereemployed on television in pre-war days. Theservice, it is thought, can be in operation within9 to 12 months of the release of the requisitestaff. There should be no avoidable delayif this country is to hold its own in the tele-vision field. Extension over a wide area of thetelevision service is essential if there is to bea full development of the television industry.

It would, however, obviously be un-justifiable to proceed with a rapid extensionof the old television system to the provincesif the intention was to discard it after a fewyears in favour of an entirely new one. TheCommittee thinks that the old system willcontinue to appeal to many people even aftera new system has been introduced. Thesame programme could, of course, be used

,for the two systems.

DefinitionTHEY think that television definition should

eventually be of the order of t,000 linesand that the introduction of colour andstereoscopic effects should be considered.In other words, television should endeavourto approach the cinema standard. It willbe necessary to secure the release of theAlexandra Palace from its present war uses ;it is far from ideal for television purposes,but a new site is at piesent out of the question.

Then the service should be extended tosix of the most populous centres in the pro-vinces. It is thought that a service couldbe established in the Birmingham area withina year of the re-establishment of the Londonservice.

Other points in the Report are : Thepossibility of the use of cinemas for dis-playing television programmes ; it is vitalthat the Postmaster- General should begranted the necessary powers to enforce thesuppression of electrical interference ; aresearch organisation to develop televisionshould be formed at the earliest possiblemoment ; a patent pool should be formed ;export of television sets should be encouraged ;there should be international standardisationof television.


Welded ShipsThe Advantages of Liberty Type Ships Compared with Vessels of Riveted Construction

THE information given in these noteshas been compiled by the WeldingDevelopment Department of the

Lincoln Electric Co., Ltd., Welwyn GardenCity, from American sources.

Release of this information has beenapproved by the U.S. Navy Department,U.S. Maritime Commission and the U.S.War Shipping Administration.

One of the most stirring stories of thewar describes the ability of welded ships towithstand the terrific explosions and frequentfire damage to which they were subjected byenemy action during the crucial years of 1942and 1943. Besides actual combat service,many of these vessels, under emergencyshipping conditions, experienced long voyagesthrough heavy seas in all kinds of adverseweather conditions.

Although a number of gallant seamen werelost during the height of Axis efforts to cutour vital supply lines, prominent navalauthorities agree that the saving of an untoldnumber of lives was undoubtedly due to thesound principles of ship construction madepossible by welded design.

Surviving Combat DamageSome of the most dramatic stories in marine

history have come from the logs of thefamous Liberty type ships. Although manyof these sturdy vessels have been blasted bytorpedoes, bombed from the air and rakedwith enemy shellfire, nearly all of them arestill on active duty.

Stern vie

In comparing these welded ships with thevessels of the riveted type, Admiral EmoryS. Land, chairman of the U.S. MaritimeCommission, says, " Every time a rivetedship goes into dock, you have a lot of repairsto do which you do not have in welded ships.You do not have openings in your hullswith dozens and dozens of leaks, nor do youhave to redrive rivets. Even if we havefractured plates, it is but a handful of leakscompared with the casualties in riveted shipsevery time they go in for voyage repairs-something that everybody seems to haveforgotten.

" In combat damage, comparing Libertyships and others, everything is in favour ofthe Liberty ships. A lot of them have broken

Ltosections, due to combat damage ; in

iberty ships, the percentage is entirely infavour of the Liberty, because the rivetedships are apt to go to the bottom when theyare bombed or mined or torpedoed. It istruly remarkable the salvage we have obtainedfrom these Liberty ships in combat damage.Never mind about the fractures or cracks-they get into port."

Two Remarkable Liberty ShipsThe Patrick Henry, first Liberty ship to

go into active service, is one of the scores ofvessels of this type which have substantiatedAdmiral Land's remarks

Launched in September, 1941, the PatrickHenry was subjected to numerous bombingsand torpedo attacks on such dangerous routes

as those to Murmansk andArchangel, and to Capetown andSuez. After two years of severeservice, during which the vesseltravelled some 80,000 miles andmoved more than 76,000 tonsof supplies . to Allied warfronts, an inspection of thePatrick Henry showed her to bein ' first-class condition andprompted , the War ShippingAdministration to hail herperformance as " even betterthan anticipated."

One of several Liberty shipsthat were torpedoed, but refusedto sink, was the Anne Hutchinson.Describing the incident in aproduction communiqué to thebuilders, Oregon ShipbuildingCorporation, Admiral Landsaid : " To you who built theS.S. Anne Hutchinson goescredit for having built a sturdy

ILiberty ship. She took twotorpedoes in her stride andrefused to sink. It was on herreturn trip when the firsttorpedo struck in number fourcargo hold. The explosionalmost lifted the ship out ofthe water ; it severed the lineshaft and practically tore outthe ship's bottom. J The vesselbroke in half and it was onlyafter being buffeted by stormsthat the after part sank. Theengine room bulkhead held andthe forward part of the vesselremained afloat. Later thesecond torpedo struck inthe starboard engine room in theway of the boiler. Threeseamen . were killed. This

o, an ail -welded prefabricated British -built tanker explosion completely destroyedjust before launching. the starboard boiler and shifted

the main engine from its foundation to feetto port. Still your vessel would not go down,she remained in an upright position and wastowed- into port. The survivors said thebuoyancy of the vessel after being sliced intwo parts was amazing. All of you whoworked on this ship can feel justly proudof her."

All -welded_ Oil TankerIncluded in the long list of 'the all -welded

oil tank ships with notable performances,was the motor ship Pennsylvania Sun, whichhas piled up a total of 506,000 miles. Thisvessel was torpedoed in 1942 and sufferedextensive damage to the hull, the super-structure being entirely gutted by fire.

The Sun Oil Company, operators of theship, told of this action in a recent letterwhich stated, " The vessel was torpedoedat the midship house on the port side ; theexplosion tore away the side shell platingand one wing bulkhead, and pierced the otherwing bulkhead, opening approximately seven ofthe cargo tanks to the sea. However, whenthe fire on the vessel was put out by theship's officers and a salvage crew, the crewreboarded and effected temporary repairswhich permitted the ship to proceed underits own power to dry dock at Chester,Pennsylvania, for the execution of damagerepairs. It was noteworthy that in mostcases plates would tear in half or would tearaway from a welded joint, the welds apparentlyshowing up stronger than the steel itself."

The reliability of welded hulls is empha-sised in another report from the War ShippingAdministration on the Robert E. Peary, whichsustained major damage on two occasions.

The report states, " In May, 1943, en-route to the United Kingdom, water wasfound in No. 3 compartment, due to fracturedshell plates ; damage was believed to becaused by depth charges, but this informationwas not confirmed. The vessel was dry-docked and repaired in the United Kingdom.In the December of 1943 the vessel wasinvolved in a collision outside Halifax, N.S.,and returned to Halifax for dry-docking andrepairs. Exclusive of her present voyage,this vessel has travelled approximately 42,246miles."

Over 2,..eoo Hulls in 40 MonthsShips such as these were produced at the

rate of more than 2,158 hulls in the relativelyshort period of about 40 months.

It was this record which led the U.S." Special Committee Investigating theNational Defence Programme," to reportthat, " The most material stleparture fromthe method of construction of the originalship was in the use of electrical welding insteadof riveting. The adoption of assemblyline methods and extensive prefabricating ofparts also made possible the constructionof a greater number of ships than had everbefore been contemplated.'

Further comment is found in a statementreleased by the U.S. War Production Boardwhich reads as follows : " Ugly Duckling(Liberty) type merchant ships were foundto be to per cent. to 15 per cent. stronger inconstruction and smoother in line than theships of 1919, which had' 900,000 rivetbumps." This, despite the fact that weldingused- less steel, 'resulting in ships of consider-ably lighter weight. " Welding saves 845,000rivetsl.hpd 1,790,000 rivet holes," continuedthe WPB statement.


DAMAGED WELDED. SHIPS STILL AFLOAT

When the stern of the "E. H. Blum "was damaged,it was cut away and forward section shown here wastowed to U.S. East Coast port for repairs. Salvage

made possible by rigid welded construction.

(Above) Crew of this disabled shipprevent fire from spreading by pouringwater on oil tank covers. Notewarped deck with weld seams stillintact. (U.S. Maritime Commissionphoto, courtesy The Lincoln ElectricCompany, Ltd.; Welwyn Garden

City.)

(Below) Dense column of black smokeshows where torpedo struck. Ship,was salvaged for future deliveries Ofvital cargoes. (Official U.S. Navyphoto, courtesy The Lincoln ElectricCompany, Ltd., Welwyn Garden

City.)

..11r

Although these all -welded ships have been severely damagedby torpedoes or fire, they were able to be towed to portto be repaired for future service. The illustrations are fromofficial U.S. Navy photographs, and show how all -weldedconstruction saves war scarred ships from becoming total

losses.

(Above) The gaping hole shown inthis view of an 18,000 ton tankerfailed to send her to the bottom.Sturdy welded construction preentedcriticaPdamage. (Official U.S. Navyphoto, courtesy of The LincolnElectric Company, Ltd., Welwyn

Garden City.)

(Below) Torpedoed merchant tankerstill afloat. (Official U.S. Navyphoto, courtesy The Lincoln ElectricCompany, Ltd., Welwyn Garden

City.)

Close-up of a torpedoed Liberty ship after sternsection had been damaged by enemy action atsea. Photo shows forward part of ship after itwas towed to port. (Official U.S. Navyphoto, courtesy The Lincoln Electric

Company, Ltd., Welwyn Gdrden City.)_ .


Hand -made Paper

The " beaterman " at the " engine "for cleansing the rags which aresubsequently to be pulped to produce the " stuff " for hand -madepaper production. (By courtesy of J. Barcham Green, Ltd., of Maidstone.)

THERE are some things in this present-dayworld of ours which have not in anyway been improved by the manifold

advancements in science and technology. Theviolin is one of these articles. Paper is another.Not, of course, in respect of`the latter com-modity, that the speed and convenience ofpaper -making has not been enormouslyenhanced, compared with the methods in usea century or more ago. Not, also, that themultifarious grades and varieties of paperwhich are normally available nowadays donot represent an almost fantastical advanceon the limited paper types of an earlier age.

In spite of all this, however, there remainsthe fact that the very highest, the mostenduring and the best grades of paper whichare made nowadays are still produced by thelaborious hand method which was currentin this country three and four centuries ago.It is, indeed, something of a paradox that thebest possible grade of paper, to say nothingof the most enduring variety of that com-modity, is precisely the material which hasbeen produced by the most primitive ofmethods.

Such is our present-day " hand -made "paper which is still being turned out regularlyin a few paper mills and which for quality,endurance and appearance excels all otherpaper varieties.

Naturally enough, hand -made paper cannotbe applied for modern commercial pressand magazine work. '1'In the first place, itwould 'be far too expensive for such employ-ments and, secondly, its " natural " unfilledsurface, however fine it may be, wouldscarcely give the detail of pictorial repro-duction which is rightly demanded by themodern reading public. Nevertheless, for allartistic works, for the production of pencilor watercolour drawings, for etchings and forthe printing of costly and valuable bookeditions, hand -made paper is unexcelled.

For important document work, also, hand-made paper is unsurpassed. So, also, is itfor the making of registers and ledgers and' similar volumes which have to stand up to agood deal of handling and inspection.

The finest, the strongest and the mostenduring (even under adverse conditions) oflaboratory filtering papers are all hand -made.In fact, a large proportion of the output of"hand -made mills goes to such scientificusages.

Money PaperThen again, there is the question of the

now universal " money paper." Bank -notesof all countries are printed on hand -made

The Modern Methods of an Age --old Industrypaper, not only in conse-quence of its strength andessential durability, butalso because watermarkdesigns of the most intricatecharacter can be incorporatedinto such papers with a viewto preventing the circulationof fraudulent notes.Currency or money paperis, therefore, an importantproduct of the Englishhand -made paper mill, andit is a significant fact thatin pre-war years Govern-ments the world overobtained their supplies ofmoney paper from just afew English mills.

Hand -made paperproduction is a difficultjob, calling for the highest

of manipulative skill. It is a relatively slowjob as well, for it takes about a couple of

production. There are no strikes, contentionsor disputes in this diminutive yet none theless important industry, for each workerinvolved in the paper production is not onlya key -man, but also, in some respects, atechnological artist, and he is treatedaccordingly.

It is not worth the labour and skill involvedin the production of hand -made paper tomanufacture such material from shoddy orinferior substances such as straw, woodfibre and wastepaper. For this reason alone,hand -made paper is invariably producedfrom the very best of raw materials, thesebeing the highest grade of cotton and linenrags. Sometimes, for very special purposes," hand -made may be produced from newlinen cuttings and pieces, but, usually, theaforesaid good -grade waste linen and cottonrags are employed for the making of the paper.

The rags are first carefully sorted bywomen and girls. Pins, buttons, blackthreads and all other undesirable articles areone by one picked out from the rags, which

latter are then cut up intoshreds.

Lifting a hand -made sheet of paper from the " post " or pileof alternate paper and felt sheets which have been built up bythe " coucher. ' (By courtesy of J. Barcham Green, Ltd.)

months for a sheet of hand -made paperto complete its various processes inthe paper mill, during which operationalcycle the paper is subjected to about ahundred separate handlings.

There exists an assembly of hand -madepaper workers which is named the " OriginalSociety of Paper Workers." This societycame into being about the beginning of thelast century, being formed to protect the old" hand -made " craftsmen from the speediermethods of the machine -made paper operativeswho were just then coming into activebeing.

The "Original Society"The modern skilled hand -made paper

producer is invariably a member of theOriginal Society." His apprenticeship has

lasted for seven years. He is a craftsman inthe real sense of that nowadays ill-used wordand, in his chosen trade, he is permitted adegree of individual freedom which is quiteunknown in modern industry. Members ofthe " Original Society " very frequentlybelong to different generations of the samefamily, father, son and grandson succeedingeach other in the trade.

It is, in many ways, a labour of love, or, atleast, a labour of art, this hand -made paper

"Breaking -in"After this preliminary

treatment, the rags are" broken -in " in revolving" breaking machine s,which are fitted withdrum washers serving todrain away the dirty waterfrom the shredded rags.Sometimes a little bleachliquor is added to thewashing water in order toheighten the whiteness ofthe rags, but in all suchcases the bleach is mostcarefully washed out ofthe material subsequentlyin order to prevent itsslow deterioration after-wards.

The washed and bleachedrags are then transferredto a beating engine which

Laboratory extraction apparatus utilising anextraction " thimble " of hand -made paper.

May, 1945

breaks down the shredded rags to pulp, inWhich condition it is known in the trade a's

stuff."From the beating engine the paper pulp

(" stuff ") flows into a reservOir-the " stuffchest "-which serves as a 6Otitaine'r for theavailable stock of pulp. From the stuff chestthe pulp flows over electro-magnets, whichserve to remove particles of iron from it,and also through special devices known as

sand traps," whose purpose it is to extractany flinty or siliceous grains from the material.Finally the pulp, or " stuff," is passed througha sieve or strainer just before it passes to thepaper -making vat or tub, in which containerit is prevented from settling by means of arevolving agitator blade or " hog."

Now comes the most difficult process inthe paper -making art, that is, the formationof the sheet of paper in a mould. Machine -made paper can be turned out nowadays bythe mile, but the size limit of a sheet ofhand -made paper is governed by the size ofthe mould which the vatman can convenientlyand efficiently handle.Forming the Sheet

The paper -making mould is simple enoughin construction. It consists of a frameworkof hard wood having anumber of side - to - sidewooden bars, each barbeing perforated with smallholes which serve for thepurpose of,sewing down tothe ',frame a sheet of finewire mesh. If a watermarkis required in the paper, thedesign of the mark is sewnin wire to the wire meshsecured to the frameworkof the mould.

Used in conjunction withthe mould is the paper -making " deckle." Thiscomprises merely a woodenframe-something like athin picture frame. Thisrests flat on the wiresurface of the mould, itspurpose being to form theedges of the sheet of paperand to keep the pulp fromflowing over the sides ofthe mould.

When forming a sheet ofpaper, the vatman simplyclaps the deckle on to themould, dips the two intothe vat of pulp, lifts the

NEWNES PRACTICAL MECHANICS

mould up and gives it apeculiar wave -like shakewhich serves to give regularalignment to the particlesof stuff " or paper pulplying on the wire meshof the Mould and so formsa thin layer or web ofinter -matted fibres, muchof the surplus waterdraining :r a p idly awaythrough the underlyingmesh of the mould.

The Vatman's " Shake "This is the first stage of

the paper -making art. Itis, naturally, the mostimportant stage, and,incidentally, it is an almostindescribably difficult stage.

It takes years of practiceto acquire the all-important" shake " of the vatman,and it is upon this funda-mental manual operation that the strengthand texture of the resulting paper depend.

No two vatmen have the same " shake."

A

A laboratory paper -testing machine for determining the strengthof paper. A fragment of paper is placed within the screw -downclamp and the right-hand wheel is turned, causing an upwardstretching of the paper, which ultimately bursts. The burstingstrain is recorded by a needle moving over the dial on the left-hand

side of the machine.

The work of the coucher. The newly -madesheet of paper being pressed downwards from

the mould on to a sheet of felt.

Consequently, if one vatman replaces another,even when dealing with the same paper pulp,a noticeable difference may appear in theresulting papers produced by the two vatmen,despite the fact that the two workers areequally skilled.

If a vatman allows himself to fall into anervous condition-if, indeed, his mind isworried by any affair-he frequently " loseshis shake. Before he can remedy mattersand again display his customary skill, hisworry must be relieved, otherwise the paper -forming process will suffer accordingly.

Hence it will be realised that a skilled andexperienced vatman is indispensable to ahand -Made paper mill and, for that reason,he is given the greatest of consideration.

The " Coucher "Across the upper end of the paper -making

vat there is a sort of wooden bridge. On tothis the vatman places his mould after he hasformed his paper sheet and removed thedeckle from the mould. He then slides themould across the bridge to his co-worker,who is termed a " toucher " (French :coucher, to lie down). This man takes themould with its formed sheet of paper, hetilts it somewhat to allow more surplus water

261

vatman forming a sheet of paper in the mould.(By courtesy of J. Barcham Green, Ltd.)

to drain away and then he inverts it facedownwards on to the surface of a pad of felt.

The coucher then, carefully lifts the mouldoff the felt, leaving the sheet of paper adheringto the latter.

He places another sheet of felt on to thesurface of the paper sheet and then passesthe empty mould across the bridge to thevatman. The latter has by this time formedanother sheet of paper in another mould andthis he then passes over to the coucher, whoagain lays the paper sheet on to the waitingfelt, covers the latter over with another feltsheet and again passes the empty mouldacross to the vatman. Thus the, process goeson for hours without serious interruption.

Gradually the coucher accumulates a pileof alternate sheets of new -formed paper andfelt pads. This is called a " post."

'When the post attains a standard height, itis squeezed in a heavy press. This removesall remaining water and, after removal fromthe press, the sheets are stripped away fromthe felts by an operative known as a " layer."

The layer then piles the sheets into "packs,"which packs are again pressed (this time forabout iz hours), after which the individualsheets are separated and hung up in a loft soas to dry out naturally.

WaterleafThe dried paper sheets-technically known

as " waterleaf "-are fragile and are, of course,quite unsuitable for writing or drawing on,although they have their uses for certaintypes of printing processes.

To be of service, the waterleaf has to besized, and this is effected by subjecting thematerial to the action of a pure gelatine size.At one time, the sizing used to be carried outindividually, sheet by sheet, but nowadaysthe sheets of waterleaf are placed between twoendless bands of fine felt which travel slowlythrough a vat of size (gelantine and water)and then through rollers which serve thedouble purpose of squeezing the requiredamount of size into the fibres of the paperand of squeezing away all surplus size fromthe surface of the material.

Great care has to be taken of the composi-tion of the size, and also of the purity of itsingredients, otherwise paper staining results.The size contains a little soap, and also somepure alum. If too much soap is added,the paper tends to become transparent,while if there is too great a proportion ofalum in the size it crystallises out in littleglistening specks in the surface of the paperafter drying.

The sized sheets of paper - are usuallystacked into low piles for about a day, beingcovered with felt the while in order to keepthem warm and, thereby, to prevent the sheetsfrom sticking together. The individual sheetsare then separated by women and girls,


Making

mechanical endurance.Some of the papers, par-ticularly the writing papers,are plate glazed, or hotpressed, to give them asmoother surface, but a gooddeal of the hand -made paperis marketed in the rough -surface condition.

There are quite a numberof varieties of hand -madepaper, apart from thedifferent surface types ofthis paper. Take , for,example, the exceedinglystrong, tough and enduringpaper which is often usedfor bank -note printing andother purposes. This is fre-quently made from oldyacht sails and from aircraftlinen. It is difficult toprepare a pulp ,from this

,Soxhelet," or chemical extraction filter " thimbles, material, but once therequisite degree of finenessfrom pure hand -made paper.

(By courtesy of Barchcon Green, Ltd.) has been obtained aftermany hours in the beating

and they are allowed to lie about individuallyin order to dry off the remaining water ormoisture.

DryingFinally, when all visible traces of moisture

have departed, the sheets are taken up tothe drying lofts. Here the paper sheetsmay be hung over hair ropes, or they may belaid upon scrupulously clean fine hessiansacking.

The temperature of this loft drying is veryimportant, for if the paper dries too quickly

The conditioning room. Hanging up the finishedhand -made paper to condition and matureunder the influence of controlled humidity and

temperature.

(owing to the presence of undue local heator, alternatively, of draughts) the paper willbe ruined.

The paper, after being stacked for a fewdays in loose piles to " mature " or condition,is then carefully examined by experiencedsorters, who divide the mass of material intothree classes-good, " retree," and " broken."

" Broken " paper is usually repulped." Retree " represents " seconds " quality.It is like the curate's egg, good in parts,and it has a commercial value. " Good "paper is, of course, the first-class materialwhich is turned out and guaranteed by thefirm.

Many grades of hand -made paper aresubsequently resized in a weaker gelatinesolution after drying to give them a greater

engine or pulp -making machine, the stuffbecomes so fine that it feels greasy to thetouch. Paper made from this base is semi-transparent, and if thisfeature is deemed undesir-able, a small admixture ofpure, white cotton rag hasto be made in order toconfer the requisite opacityto the finished paper.

Water PurityNaturally enough, in all

hand -made paper mills, thestrictest attention has to bepaid continually to thepurity of the water usedin the operations. Mostmills, therefore, make use oftheir own private springs,thereby ensuring a water ofa constant and knowncomposition.

The presence of iron inthe water brings aboutstaining, due to oxidationof the soluble iron mattersin the water. This oxidation may appear it by machinequickly, or,. on the other hand, it may, production lines.

Soxheletutilised in

in after years, produce on the paperthat peculiarly annoying brown spot -likemarking known as foxing." 'A perfectIypure hand -made paper will not give rise tothis trouble if it is preserved uncontaminated.It is only a paper which contains iron withinit or which, in some way, becomes contam-inated with iron which gradually developsunder damp conditions, this unsightly mani-festation of slow deterioration.

There is a prevailing impression thathand -made paper is costly material. To alarge extent, the notion is erroneous. Wherestrength, appearance and, above all, enduranceis desired, there is nothing to beat hand-made paper. Compare, for example, a bitof newsprint (news paper) which becomesyellow after a couple of weeks' exposure toair and sunlight, or again, compare a sheetof the brittle highly glazed " art paper "after a year or two's exposure-compare thesewith any modern product of a hand -made'paper mill, or, better still, perhaps, with thetough mellowed paper of an 18th, a 17th oreven a t6th century volume. Such a com-parison will at once reveal the merits of thehand -made variety of paper, a materialwhose production, strangely enough, seemsto have defied all efforts of modern scientificpaper -making technology to deal with

" thimbles. Cylinders of pure hand -made paper, aschemical laboratories for the chemical extraction of

numerous substances.

processes, and on, mass -

Imperial College: Centenary Celebrations, 1945

PRESUMINGthat the war in Europe will

by then have terminated, the ImperialCollege is planning to celebrate next autumnthe centenary of the Royal College ofChemistry, from whieh, through two of itsthree constituent colleges, it can trace descent.The third week in October is contemplated,and it is hoped that H.M. the King, asVisitor of the College, may find it possible tobe present. In connection with this centenarythe college has recently launched an appealfor funds which, by providing an endowment,will enable it to develop a corporate life morecomparable with that of colleges in the olderuniversities.

Royal CharterThe Imperial College of Science and

Technology, constituted by a Royal Charterdated July 8th, 1907, is a federation of threeconstituent colleges-the Royal College ofScience, the Royal School of Mines, and theCity and Guilds College (formerly theCentral, Technjcal College of the City andGuilds of London Institute) ; and these inturn Were related with earlier institutions fromwhicT a -aardingly, the Imperial College can

trace descent. The earliest of all, the RoyalCollege, of Chemistry, is' that of which thecentenary falls in this year. Its first presidentwas H.R.H. Prince Albert (later the PrinceConsort), who had' also opened (1851) theMuseum of Practical Geology in JermynStreet, with which de la Beche associated his" Government School of Mines and of ScienceApplied to the Arts." From this source,later, both the Royal School of Mines and theRoyal College of Science derived, and the nameof the Prince Consort is thus associated withtwo of the constituent colleges of to -day.

The Imperial College is a School of theUniversity of London. Subjects at presentavailable for study or as fields of researchinclude Biochemistry, Biology (Botany, Ento-mology and Zoology), Chemistry (Agricul-tural, Inorganic, Organic, Physical), Geology,Mathematics, Physics (including Astrophysicsand Technical Optics), Metallurgy, Mining(including Mining Geology and Oil Tech-nology), Engineering (Chemical, Civil, Electri-cal, Mechanical), Aeronautics. In them allthe instruction has by tradition a strong biastowards the practical and industrial applica-tions of science.


The Bailey BridAeExtracts from a Recent Broadcast Talk

by Donald C. Bailey

Al' the end of 5940, with France out of thewar, with many interruptions from theLuftwaffe, and when we in Britain

were expecting invasion, at that time my jobwas the designing of bridges. It still is myjob. But then-in 94o-bridge designingmight have seemed too optimistic. They werenot bridges to be used for the defence ofBritain. They were bridges I hoped wouldcarry our soldiers, tanks, guns and lorries onthe offensive-on the offensive over anyrivers and such -like obstacles which theymight chance to meet and wish to cross. Themilitary bridges then in existence were notstrong enough for the increased loads likelyto be brought into service. Until then wehad been able to stretch the capacity of ourequipment just enough to deal with suchtanks as the Matilda, which was just goinginto use, but no more straws could be addedto the camel's back without disaster.

The bitter lessons learnt from the GermanPanzer Divisions during their advance throughFrance had made it quite certain that biggerand better tanks were urgently necessary.Moreover, where there is a tank, there mustalso be a " tank transporter " to carry it onlong journeys.

But at this particular time-the end of1940-the designing of stronger bridges mighthave seemed unduly optimistic. It didn'tappear likely that there would lc,e any oppor-tunity in the immediate future for us to makeuse of bigger tanks and larger vehicles, or ofbridges to carry them, unless indeed theywere required in this country. Nevertheless,the order for a high capacity bridge had beenmade and designs had been put forward, andthese plans were being considerecI. It seemedmost essential that any scheme which was tobe adopted should not be limited to the loadsand smns required at that time. Theyshould be sufficiently adaptable to carry thebiggest vehicles which might come into service,and also remaining economical for carryingthe smaller ones-capable of taking biggerloads and not too cumbersome or costly forsmaller loads. It must also be easy to manu-facture in large quantities, and be capable oferection without too much technical knowledgeand training and, if possible, difficult toassemble incorrectly. They were the require-ments for this all-purpose army bridge.

eiccli.afr a Bulky h

Prefabricated Gir-der SectionsI'd had in mind,

for some time, the ideaof using completeprefabricated sectionsof girder, which couldbe erected side by sideor one on top ofanother to formcomplete girders ofgreatly varyingstrength. Thisseemed to have someadvantages over otherproposals, and so Ispent a good deal ofmy leisure for someweeks in developingthe design to a suffici-ently advanced stagebefore I put it forward.By early in January,1941, the main featuresof the project had beenworked out to putbefore the Ministryof Supply TechnicalAuthorities.

L.

A Bailey bridge erected over the Escaut canal by "RoyalEngineers, whoare here seen strengthening the original damaged pillars with girders,

and fixing shuttering ready for concreting.

With the scheme becoming an official one,help became available from the staff of theExperimental Bridging Establishment andfrom commercial firms and technical bodies,whose members included famous scientistsand engineers, such as the designer of theSydney Harbour Bridge.

Eventually about croft. of bridge girderswere made up by a local firm from a cheaperquality of steel, for we wanted to carry outdestruction tests to settle one or two hotlydebated points in connection with this ratherunusual type of construction. But we wereright. These triumphantly vindicated ourtheories, and at last the great day arrivedwhen we were to stage a demonstration beforethe War Office-demonstrating the buildingand launching of a complete 7oft. long bridge.We had only just got the girders and, of course,all sorts of minor misfortunes occurred,which prevented any prior assembly. It wasonly after a hectic all-night session by ourworkshops that it was possible for the Royal

c a gap iu a road bridgc in Italy.

Engineers, who were to erect the bridge, toget a little practice in on the very morning ofthe day on which the great men from theWar Office were due to arrive. They were tosee the bridge -building demonstration atnoon, but were unavoidably delayed.

At two o'clock the officer in charge of theerection party ordered, " In double time formbridge." He blew his whistle and they wereoff. Eventually the bridge was completedand launched across the gap, and a lorryrumbled across a Bailey Bridge for the firsttime. We looked at our watches-we hadnot dared to do so before. It was 2.36. The7oft. bridge had been completed in 36 minutes.

Yes, those sappers had been marvellous,as so many others have been since, and thatlorry was to be the forerunner of thousandsof others in all theatres of war in whichBritish, Dominion and U.S. troops arefighting. Since then thousands of tons ofBailey Bridge parts have been manufacturedby every conceivable type of contractor, fromsmall garages up to the largest steel worksin the country. Needless to say, the tremen-dous production did not go through withouthaving to overcome many difficulties, someof which only became apparent when theoutput was stepped up to a maximum. Theresponsibility of solving many of thesedifficulties fell to the Inspection Departmentof the Ministry of Supply, and they, togetherwith the Department that deals with theorganisation for supply of materials,'have donea fine job.

i,aoo-ft. Bridge in BurmaThe finest job of all, however, has been done

by the soldiers in the actual field of battle.These men have erected hundreds of thesebridges, of all sizes, under sometimes themost appalling conditions-in Tunisia, inItaly, in France, in Belgium, in Holland, inBurma, and, we hope, now in Germany, andshortly in Japan. Some of their feats, likethe I,2ooft. long bridge over the RiverChindwin in Burma, and a somewhat similarone over the Sangro River in Italy, were realachievements.


Dairy EnAineermHow Machines of Various Kinds Help in the Production and Supply of Our Everyday Milk

HOW many people stop to think howgreat a part is played by the engineerin the production and supply of good,

clean milk ? As a food it is of the greatestvalue, provided it is pure and free fromharmful germs. Therefore the milk, andeverything that it comes in contact with,must be scrupulously clean.

A few hours spent with a good dairymanwill not be wasted, so, after he has deliveredhis van load we will go with him back to thedairy. This dairyman values his good name,so his van is kept clean, and all the bottles

By C. D. WHITE

seen end on, with a back pressure valve andcock fitted.

To the right is the bunker, which is enclosedand the fuel put in from outside.

Washing RoomGoing to the washing room (Fig. 2) the

first thing seen is the low stool -like arrange-ment, which is used for the rinsing andscalding of large milk cans and other utensilswhich are too large to handle in the wash tank.You will notice it is connected to the waterand the steam supply pipes, a valve to each

Fuel

Bunker

Fig. it.-Interior of the boiler house.

are stacked in metal crates. Take a look atthese crates ;. they can be stacked to quite agood height without danger of falling over,because the top corners are fitted with a lugwhich fit snugly in the bottom corners of theother crate. It is almost an impossibility topush a stack of crates over.

Arriving at the dairy the bottles are alltaken from the crates and examined at thesame time ; some will be thrown away, mostlybecause they have got snipped around theneck. A bottle which is in this condition isdangerous, and many a dairy worker hasreceived a bad cut from a bottle with ajagged edge, also, when placed on the revolvingbrush of the washer the broken neck willshear most of the bristles from off the brush.That means added expense. More bottleswill, perhaps, be placed at one side becausethey contain dirt or sour milk. These willhave to be put in a bath of extra strong solventbefore going to the regular washing tank.

Boiler HouseOn entering the dairy buildings we see at

once that the dairyman is modern as well ascareful. His boiler house, shown in Fig. r,is equipped with a good boiler of the cross -tube type, is of ample size and well fitted up ;this in itself is an engineering job. The ownerknows that plenty of steam is of primeimportance if he has to. have clean utensilsand bottles. To the left of the boiler is shownthe water supply tank, connected to the mainsand provided with a ball -tap with valve. Theinjector is shown side on above the tank, sothat it can be seen ; generally, they would be

being provided, but both cannot be turnedat the same time. After being washed outwith hot water containing solvent these largeutensils are placed on the stool and given agood scalding and rinsing before being sentback to the farm.

Next to the stool is the washing tank corn-

plete with bottle -washing machine at the topright-hand side. This washer is of the multi -brush type, that is, it has one power -drivencentre brush as well as a number of steadybrushes spaced around this revolving brush.These machines are driven by turbine workedby steam from the boiler, or connected to anelectric motor. The tank proper can besupplied from the mains with water which isheated up with steam, a certain amount ofsolvent being used during washing. Let usnow watch the washing of the bottles whichhave been soaking while the water is gettinghot. There is very little noise during theheating of the water, and in keeping with hisother equipment the owner has had a silentheater fitted ; this small fitting keeps downthe noise and makes greater use of the steam.The bottle is taken from the tank, placed onthe fast revolving brush, and held there fora few seconds, the inside being thus given agood scouring. The operator then releasesthe bottle and quickly moves a swivel brushover the bottom, and while this is being donethe outside is cleaned by the steady brushespreviously mentioned. The whole of thisoperation takes only a few seconds, and it issurprising how quickly two girls can getthrough a van load of bottles. After washingthe bottles are placed on the rinser, which canbe seen to the right of and a little lower thanthe wash tank. There are various kinds ofrinsers ; some have only one jet which comesinto play when the bottle is placed in position,the flow of water stopping when the bottle isremoved. The type shown in Fig. 2 will holda standard crate, the crate being placed onthe tray and the bottles placed neck down inthe crate. When the crate is filled the wateris turned on and series of spaced jets spraywater up the inside of each bottle. The wateris then turned off and the bottles quicklydrain, all waste water runs into _the pipebelow the wash tank.

As the bottle -filled 'crates are removed fromthe rinser they are placed in the steel cabinetseen in the far corner of the washing room..

When a sufficient number of crates have beenplaced in the cabinet, the door is closed andmade tight by the locking handles. Steam isturned on' and left for some time, and after

Fig. 2.-The washing room.

May, 1945

turning the steam off, the whole is left tocool down. It would not be safe to open thedoor too early after shutting off steam, owingto the danger of cracking a lot of bottles. Theaction of the steam in the cabinet is tosterilise the bottles, thus killing all harmfulgerms, and at the same time getting rid ofany milk film which may have been in oron them.

You will notice on the far wall a water tapfor swilling, as well as a steam pipe to whicharmoured hose can be fitted if required.This is very handy, as a bucket of water canbe boiled any time when wanted.

The DairyThe crates along with the bottles are now

removed to the cold room, seen in Fig. 3.These are mostly of the automatic type, thatis, if the temperature drops below a pre-determined point the plant starts up on itsown and brings the temperature back torequirements. You will see over the door anelectric lamp, and this in many cases servesa dual purpose. If anyone is working insidethe cold room they must have light, so theswitches are placed inside, these same switchesare connected to the outside light which isred, so when the lights inside are in use theoutside light lets everyone know that someoneis inside the room. Also, in many cases, thered light comes into operation when thetemperature falls and the plant through somecause does not start up.

The fresh milk has arrived from the nearbyfarm which is also fitted up with steam tosterilise all the drinking and other utensilsused by the cattle, as well as the milkingmachine parts. The milk is poured fromlarge cans into the milk tank shown on theright near the back of the dairy (Fig. 3).From this tank it is pumped up over the topof the cooler, at the same time passing througha very fine sieve, although it has already beensieved at the farm. The milk flows down overthe outside of the cooler, which is corrugated,the inside being in the form of tubes after thepattern of a gridiron. Cold water from themains, brine, or in some cases cold air fromthe refrigerating plant, is passed throughthese tubes, and the corrugated form presentsa larger area than a flat surface, and alsohelps the milk to spread over all the surface.Great care must be taken of these coolers ; ifdamaged they may leak and whatever waspassing through the inside would leak out andmix with the milk.

Filling PlantFlowing from the bottom of the cooler, the

now very cold milk enters the tank of? thehand -filling arrangement seen in front of andbelow the level of the cooler. This particularfiller has four outlets, as shown, these outletsconsisting of tubes which go well down intothe bottles. On each tube is a metal discwith a deep centrepiece which is a good fit,but will slide up or down the tubes. If oneof these discs is lifted far enough you willsee that the tube is drilled through, theseholes being the outlets for the milk. Whenin use the action of putting the empty bottlein position lifts the disc and allows the milkto fill into the bottle ; as one bottle is fillingothers arc being put on or taken off. A goodworker can fill bottles with remarkable speedand the waste of milk is very small.

As a general rule, while one operator isfilling, another is sealing or capping. Metalcaps are used in some of the large concerns,but the average dairyman uses cardboarddiscs, which are inserted tightly in the neckof the bottle. Various methods are in use forthis ; some dairies use hard wood or metalplugs with which to press the caps home,others use a hand capper. This is a smallmachine worked on the principle of an auto-matic pistol ; it has a magazine which holds


a large number of cardboard discs. The noseof the machine is put in the neck of the bottle,care being taken to keep it straight with thebottle, the left hand steadying while the righthand presses the grip smartly down. A capis thus ejected and will be found tightlypressed into the bottle neck. These machinesare quick and efficient in action.

The filled bottles, having all been crated,are now moved back into the cold store untilrequired. As much labour as possible is cutout, even to moving crates inside the dairy.Trolleys, as seen in Fig. 3, are used, thesesmall trucks being made to fit the crates, and

jl

iii

265

ating the laws of centrifugal action causes theseparated cream to flow from one outlet, andthe skimmed milk from the other.

On the wall can be seen the switches whichcontrol the pump and' the separator, also asteam pipe with which water can he boiled forcleaning down, and also pumping through thepipes. The end of the steam pipe is made tofit an armoured hose, by means of which livesteam can be used to scald all the equipment.

The foregoing description applies to anyordinary, medium dairy, from which good,clean milk can be obtained. The milk is notGrade A, pasteurised nor sterilised! Large

is

W.rn,n9 c vh

0711171:o

P,"

I

Fig. 3.-Interior of a small modern dairy.

the wheels are arranged so that they can bemoved in confined places.

Near the front right-hand corner of Fig. 3is seen a small machine called a separator.This machine, electrically driven, by incorpor-

concerns work much more automatic, beingalmost continuous in their action.

Most modern dairies are fitted out instainless steel, although the use of heavilytinned equipment is quite permissible.

otes and NewsCoal Mining Machine

AT the present juncture in the history ofour country and of the world the rapid

and plentiful production of coal is absolutelyessential. Therefore any invention whichattains this result," if it can speedily be putinto operation, will be materially useful.

An inventor has set himself the task ofcontriving an improved method of coalmining. He asserts that generally twomethods of mining are known. In the firstcase, the Goal face is cut by a machine overa given length in such a manner as to weakenit and render it suitable for breaking downby the use of explosives or equivalent dis-ruptive means.

According to the second method, there isemployed a machine which cuts the coal in sucha way that it breaks down as fast as it is cut.Machines for carrying out this second methodare designed to make multiple cuts in the coalsimultaneously in different planes. Forthis purpose, cutters are used which operatewith a sawing or abrasive action. One of thesecuts, commonly called the shearing cut, ismade in a plane practically parallel with thecoal face.

The new device has for its object animproved means of cutting coal, so that it isbroken down as fast as it is cut and has theeffect of reducing the number of cuts.

The machine comprises a wedge -likesplitting head and only one endless cutter

which moves bodily with, but in advance of,the head. This makes a vertical incision (orshearing cut) in the coal, into which incisionthe head enters and splits the coal from theseam. And the leading part of the head islocated within the circuit of the cutter chain,so as to enter the incision behind the latter.

Shield for WeldersAN improved shield for the protection of

the eyes of the operator in electric arcwelding is the subject of an application to theBritish Patent Office. At present, the inventorremarks, these shields are usually providedwith an aperture in which is fitted a tintedglass or other suitable medium. This permitsthe worker to see the weld in operation. Inpractice, however, he adds, it is often difficultto see properly the position of the joint untilthe att has been struck.

The object of the new shield is to overcomethis disadvantage, so that the operator canhave an unrestricted view of the work untilthe arc is struck. Then a semi -transparentaperture in the shield simultaneously andautomatically closes to protect the eyes ofthe operator.

The characteristic feature of the new shieldis the semi -transparent screen mounted inthe shield adapted, as mentioned above,,,simultaneously and automatically to closeupon the striking of the arc by the operator.When the arc is broken, the screen automatic-ally opens.


AFTER the trials of the A.R.S. Experi-mental Rocket No. 4, no further liquid -fuelled types were constructed for

free flight, that is, not until 1939.The Experimental Rocket No. 3 was never

actually fired because of charging difficulties.Similarly, Experimental Rocket No. 5 -was notprepared for test, due in this particular caseto the results of earlier proving trials whichhad brought out severe failings in the design.

Since the building of these types, onlyground trials of liquid -fuelled rocket pro-pulsion units have been made, althoughcomplete powder rockets have been developedfor stability trials and tests of alightingmechanism, for the purpose of which, free -flight firings are obviously essential.

The more current experimentation of theAmerican Rocket Society comprises what isundoubtedly the most exhaustive technical

Air Infer

FuelWhirl

To PressureConstriction t`_ Gauge

Collar

WV'4/4 'N40144.c I Affp,

s.'s. \\.\\*

k.,..11111111

'N\\\

Rocket PropulsionThe American Rocket Society Rocket Motors on Test

By K. W. GATLAND(Continued from page 224, April issue)

mencement of operation each is suppliedunder fully 700 lb. per sq. in. This pressure issubsequently regulated, at full operation, to200 lb. per sq. in., and 16o lb. per sq. in., forthe fuel and water respectively.

The Truax Motor on TestThe complete unit, which was first tested at

Annapolis, Md., in December, 1937, had, forrecording, simply a beam balance. Becauseof the necessity of having the operator withinsome I5ft. of the combustion unit-forreason of safety-the complete set-up wasgiven a hydrostatic test up to tpoo lb. per sq.in. The motor and testing scale on the one side,and the fuel tank, water tank, air compressorwith containing tank (oxygen was not employedduring the initial trials), ignition gear, etc.,and operator on the other, were divided bya steel sheet.

Annular WaterCoolant Orifice

Water Infer

Fuel Inlet

Mixing Fuel CooledIgnition PlugChamber Nozzle 'Throat'

Fig. 22.-Sectional diagram of the Truax, fuel and water-cooled motor (5937).

development yet conducted outside thesecrecy of the Government laboratories.

In view of the technical significance of thiswork, it is perhaps desirable to go into thevarious designs and test procedures a littlemore fully than in the previous discussions.

The Truax Rocket MotorAmong the most successful types developed

by the Society to date is the waterfuel-cooled constant -volume motor (Fig. 22),designed by R. C. Truax.

The motor, designed to employ liquidoxygen, with petrol as fuel, was built almostentirely of nickel steel. Its chief attributeis in the unique cooling system, which com-bines a fuel circulation in a double wallednozzle " throat," with direct water injectioninto the efflux stream. This latter process iseffected through an annular slot formed intothe inside of the nozzle throat." The fuelis introduced at high pressure, and has its inletthrough the nozzle coolant jacket. From this,a fuel feeder line connects the nozzle jacketto a small pre -mixing chamber at the motor" head " ; the fuel entering at the side.Just prior to injection, the fuel is " atomised"by its forced passage through a small centri-fugal whirl fitted within the feed line. Theoxygen; which enters the same pre -mixingchamber directly from the motor " head," isthus homogeneously mixed with the fuelprior to entering the combustion chamber,Both the -fuel and water are forced to themotor tinder air pressure ; and at the corn -

The testing sequence was as followsAir is first supplied to the feeding lines,the ignition circuit cut in, and with the fueland water tanks fully pressurised at 700 lb.,the inlet valves operated. Air for com-bustion was then introduced at a slowly develop-ing pressure ; but unfortunately, in the initialtest, the motor refused entirely to respond.

A second attempt was immediately made,using the same functioning sequence, thesole difference being that the motor and fuelsupply lines were first raised in temperatureto red heat by oxy-acetylene flames. The fuel

CombustionChamber

To PressureGauge

system was again pressurised and air suppliedin slowly increasing quantity until the attain-ment of the required combustion proportion.On this occasion, the motor did fire, but inno way so effectively as had been hoped ; itssound emanated a motor -cycle engine-aloud continuous popping. However, withslight adjustment of the supply valves, themotor was at length made to function with asteady roar, but only for a few seconds beforereverting to its previous irregularity.

In view of these failings, the motor wasstripped down in a search for possible fault.Consideration showed that it might bethe case that the fuel supply had been affectedby the momentary pressure built up duringthe intermittent explosion periods, andthe constriction collar in the mixing chamberwas replaced by a smaller one, the intentionbeing to cause a greater pressure prior toignition. When put to further test, however,the motor did not even function.

In the next test, the restriction collar wasremoved entirely. The motor was again setup, and, after pre -heating the chamber, thefuel and air supply were once more cut in..Within a few seconds of adjustment, the motorfinally burst into life, but first only with thesame popping noise as had resulted earlier.Slowly the supply pressure was modulated,and then, suddenly, at a certain minuteadjustment, there came at last a loud, smoothroar; the sound indicative Of continuouscombustion. Almost immediately it becamenecessary to- operate the nozzle coolantsystem because of the rapid rise of tempera-ture which accompanied proper combustion.The water coolant device proved highlyeffective, cooling the motor instantly, and insubsequent trials the inlet was left slightlyopen.

Test ResultsAt the commencement of proper function,

the combustion pressure rose to 5o lb., andby effecting a gradual increase of the inputpressure-at the same time due care beingtaken to maintain the correct propellantratio-a pressure of 150 lb. per sq. in. wasfinally achieved.

Had oxygen been employed, instead of airas the " supporting " medium, it wasconsidered that the motor would quiteeasily have reached the designed chamberpressure of 300 lb. per sq. in. As it was, theinlet ports were too small to allow the airto build up sufficiently.

Fue/ Feed LinesCoolant Jacket

Fuelinlet

Pre -MixingChamber II

OxygenInlet

Fig. 23.-Sectional diagram of the Truaxfuel -cooled rocket motor (1938).

May, 1945

Several further firing runs were made'later in which, by an interchange of valves,even greater steadiness of control and }Aimingwas achieved. It is indeed unfortunate thatthe testing apparatus employed in theseparticular experiments was not more elaborate.There were, for instance, no facilities fordetermining such necessary characteristicsas the constant thrust factor or the amountof fuel consumed, and, therefore, the thermalefficiency. However, R. C. Truax-whoconducted the tests-reporting in Astronautics,April, 1938, pp. 9-11, made the followinggeneral observations, which, for our purposes,are in many ways as conclusive as the recordedfigure : " The matter of determining the properfuel mixture caused no concern ; the motorwould not run on an improper mixture.While the rocket motor was in full operationwithout water, there was neither smoke norflame issuing from the nozzle mouth. Thisprobably indicates excellent combustion andcomplete expansion. In fact, with the jetat full power an observer put his hand abouta foot and a half from the nozzle, and so

Ignition PlugOxygen Inlet


the British Interplanetary Society in July,1938.

The Wyld Rocket MotorAs with the motors previciusly described,

the point of significance in the Wyld regenera-tive motor (Fig. 24) is its unique coolingsystem. Again, petrol is used, with oxygen,as propellant.

With reference to the diagram : the fuelenters the motor at the double -walled nozzle,flowing round the combustion chamber,through the jacket " manifold," and is intro-duced, for combustion, at the motor " head."The oxygen is fed from a radial injector andenters from just above the fuel inlets, whichinject from radial holes at the sides. By thisarrangement, the fuel acts to cool both thenozzle and chamber, and, conversely, tovaporise the fuel by pre -heating, with aresultant improvement in combustive effici-ency. The complete motor weighs only 21b.

The Wyld Motor Under TestThe motor was tested on December loth

Combustion ChamberLiner

Fuel Cooled NozzleAssembly

Oxygen Injector Coolant Jacket

Fuel Inlet

V

Fuel InletFig. 24.-Sectional diagram of the Wyld self -cooled tubular regenerative motor (1938).

little heat remained unconverted that he wasable to hold it there (though with considerableeffort) without injury."

There is no doubt in the success of thecooling system. The amount of water con-sumed during the testing was about half thatof the fuel, but a reduced quantity wouldundoubtedly serve to cool the nozzle withlittle effect on the operating effciency.

As already mentioned, the fuel consumptionwas not directly recorded, but it has beenestimated that a total of about to gallons wasused to run the motor, intermittently and atVarying powers, for six or seven hours oftesting.

The Truax Fuel -cooled Rocket MotorA further Truax motor (Fig. 23), developed

early in 1938, featured a fuel -cooled combus-tion chamber and nozzle, with reverse fuelinjection.

As can be seen from the diagram, thecomponent layout is extremely simple and noelaborate " contouring " of the chamberand nozzle firing faces is involved. Dis-tinctions in the design are complete fuelcooling, and the provision of a propellantpremixing system at the nozzle " throat."

The design is such that the fuel entersfrom the side, near the motor " head,"circulating through the coolant jacket down tothe nozzle " mouth " prior to entering thepre -mixing chamber at the nozzle " throat "through feed lines. Small centrifugal whirlsfitted in the lines " atomise " the fuel priorto its injection. The oxygen enters thepre -mixer from the side, where both propellantcomponents are well mixed, prior to theirinjection into the combustion chamber-towards the motor " head "-through smallbore holes. A small ignition plug, fitted inthe chamber wall, serves to initiate combus-tion.

The fuel -cooled Truax motor- was shownin England when the designer visited Londonand delivered a lecture to an assembly of

1938, the recording apparatus being theAmerican Rocket Society Proving StandNo. 2.

Fuses, along with gunpowder looselypacked into the nozzle, were used for ignition.When fired, the gunpowder caused theexhaust to appear first as a large yellow flame,which immediately shortened into a " spear "of blue as the liquid propellant caught.At the same time, the reactive thrust rose to90 lb., which figure remained steady on therecording dial for 13.5 seconds, until theliquid oxygen became exhausted in thesupply tank.

Upon examination the motor showed nosign of defect, apart from slight meltingand erosion at the chamber " head " and

267

liner, which had occurred about an inch fromthe injector ports.

Empirical Performance DataThe performance figures of the Wyld

regenerative motor, derived from provingstand test, as from the period of efficientcombustion, are as follow : Maximumreaction,' 911b. ; alCohol feed, o.o841b., sec.;oxygen feed, o.341b. /sec. ; tank pressure,25o1b./sq. in. ; chamber pressure, 23o1b./sq.in. ; maximum exhaust velocity, 6,87oft.,/sec. ;maximum thermal efficiency, approximately4o per cent. ; and jet energy, 31o,000ft./lb.sec. ; or 565 h.p.

Further trials of the same motor were madein August, 1941, when the American RocketSociety experimental committee conductedthree exacting firings at their Midvale, N.J.,proving grounds.

In the first firing, the motor functioned for21.1 seconds, consuming during that time.about x21b. of propellant. The jet appearedas a violet flame approximately 3ft. in length ;the motor operating with a deep roar inter-spersed by sharp detonations which occurredat intervals of about five seconds. Theseregular explosions caused considerable vibra-tions, which, as well as shaking the provingstand, were actually felt by those taking partin the test. The phenomena which werein attendance throughout the three testingruns, caused no hurt to the motor.

The second test was concluded withsimilar results as the first, .though the firingduration was bettered at 23 seconds.

The final firing was by far the mostsatisfactory, lasting for a period of 45seconds, and, despite the use of -a leanerpropellant mixture, the motor recorded amaximum thrust of 13516.

The average thrust for the three firings wasapproximately 1251b., while the tank andcombustion chamber pressures were 25olbs.

One further point of interest arising fromthe trials was that, due to a misfire in theinitiation of one of the firings, unignitedpropellant ejecting from the nozzle developeda thrust of almost solb. on its own account.

These figures are among the most favourableever recorded by the American Rocket Society.Coupled with the fact that the motorfunctioned almost without damage, this datashows clearly the increased reliability obtain-able in the development of liquid -cooledrocket propulsion units. A similar, thoughadmittedly less ambitious motor, it will beremembered, was produced a number ofyears earlier by the German engineer, Dr.Eugen Sanger.

A Mosquito of Coastal Command being loaded up with rockets while final adjustments aremade to the machine preparatory to taking off.


In of InterestAuti-roll Ship Wings

AN invention to prevent the inconvenienceoccasioned by the rolling of a ship is

not a new idea. Some years ago a ladyof title devised a berth which, whatever theangle of the vessel, always remained level.An anti -rolling arrangement is the aim of aninvention which has recently been submittedto the Patent Office of this country.

This consists of wings formed of steelplates ro feet in length, t foot broad, and

inch thick., One of the so feet edges isriveted to the inside of the so feet lengthof steel angles.

The steel angles are riveted to the topsides of the ship, the after ends being6 inches above the water line, above whichthe fore ends are 18 inches.

Such an arrangement should mitigate roll-ing and make for the convenience of: thepassengers and crew. 4

Storm proofLighterTN these days when matches are in short-I- supply, the lighter acts as an effectivelocum tenens-sometimes. To improve thismethod of getting a light is the object ofa current invention. The originator has real-ised that a flame's breath of life is oxygen.He provides a lighter in which special meansis adopted to feed oxygen to the flame, and toguard against easy extinguishing, so that heclaims that his lighter is practically windand Itormproof.

This lighter has the usual casing and ahollow cylindrical wick, both open at thetop. The characteristic feature is that thereare openings in opposite sides of the casingand of the wick. These permit a current ofair to pass through them into the wick.

The same inventor has contrived alsoa lighter in which means are provided againstloss of combustion mixture or liquid vapours,or to retard such loss. There are a cap anda removable bottom section furnished withabsorbent lining, preferably composed of anumber of layers of thin textile materialpressed one upon the other. This is designed.to absorb the fuel vapours accumulating inthe casing and cap, and bottom section, whilethe device is closed.

Surgical Appliance

THEnormal method of treating a burst

blood vessel is the application of a tout-niquet, which is a bandage or pad tightlytwisted on the artery. A newly designedfirst -aid appliance for arresting bleeding froma wound in the arm or leg consists of twosteel arms hinged together so that they canbe adjusted with respect to each other. Thearms co-operate around the arm or leg toexert pressure by virtue of their springinessupon the artery above the wound.

Resilience Without Rubber

THE present shortage of rubber makes awheel which needs no rubber, and is

yet resilient, undoubtedly a desideratum. Anew invention consists of a wheel without thecustomary pneumatic tyre.

This wheel comprises an outer rim, anda number of quarter -elliptical leaf springs,each rigidly secured by oneend tangentiallyto the inside of the outer rim. And thereare links pivotally connected by one end tothe free ends of the leaf springs. The otherends of the links are pivotally connected tothe inner portion of the wheel.

By "Dynamo"Trailer Brake -control

WHEN a motor vehicle has a trailer, ifthe brakes of the tractor and trailer

are not applied fairly equally, there is adanger of vigorous snatching of the towingcoupling, resulting in the loss of directionalcontrol. For example, this may occur during

The inforrnation on this page is speciallysupplied to " Practical Mechanics " byMessrs. Hughes & Young, Patent Agents, or7, 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."

sudden application of the brakes while acurve is being rounded.

With a view to obviate this risk, an in-ventor has contrived special brake controlmechanism. His device includes a brake -actuating member for the tractor, and anotherfor the trailer. There are also a driver'sbrake -controlled member, and a differentialmechanism interconnecting the three mem-bers. And a spring limits the displacementof the trailer -brake actuating member untilthat member has been displaced by the pre-determined resistance which has been builtup.

Lubricating Track Rails

CURVING rails require constant lubri-cation. Otherwise they are easily subject

to wear and tear, and may produce unearthlyshrieks.

Light Bricks

YET another process relating to buildinghas made its advent. The inventor

asserts that during the last few decades, afterthe erection of the steel or Ferro -concreteframework of a building, the outer and partywalls have been filled in with ordinary claybricks, limestone, hollow bricks of terracotta or silica, etc. It is realised that there isno longer any need for the filling material topossess any great resistance to compression.Outer and party walls have only their ownweight to support. Their sole function isto serve as protecting screens against theelements and atmospheric changes. It ;sparticularly desirable that the material usedshould be light in order to reduce to a mini-mum the load on the framework. The outerwall surfaces at least must be unaffected byatmospheric conditions.

The object of the new process is to pro-duce a light material suitable for outer andparty walls for steel -framed or ferro-concretebuildings to be made from cheap and plen-tiful materials, which need not themselvesbe light.

MOULDED UNDER PRESSUREThe bricks consist only of limestone and

Portland cement. The limestone is crushedinto grains. These are graded by siftingthem through three sieves of successivelyfiner meshes. Grains of more than aboutfour millimetres across and grains, of lessthan about three millimetres across areselected. The granules of intermediate sizes

A " sheepfoot" roller for pummelling the ground, being pulled by a bulldozer. These .

specially formed rollers will be largely used after the war for housing clearance and roadconstruction.

There has been devised a new apparatusfor applying lubricant to the sides of trackrails. According to this invention, the lubri-cant container is vertical, and is attached tothe rail. It has a superimposed weightedpiston, so placed that the instantaneous rapidflexing of the rail augments the effect ofgravity upon the piston to expel the contentsof the container.

are eliminated, so as to form small cavitieswithin the mass. The larger selected granulesare mixed with about twice the amount ofthe smaller selected ones. This combinationis then mixed with Portland cement andwater. The resulting mixture is mouldedunder pressure equalling that of the atmo-spheric.


NEW SERIES

The Annals of Electricity -4Tapping the Lightning's Energy. The Electrical Experiments of Benjamin Franklin

BENJAMINFRANKLIN led a full life.

By basic occupation a printer anda stationer, he became an editor, a

newspaper owner, and a celebrated author,besides raising himself to the status of a sortof alderman or town councillor.

Climbing still higher, he found fame as adiplomatist, and, in this high capacity, hefound an exalted position in the councils of thethen embryo American nation, putting the sealof national eminence and distinction on hiscareer by becoming one of the signatories ofthe famous American Declaration of Inde-pendence of July 4th, 1776, the formalinstrument by means of which, as a resultof the inherent and constitutional stupidityof George III and his ministers, Englandlost for ever her formerly hard-won andlucrative colonies on the American mainland.

But besides all this work on the part ofFranklin, he Also found time not only tointerest himself in the then very immaturescience of electrics, but, also, by dint of hisown individual experiments therein, to becomea world authority on electricity.

Franklin, too, dabbled in mechanics (tosay nothing of theology, metaphysics andkindred other subjects). He also invented asmokeless stove, went in for constructingprinting gadgets, and experimented a little inscientific chemistry.

Franklin's father was an Englishman. Hehailed from the little village of Ecton inNorthamptonshire, and had been a dyer bytrade. But when, about 1685, he emigratedto the New World, he blossomed out as a soap -boiler.

Fondness for BooksBenjamin Franklin was the fifteenth child

of the English Franklin. He was horn atBoston on January 17th, 1706. Being a brightlad, he was sent to a local grammar schoolat the age of eight, with the intention of his,ultimately entering the ministry.! However,the parent Franklin, in view of his large family,found himself unable to educate Benjaminto such a calling. Instead, seeing the lad'sfondness for books, he put him to the printer'strade in the office of his elder brother James,who was at that time a flourishing printer.

Side by side with his learning the printingbuSiness, Benjamin devoted much time toother studies, including science, languages,and mathematics. Ultimately, at the age of17, he left his brother and went to New Yorkin search of a fresh job. Soon afterwardshe removed to Philadelphia and eventuallyestablished himself in that town as theeditor, author, printer and proprietor ofthe Pennsylvania Gazette. Previous to thissuccess, he had made a voyage to England,working in London as a printer for abouteighteen months.

His settlement as a master printer andnewspaper proprietor at Philadelphia broughtsuccess, and a certain amount of independenceto Franklin. He now began to fill variouspublic offices, a phase of his career which,as we have already noticed, led him to posi-tions of very high statesmanship in hiscountry.

With such facets of Franklin's career wecannot, of course, deal in this article. Instead,we must now betake ourselVes to Leyden,in Holland, in which town, the' year being1746, an electrical investigator' named Petervan Musschenbroek had noticed that electrifiedbodies always lose their electricity*whenexposed to the atmosphere. Musschenbroek

wanted ;to electrify a quantity of water, and,in order to prevent its " de -electrification,"he placed the water in a glass jar having artordinary iron nail standing within it, thefunction of the nail being to conduct theelectricity to the water from the frictionalmachine.

An associated experimenter named Cuneusheld the glass jar with its nail in contact with

Benjamin Franklin in his later years.

the conductor of the elecuical machine, andwhen, still holding the jar in one hand, hetouched the nail with the other, he received aviolent shock.

Peter Musschenbroek then repeated theexperiment. He got an even worse shock,

Franklin's kite experiment, by means of whichhe collected static charges from the clouds

during a thunderstorm.

so much so that he wrote to the effect thatnot for the imperial crown of France wouldhe expose himself a second time to a similarshock.

The Leyden jarThus came into being the famous " Leyden

Jar," a device, which as all experimentersknow, consists of a glass jar having an innerand an outer coating of tin foil reaching towithin about'a couple of inches from the top.The jar is corked, and through the cork passesa brass rod surmounted with a brass ball andmaking contact at its lower end with theinner tin foil lining of the jar by meansof a small length of flexible chain.

The Leyden jar is a simple storage device forfrictional electric charges. It represents theworld's first electric accumulator.

For a considerable time, the action of theLeyden jar remained a complete mystery.The best minds in Europe could think of nosuitable explanation for this.

In far -away Philadelphia, Benjamin Franklinhad become postmaster of the town. He hadestablished a public library and had alsofounded an " American PhilosophicalSociety " for the discussion of scientific,literary, and other learned affairs.

Up to this time Franklin knew nothingabout electricity. He had become mechanicallyinclined, and had invented his smokelessstove, which had attained success in America,and had even reached the distinction of beingpirated in England.

At one of the meetings of the PhilosophicalSociety, Franklin came into contact witha certain Dr. Spence, a Scotsman, who, itseems, had some practical acquaintance withthe modus operandi of the electrical experimentsof the day. He performed some experimentsfor Franklin, with, of course, the anticipatedresult of firing Franklin's imagination. Fromthis stage onwards Franklin became aconfirmed electrical " fan," devoting muchof his spare time to experiments andconjectures concerning the new science of" electrics."

Peter Collinson, a London F.R.S , appearsto have sent Franklin full particulars of theContinental experiments with the Leydenjar. Franklin at once repeated the jarexperiments. He found that an insulatedball, after contact with the inner coating ofthe jar, was repelled by the outer coating,and vice versa. He made an experiment inwhich he suspended a light cork ball withinthe jar between two wires which were,respectively, connected with the inner andouter tinfoil coatings of the jar. Betweenthese two wires the cork ball (having firstreceived a charge from the outer tinfoilcoating of the jar) oscillated until theapparatus had completely lost all its electricity.

Electrical LawBasing his theory cn these experimcnts,

Franklin offered the first explanation of thejar's action, and, simultaneously, he announceda more general electrical law to the effect thatwhen two oppositely charged conductorswhich are separated by an insulator arebrought near to each other they_will attracteach other.'

Franklin, therefore, was the first man toshow that positive attracts negative.

On. one of Franklin's famous statues inAmerica is inscribed the statement

" He snatched the lightning from Heaven,and the sceptre from tyrants."


The latter portionof the legendobviously refers tothe famous Declara-tion of Inde-pendence, in whichFranklin had someclose concern.; theformer portion ofthe phrase com-memorating Fran-klin's epoch-makinglightning experi-ments, and hisdemonstration ofthe similarity of thelightning flash tothe electric spark.

For years variousexperimenters hadessayed opinions tothe effect thatelectric sparks andlightning are bothmanifestations ofone and the samething. Nobody,however, had everattempted to proyesuch a theory, and,indeed, manyactively disbelievedin it. In fact, whenFranklin first

The " bush ess end" of communicated toa modern lightning rod. the stately Royal

Society, in London,an account of his lightning experiments, andhis theory concerning the identical nature oflightning and the electric spark the membersof that august body saw fit to laugh withmuch gusto when the paper was read. Itmust be remarked, however, that, in afteryears, the Royal Society, repenting of itserror, made Franklin an honorary member,and also awarded him its most cherishedhonour-the celebrated " Copley " medal-which is only given for scientific eminenceof the very highest order.

Experiments on LightningFranklin began his lightning experiments.

in the year 1752. At first, he had proposedto have a wire conductor attached to a churchsteeple which was to be built, but therehappened to be some delay in the erectionof the steeple so that Franklin conceived theidea of flying a kite in a thunderstorm, whichexperiment was duly carried out. The kiteconsisted of a silk handerkerchicf stretchedon a cedarwood frame. The frame carrieda vertical copper Wire, which made contactwith the long length of kite string to thelower end of which was attached a large ironkey.

To the key, also, was attached a length ofstout silk ribbon, this ribbon being held bythe person in charge of the kite.

When the thundercloud approached, thepointed wire of the kite attracted an electricalcharge which then ran down the kite stringafter the latter had been thoroughly wettedby the rain. It reached the iron key, but wasunable to' pass along the silk ribbon becausethe latter was held under the shelter of ashed by the operator, and so retained in afairly dry condition.

By means of this simple apparatus Franklinwas able to draw off large amounts of electricityfrom the iron key at the lower end of the kitestring. He produced large electric sparksand performed all the recognised electricalexperiments of the time.

In reality, however, this experiment ofFranklin's was a highly dangerous one. Theonly factor which saved him and his assistantsfrom instant electrocution was tile inadequateconductivity of the wetted siring.

Having thus, with certainty, established theidentity of the electric spark with the lightning

flash, Franklin reasoned that the destructiveenergy of the lightning might be neutralised(at least, in part) by securing conductors tothe highest places of buildings and by runninga metallic wire or ribbon from those conductorsto a plate buried in the earth. Just as a portionof the lightning's energy ran down the kitestring, so, argued Franklin, it ought to proceedto earth safely and non-destructively via themetallic conductor attached to the buildingin question.

The First Lightning ConductorThus came into practical being the world's

first lightning conductors. The first permanent lightning conductor was erectedon the house of a German clergyman, andshortly afterwards many were erected inAmerica.

A Russian professor named Richmann,living in St. Petersburg (now Leningrad), hadan insulated lightning conductor runningdown into his laboratory for the purpose ofstudying atmospheric electricity. Unfor-tunately, the device ended in a tragedy. Duringa severe storm occurring in August, 1753,Richmann entered his laboratory and ap-proached the lower end of the lightning rodwhich had been carefully insulated. As hedid so, a large ball of fire was observed byan assistant to jump outwards from the rod

The first battery, consisting of a box of Leydenjars connected together for the generation of a

large spark.

and to enter Richmann's body, flinging himinstantly to the floor and killing him on thespot.

St. Elmo's FireBenjamin Franklin, quite apart from his

zeal for national and political causes, foundhimself almost world famous in consequenceof his lightning rods and his electrical experi-ments. He was able to throw fresh light onold mysteries. For instance, he showed thatthe former highly mysterious " St. Elmo'sfire," an electrical luminescence which wasoften noticed playing around the tall, pointedmasts of sea -going vessels, was merely anelectrical phenomenon, the mast acting inthe capacity of a lightning rod.

Franklin's success with his lightning con-ductors led to his retirement from activebusiness. It was, however, only a nominalretirement, for his subsequent social, diplo-matic and Government work fully occupiedthe remainder of his days, even, indeed, to theeventual exclusion of all further scientificexperimentation.

It should be noted that Franklin recom-mended that all lightning rods should bepointed at their upper ends, since he foundby experiment that pointed conductors werebetter collectors of electricity than wereblunted ones.

In opposition to Franklin, a number ofauthorities in England and on the Continentannounced that pointed conductors wereactually dangerous since they " solicited thelightning," whereas a blunted conductor, suchas one with a metal ball fixed on its end,does not attract lightning but, at the same

time, draws off the electric energy from theclouds in a perfectly safe and harmless manner.

For a time, the matter was allowed to becomean affair of very great dispute in scientificcircles, and when, in 1772, the EnglishGovernment requested the Royal Society todecide which was the best type of lightningconductor to erect over gunpowder factoriesand magazines, the dispute took upon itselfa decidedly acrimonious character, somemembers of the Royal Society insisting ontheir recommendation of pointed conductors,the others warmly praising the superiority ofblunted or knobbed " conductors. Needlessto say, Franklin himself was not to be consultedon the subject, he being then what we wouldnow term an " enemy subject," or, possibly,in the eyes of the Georgian Government, a" war criminal " !

" Points versus Knobs"The Royal Society could not decide on the

matter of " points versus knobs." At last,the reigning monarch, George III, hadknobbed lightning conductors put up overhis palace, by way of setting an examplewhich he hoped would be imitated. Theoccasion gave rise to the following epigram :

While you, great George, for knowledgehunt,

And sharp conductors change for blunt,The Nation's out of joint ;

Franklin a wiser course pursues,And all your thunder useless views,

By keeping to the point !

It is seldom remembered that it wasBenjamin Franklin who first introduced intouse thg terms positive and negative to expressthe condition of bodies containing more orless than their normal amount of electricity.In our days, of course, in the light of theelectron theory of matter and electricity, theprecise conception of positive and negativehas been revolutionised.

One of the questions which occurred toFranklin's mind was this : Is the electricitywhich is manifested by the rubbing of a silkrag on a glass tube created by the friction ofthe experiment or is it derived from someoutside source ?.

Franklin tackled the problem by standingon a large cake of resin, thus effectivelyinsulating himself from the ground. He then'electrically excited the glass tube by rubbing'

The first- eletirical accumulator-a Leyden jar..The example illustrated was made during

Franklin's lifetime.

May, 1945

it with his bare hand. Afterwards, he drewoff its electricity into his own body.

Now, Franklin realised that if he haddrawn off the electricity from a similar tubewhich had been excited by another personhe would have become strongly electrified.As it was, however, he did not becomeelectrified.

In view of this fact, he reasoned that therewas no change in the sum total of electricitywhich he communicated to the tube byfriction and that which he drew off from it.Hence his body did not show any signs ofelectrification.

He tested this view by separately insulatingtwo individuals. One of these rubbed thetube ; the Qther drew off electricity from it.In this instance, both individuals becameelectrified. But when the two persons, stillinsulated from the ground, touched each other,all signs of electrification instantly vanished,a small electric spark passing between them.


" Franklinism"It was upon experiments such as these that

Franklin based his theory of (frictional)electricity. It was called the " Frankliniantheory," and was even, indeed, sometimesdubbed " Franklinism," as if it had con-stituted some kind of religious philosophy.

Franklin's theory had it that every naturalbody or thing contained within it some definitequantity of a subtle " electric fluid." Whenbodies or substances are equally suppliedwith this " fluid " or energy -principle, nosigns of its existence are evident. But hen,for instance, a glass tube is rubbed, thenatural distribution of the " fluid " betweentwo substances is disturbed. The glass tubereceives more than its share, the excess beingderived from the hand or the pad whichrubs the tube.

Considering the times in which Franklinlived and worked, the theory of electricity

271

which he evolved was remarkably accurate.Substitute the idea of " electron -deficiency "for Franklin's " disturbance of electric fluidand you have the germ of our modern theoryof electrification.

But, of course, Franklin must have been anall-round genius, and it is just these all-roundgeniuses who have a trick of getting to gripswith Truth years (and sometimes centuries)before the latter becomes apparent to otherpeople.

There is no doubt that Franklin was a mostvaluable pioneer in the realms of electricity.In later life, however, national fame overtookhim. He became a founder -statesman ofAmerica, and his electrical essays took aback seat.

He died at Philadelphia on April 17th,179o, advanced in age and honoured by all,friends and political enemies alike, theworld over.

High-power Short-circuit TestingTesting Technique, Special Equipment, and Layout of a Testing Station

By S. STATON

APART from the question of economics,which is of prime importance to allengineers, the electrical supply engin-

eer is mainly concerned with the reliabilityof supply to the consumer. The British gridis a fine example of engineers' efforts in thisdirection.

During the past five years of war, reliabilityand maintenance of supply have become morevital than ever ; whilst demands on the supplyindustry have increased a hundredfold.In spite of all these increased demands, andthe difficulties of war, the electrical supplyindustry has maintained its high standard ofefficiency and reliability, which is indeed atribute to the British Engineer, and theequipment he has produced for the industry.

There are, of course, many different piecesof equipment which go to make up a powersupply system,and the supply engineer, whenhe purchases this equipment requires proofthat they are capable of meeting all servicerequirements and conditions. It is the dutyof the manufacturing engineer to supply thisproof, and common practice is for the manu-facturing engineer to carry out an agreedseries of comprehensive type tests on theparticular equipment he manufactures. Thetests are conducted in the presence of thecustomer's representative if this can bearranged ; failing this, the tests are carriedout by the manufacturing engineer andcertificates of the test results are forwardedto the customer, in this case the supplyengineer.

In this article it is proposed to set out highpower. short-circuit testing technique asapplied to circuit breakers.

The special equipment and layout of atesting station will be described and thecharacteristics of the testing circuit withmethods of varying its severity discussed.Finally, the assessment of performance fromoscillograph records will be explained.

Service Requirements of CircuitBreakersIt has been stated that the supply engineer

requires proof that the equipment he ispurchasing is capable of meeting all servicerequirements, and in order to obtain thisproof agreed tests are carried out.

Before a clear idea can be obtained of thesignificance of the various agreed tests forcircuit breakers, as set out by the BritishStandards Specifications' 116/37, it will be

necessary to consider what may be requiredof a circuit breaker in service.

Normal DutiesFig. 1 shows a circuit breaker connected

between an alternator and transmissionline. Under normal conditions, the duty ofthe circuit breaker is to make the line " live "at the required time by switching on powerfrom the alternator. Secondly, to make theline " dead " by; opening and interruptingthe power flow from the alternanir. Thecircuit breaker must therefore be capable of" making " !, and ." breaking " the peakload current at the rated service voltage of theline at any time so required.

Abnormal DutiesShort Circuit Develops on "Live" Line.-

Consider now what happens if the circuitbreaker is closed with the line " live," and

quite possible that the short circuit of theline occurs whilst the line is " dead," thecircuit breaker thus being open. This shortcircuit, or fault, will not be made manifestuntil the line is made " live," by the closingof the circuit breaker ; thus the circuit breakerwill be closed on to a short circuited line.

To clear this latter condition is generallyworse than the former as will be seen byconsidering the sequence of events step bystep.

At some point along the transmission line,which the circuit breaker controls, the shortcircuit occurs ; this, of course, is unknown,as the line is " dead," or de -energised. Itwill be understood by the reader that thereare many lines which are not in use for thefull 24 hours per day. When the appointedtime arrives for the line to be made live,"the station control engineer closes theparticular circuit breaker concerned by

0

Ca he raror

0

Circuit BreekePoint OfSnort Circuit

Fig. r.-Circuit breaker connected between generator and transmission line:

a short circuit occurs at the point " X " alongthe line. The current supplied by the alter-nator immediately rises to a peak value, andthen gradually decreases to a final steadyvalue, as indicated in the curve Fig. 2. Thevalue anis peak current is governed by thereactance of the line, and any synchronousplant between the alternator and point ofshort circuit. It may rise to many times thevalue of the full load current.

Obviously, the alternator must be clearedof the fault ; and the circuit breaker is calledupon to break the circuit, and interrupt thisabnormal short circuit current, without anydamage to its contacts, frame, or mechanism,etc.

There must be no danger of fire or explosiondue to the current arc igniting the oil in thecircuit breaker tank and forming gas.

Circuit Breaker Closes on to " Dead " Linewhich is Short Circuited.-It is, of course,

energising its closing coil from the controlpanel in the control room. The closing coiloperates the closing mechanism of thecircuit breaker, thus bringing its contactstogether. Immediately the contacts touchtogether the short circuit is established, andagain the current supplied by the alternatorattains a peak value. The circuit breaker has,therefore, to " make " this peak value ofcurrent.

Tripping MechanismThe short circuit current sets up an

electro-magnetic force amounting to severaltons, which tends to hold the contacts andprevent them from closing fully. Considerablemechanical forces are set up on the contactcarrying bar, and this has to be capable ofwithstanding such forces. The electro-magnetic force opposing the final closing ofthe circuit breaker very often delays the

272closing to such an extent that the shortCircuit current has had time to operate therelays which operate the tripping mechaniSinof the circuit breaker, thus tripping thebreaker before it is fully; closed. As notbeing fully closed the comfireSSion springswhich are arranged to compress when thebreaker is closed are not fully compressed,and therefore they do not accelerate theopening of the breaker as would be the caseif they were fully compressed. The openingof the breaker is therefore slowed, and thishas a very marked effect on its ability to clearthe current arc.

Short Time Carrying Capacity.-There areseveral systems of protection in present usewhich may require a circuit breaker to remainclosed on a fault, or short circuit, until it hasbeen cleared at some other point along theline. The circuit breaker remaining closedhas therefore to be capable of carrying theshort circuit current for the time requiredwithout any damage to itself.

A A Vo. mat

coatiru,rent

NEWNES PRACTICAL MECHANICS May, 1945

symmetrical breaking capacity, and not lessthan too per cent. of 'rated making capaeity.

(5) Break-3'-break-3'-break, at notless than rOo per cent. of rated symmetricalbreaking capacity.

The 3' in between [the various tests arethree -minute intervals. In tests (t), (2) and (3),which are " breaking " tests, the breakingcurrent may be plus or minus zo per cent.of the specified test value.

In tests (4) and (5) it is to be noted that thecurrent must be not less than too per cent.

Voltage and Power FactorIn an A.C.. system the current passes

through zero twice in every cycle. Obviouslythis instant of zero current is the best timeto interrupt an A.C. arc.

Interruption can only take place if therate of rise of dielectric strength of the oilbetween the contacts is greater than therate of rise of voltage across them.

This voltage is termed " Recovery Voltage."In service, the recovery voltage dependson where the short circuit occurs relative tothe power station.

At remote points it may reach too percent., whilst at points close to the station it

1111111111111111RIIVII111111111111

Short Circuit Current

- rime in Seconds

Fig. 2.-Short circuit characteristic of an alternator.

It is not proposed to describe any systemon which the above conditions may occur,but the reader may, if he desires, read ofsuch schemes in any text -book on protection." Group Feeder " schemes furnish aboutthe best example.

-Standard TestsTo ensure that a circuit breaker will meet

the above service requirements standard testsare carried out as follows :

(I) Break Test.-Short circuit current ispassed through the closed circuit breakerunder test which is tripped to interrupt 'thecurrent.

(2) Make -Break Test.-The circuit breakeris closed on to a'short circuit, and then trippedto .interrupt the current.

(3) Make Test.-The circuit breaker isclosed on to a short circuit, but is not trippedto interrupt the current, the tripping beingdone by the station circuit breaker.

(4) Short Time Test.-Short circuit currentis passed through the circuit breaker undertest for intervals of one second and fiveseconds.

It has been proved by experience thatalthough a circuit breaker may successfullyinterrupt the maximum K.V.A. stated on itsrating plate, it may fail to interrupt a fault oflower magnitude.

A series of tests are carried out to provethe breaker on this matter, as follows :

(t) Break-3'-break-3'-break, at io.per cent.' raid symmetrical breaking capacity.

(2) Break-3,'-break-3'-break, at 30per cent. rated symmetrical breaking capacity.

(3) Break-3'-break-3'-break, at 6oper cent. rated symmetrical breaking capacity.

(4) Break -3 '-make break -3 '-makebreak, at not less than too per cent. of rated

may be about the 70 per cent. to 8o per cent.mark. The value of the recovery voltage alsodepends upon the system power factor.

Fig. 3 shows how the recovery voltagevaries with power factor.

The testing plant must be capable ofreproducing the severe conditions met inservice, and at present the following conditionsare specified :

(t) For circuit breakers up to 500 m.v.a. therecovery voltage must not .be less than 95 percent. of the rated service voltage.

(2) For circuit breakers of larger breakingcapacities than 500 m.v.a. the recoveryvoltage must be as near to too per cent. ofthe rated service voltage as possible.

A variation is allowed in some casesdepending on the particular test plant'employed.

Since the systempower factor has animportant bearing onthe severity of thetest, as seen in Fig. 3,it is laid down that dur-ing testing operationsthe limits of powerfactor are o.t5 forcircuit b;eakers up to500 m.v.a. and 0.30for circuit breakers ofany higher rating.

A.C. and D.C.ComponentFig. 2 illustrates

the characteristic ofa short circuitedalternator.

It will be noticedthat the current waveis displaced from the

zero line during the first few cycles, afterwhich it becomes symmetrical again.

This displacement depends upon theinstant at which the short circuit occurs ;the displacement being a maximum when theshort circuit occurs at the instant of zerovoltage.

This unsymmetrical current wave may beanalysed into two components.

(s) A direct current component as indicatedby the line A and B (Fig. 2).

(2) An alternating component indicatedby the difference between the lines ABand CD. The R.M.S. of the A.C.component is taken to be the same as analturnating current wave of constantamplitude, whose maximum value is half thedistance between CD and EF. The directcurrent component has a bearing on therecovery voltage as will be seen from a studyof the curves in Fig. 3. In the first three" Break " symmetrical tests and the fourth" Break "-" Make Break "-" Make Break"rest, the breaking current in any one of the

must not include a direct currentcomponent of more than zo per cent. of theA.G. component at the instant of contactseparation.

In the fifth " Break " asymmetrical test,the direct component must not be less than5o per cent, of the A.C. component at theinstant of contact separation.

Distress of Circuit BreakerIt is important that a circuit breaker

must be capable of " making," " carrying "and " breaking " its full load rated currentafter each or all of the above -mentionedtests.

If the circuit breaker becomes a wreckafter clearing a short circuit, it has obviouslyfailed its tests and would be no use forservice requirements.

Conditions are laid down in B.S.S. 116/37relating to the general behaviour and factorof distress of a circuit breaker under testduty.

These matters which include smoke andoil emission, condition of contacts, and anymaintenance of the breaker between testduties must be included in the test reports.

In the next article the special equipmentand layout of a testing station will be described.

(To be continued)

Workshop Calculations,Tables and Formula

By F. J. GAMIN6/. By Post 6/6

From George Newnes, Ltd., Tower House,Southampton Street, London, W.C.2

voltage

Max

Vo/tage

0

Curren

Power Factor = r Power FaCte,, SC 0

Fig. 3.-Diagrams indiiating variat'on re recovery voltage with powerfactor.._


HAVING now had practice in makingup the straight and curved rails, thenext step is to make points. The

majority may draw the line here, but iftackled in a methodical manner it will notpresent any great difficulty.

Fig. 13 shows the points for a right-handturn, and this type can be fined into anyformation, either in the curved or straightportion, and I will later show differentmethods of adapting it to various tracklayouts.

Of course, we shall also need the oppositehand and if the diagram, size, etc., arereversed the construction will be exactly thesame, so I will keep to the right-hand turnfor the stmt.

First lay out the diagram Fig. 13 (whichis to scale) tc. full size on a piece of woodor stiff cardboard, and mark in the rails andthe sleepers as shown.

F.-51 F-6-1 pi

Fig. I3.-Layout ofright-hand points.

MakinA Model Railway TrackA Method of Making "0" Gauge Tin-plate Points

By T. HADFIELD

(Continued from page 246, April issue.)

tacking, the sleepers can be properly solderedboth sides of the rail.and sleepers, and seethat all the rails are just the gauge ofapart inside.

The movable pieces of rail E and F cannow be tackled, and E must be first bentcarefully to curve template, allowing extralength for cutting off after fitting.

The filing of the ends to form the tongueportion must be carefully done and the

/ lower flat portion must also be cut away,as in Fig 14, so that it will fit close to thestraight rail when in the closed position.

If the shape of this rail is distorted infiling or fitting it can be rectified by openingthe round portion with a piece of kin. wireand hammering carefully back to shape. Ifpossible get a strong pair of curved nail

All the sizes I have already described ofrails and sleepers will be the same, butthe sleepers 2, 3 and 4 will be longer. Thesleepers can be cut to length and endsangled as shown. The curved rail portionis the same as the template, Fig. 12.

The pieces of rail B and C can be cutand ends mitred so that when fitted willmake the angle shown ; solder these togther,flooding the inside of the top with solderand the excess can be filed off afterwards.Then cut lengths of rail for A and curvedpiece D, which must be shaped to template.

Place sleepers in position on the diagramas set out on the board. The rails A, B, Cand D are then placed in position on thesleepers and adjusted by means of the gauge(Fig. 1), and if some flat weights are placedon the top of the rails they will hold steadywhilst being tacked with solder. After

I

Fig. 1.4.-Method of formingthe tongue of the points.

Fig. 15.-Detail of the pivot plate.

/0';

2'_

scissors ; this will help a lot, as thetin is very thin.

'With these scissors you can easilycut up the inside of the formed railto cut away any portion that isnecessry for a close fit, and one mustremember that everything will depend

on this fit for the efficient working of thepconts, so don't be afraid of spoiling a littlebit of rail.

The same will hold good in the straightpiece F for ;he other movable rail, whenfitting to the curved fixed length D. Therails E anti I can be placed in position andmarked for bending to form the guide piece.To make this sharp bend file a nick in theback of the round portion of rail and withthe snips cut a nick in the flat portion andthe rail can then be bent easily, but mindyou don't breolr it through. To form the

Fig. i6. (Right).-The tie plate for the tongue

ends of the points.

Fig. 15.

I"

small bend at the tip of the guide portion,put a small piece of kin. wire in the railand grip with the pliers, when this bendcan easily be formed and it is only to guidethe flange of the wheel into the points.The two guide rails G and H can be cutand bent th,5 same as E and F with thepliers at the tips.

The piec: of tin plate 7 (see Fig. 15) canbe marked out from the diagram and cutand drilled for the pivot pin. This can bea small bolt or a rivet, but don't fasten ittill the final assembly. Place plate 7 inposition with the pivot pin and adjust Eso that when fitting close to rail A thereis about kin. space at the guide end forthe wheel rim. Then E can be tacked toplate 7. Adjust rail F in a similar wayon to rail D, but before tacking to plate 7do not forget to move E about 3/i6in. fromrail A.

The plate 6 (see Fig. P6) can be made andfitted under the tongue end of movable railsand can be tacked with solder to each.

This will now tie both rail E and F, andthey can be moved and tested for fit to seethat each fits snugly the rails A and D andalso that the space at opposite ends areabout kin. clear for the rim of the wheels,and the gauge, 'lin., is correct.

These rails may need springing with pliersto adjust but be careful that you don't puta kink in the formed rails.Testing

When all are correctly adjusted it is aswell to try a truck over them, and see ifthere is any binding of the wheels or anyattempt to jump, which can be rectifiedbefore all joints are finally soldered up.The two gu-le rails G and H can besoldered into position, again leaving kin. forthe flange of the wheels to pass. Finally theoperating crank 8 (see Fig. 17) can be madeof 16 G. brass, and fitted with rivets orsmall screws.

Some reader, may not like this methodof fitting the crank to operate the points, butthis can be altered to conform to the actualrailway method in having a vertical lever.My reason for using this flat crank is thatwith the vertical lever it always gets bentand strained when dismantling and packingthe rails away, but the flat one is morecompact, and further, the flat crank lendsitself to remote control of the point from acommon signal box, to operate with pull andpush stiff wire, when fitted up as a perma-nent railway layout, or it could be operatedwith electric solenoids.

/ "

3/g

Fig. I7.-Thc point opera-ting crank lever.


The Unit of LifeThe Cell and Its Mysteries

IT is only a little more than a hundred yearsago since it first dawned upon scientificmankind that all living things, from the

smallest crawling creature inliabiting the bedof a river or the floor of the ocean, up to theelephant or the whale, have all a cellularstructure. That is to say, any living entityis made up of one or more (usually very muchmore) single units or cells which, for a timeat any rate, are capable of pursuing anindependent existence.

If life possesses., any definite unit, such aunit is the cell.

We might define a " cell " as an enclosure.A prison cell, for example, conies under sucha definition. So, also, does a living cellsituated in an animal or in a plant. Both thelatter types of cell constitute organised unitswhich, in some as yet exceedingly mysteriousway, are permeated through and throughwith a principle of self -organisation, themanifestation of which we conveniently termLife.

More than that, each individual cell haswithin itself the power of giving rise to othercells of a like nature. It is a living machinewhich duplicates itself and so perpetuates itsspecies, to an indefinite extent.

In addition to the mass of separate cellsconstituting the flesh, nerves and muscles ofthe animal and human body, there are manyother types of cells, each having specialisedfunctions of its own. There' are, forinstance, the red corpuscles of the blood (afew billion of them altogether in each adulthuman body) whose function it is to carryoxygen from the lungs to all parts of the bodyand to carry back to the lungs the wasteoxidation products of the muscles and othertissues. Then there are the white cells of theblood-the " phagocytes "-which are theservicemen of the bloodstream, ever on thealert to pounce upon and destroy any invadingenemies in the way of disease germs or otherforeign matter.

Nerve cells. A high -power photomicrographshowing the individual cells comprising a humannerve. It is such cells which are responsiblefor the transmission of pain, impulse, or othersensory messages from the brain to any portion

of the body.

Again, in every animal body there are theepithelial cells which line the alimentary tractanti serve to absorb nourishment into the ,body. No less important, too, arc the variousgland cells whose function it is to dischargespecial compounds, such as :digestive juices,at various areas of the body.

Still more, we have skin cells, bone -formingcells, and even our very act of thinking is, in

some hidden way, the apparent product of theactivity of a very highly specialised set of cellswhich, in consequence of its mass appearance,has been designated the " grey matter."

Specialised CellsLike the plants, we-humans and animals-

are, so far as our anatomical 'make -ups areconcerned, nothing more nor less than mereorganised masses of countless special cells,each cell having its one definite function andperforming that function with a well-definedrhythm and regularity, to say nothing ofprecision, in the body.

The anatomist or the scientist who pains-takingly dissects the plant or animal body inhis quest for the source of life and growthgets down at last to the single cell. And therehe stops. He can go no further. Apparently,he has reached the very unit of life, just as achemist detecting a single atom would at oncerealise that he had reached the unit of matter.

It is not proposed here to deal with any ofthe multitudinous ways in which masses ofcells are assembled together to form even lowlyanimals. We must, on this occasion, con-centrate our attention on the character of thesingle cell, which, after all, forms the mostfundamental problem in the whole range ofbiological physics and chemistry.

While some cells are exceedingly minute,the majority of them come, in size, just within

the limit of humanvisibility, being tothe naked eyemere specks of jelly-like matter.

A number oflowly forms ofanimal life com-prise single cells-only, and thesespecial cells areendowed with allthe various attri-butes of life, suchas ingestion,assimilation, sensi-

A drop of human blood viewed under themicroscope. Note the individual red cells of the

blood.

tivity to stimuli, and so on. These specialone -cell animals mainly inhabit the mud atthe botroms of ponds and slow streams. Theyarc known as the protozoa in contrast to the

A microscopic view ofa connected chain ofsingle cells forming thegreen slime which col-lects in ponds and

ditches.

metazoa, or multi -cell animals which consti-tute the higher forms of life.

It is therefore to the protozoa or unicellularorganisms that we must go whenever we wishto study the mysterious phenomenon of animallife in its first beginnings and in its simplestforms.

The Amoeba.Crawling on the surface of the fine mud at

the bottoms of shallow field ponds and poolsexists life's simplest cellular organism-theamoeba. It is a form of life which is wellknown to natural history students, micro-scopists and the like. The organism iscommon enough, and anyone having a smallmicroscope can study its many marvels at hisor her leisure.

The amoeba constitutes a single, solitarycell of clear, jelly -like matter. As ordinarilyfound, its essential transparency is usuallymarred by the existence within it of numerous,opaque specks, but these are merely inclusionsof particles of food which the amoeba hasingested and taken temporarily into itssubstance. In actual size, the amoeba is only

Life's simplest form-theAmoeba. This singlecell organism consists ofa , speck of protoplasmsurrounding a dark"nucleus." Theorganism is able tocrawl about by meansof protruding " pseudopodia," or " false feet."


Luminous cells. A microscopic view of thesingle -cell organisms which impart luminescenceto the waves of the sea round our shores at

certain times of the year.

about a hundredth of an inch across, and ithas practically no thickness. It is merely aspeck of living jelly, being almost structurelessin make-up.

Despite, however, its essential anatomicalsimplicity, this speck of jelly can sense thepresence of its food, it can " walk " to thelatter, can ingest (or digest) the particle offood and afterwards cast away the unrequiredresidue.

It is a highly sensitive creature. If youtouch it with the fine point of a microscopeneedle, it instantly shrivels up into a globuleof jelly. A mild electric shock has the sameeffect on it, as, also, has strong light orultra -violet irridation.l

The scientist could easily construct a minuteamoeba for himself out of a speck of gelatineor albumen, but his creation, although identicalin pattern with the real thing, would be deadand immobile. The life principle would belacking.

"False Feet "A most remarkable feature of the living

Black pigment cells in the skin of a frog.Note the almost identical pattern of all theindividual cells. (Reproduced from a photo-

micrograph.)

amoeba or single -cell organism is its strangemethod of slow locomotion. This it effects bythrusting out of its irregular sides protrusionsof jelly -like matter which are technicallyknown as pseudopodia, or " false feet." It isseemingly able to extrude these gelatinousappendages in any direction. Hence, whenit is in the vicinity of a particle of food, such,for instance, as a minute fragment of decayingleaf, the amoeba pushes out its " false feet,"which latter slowly surround the food particle.

By this mechanism, the amoeba completelysurrounds the grain of food, absorbs it intoits system, and, after extracting the availablenourishment from the food -grain, simplyflows away from the latter by means of its

false feet " mode of progression.Microscopists have been able to, obtain

living amoeba entirely free from ingestedmatter. In this condition, the cells areperfectly transparent. All the semblance ofinternal structure which they show is acentral nucleus, dark in colour and apparentlyenclosed in a cyst or transparent bag withinthe jelly -like body of the organism.

ProtoplasmSuch is a feature not only of the lowly

amoeba but of all living cells. Hence it seemsto be a fact that the cell unit of life is com-posed of a minute nucleus surrounded withclear jelly -like matter to which the term" protoplasm " is given.

Attempts to investigate the chemical natureof protoplasm have from time to time been

A photomicrograph of asection cut through therind of an orange. Itshows clearly the massof oil -producing cells,and also the largeglands or reservoirs justbelow the surface inwhich the orange oil is

stored,

made, but all of them have failed. We know,of course, that this protoplasm, which is amaterial of the protein or albumen family, iscomposed of carbon, hydrogen, oxygen andnitrogen. That sort of rough " analysis isvery easy going. But when it comes todetermining exactly what particular type of a

compound proto-plasm is, or whatkind of a mixture ofcompounds it con-stitutes, then eventhe modern resourcesof chemical sciencejust fail, and failbadly, too.

Yet we must notbe hard on thechemists in thisconnection, for theproblem of thenature of protoplasmis a most formidable

one. Most probably, the jelly -like materialexistent in cells, and which we term proto-plasm is inherently a complicated mixture of,complex nitrogen -containing materials, thecorrect identification of which may not bemade for many years yet.

But besides the essential pfotoplasm, eachsingle cell contains a little sugar (or mixture,of'sugars); some fat (or, alternatively, a fat -like material), together with a large amount ofwater end a few mineral salts, such as thechlorides and sulphates of sodium, potassiumand calcium.

The single cell, clear and transparent as itappears to the microscopist's vision, is,therefore, in reality, a most complex affair.More than that, it appears to be electricallypolar, having areas of negative ar d areas ofpositive potential, these, doubtless, beingaccounted for by the presence of ionisablcsalts, such as sodium chloride.

Electrical InterplayIt seems clear, therefore, that the cell, or

life -unit, is an enclosure within whichchemical and electrical forces have their playand interplay. Possibly the electrical forces,consequent upon the ionisation of the mineralsalts, form the mainspring of the cell's energyand thus preside over the balance of itsinternal chemical reactions. But whether thisat present extremely hazy notion of theinternal mechanism of the cell is sufficientfor us to conceive the cell as a mere machineoperated, in some as yet unknown complexmanner, by electrical forces instead of acomplicated organism dominated by someexternally derived " life-force ", is a matteron which modern science cannot express anyclearly defined opinion. .

The function of the nucleus in the cell isvery obscure. It seems'to have -something todo with the cell's power of propagating itselfby " fission" or dividing -up into two separatecells, as is its wont. But, apart from thisfunction, the nucleus exerts some powerfulbalance over the general well-being and

An octopus of curponds. The Hydra, aminute creature living inditches and stagnantwater. It consists of anumber of cells, someof which are extensibleand form tentacles -whichserve to capture andretain Minute objects of

prey.

276 NEWNES PRACTICAL MECHANICS May, 1945functional activities of the cell. Destroy, oreven slightly damage, the cell's nucleus, andthe remainder of the biological organism ormechanism at once refuses to function. Thisis true of all cells, not only of the amoeba cell.

Dissecting CellsBy using very fine and almost invisible

silica threads actuated by precision screwsattached to a microscope stage, modernresearchers have found it possible in somesmall way actually to dissect living cells.They find that if a portion of the cell'souter envelope (containing the transparentprotoplasm) is torn away, the cell has the powerof repairing the damage and of thereaftercontinuing its function. But, on the otherhand, it is found that if the extremely thinsac or envelope surrounding the cell nucleusis in any way torn, ruptured or damaged sothat the contents of the nucleus (or evena portion of them) pour out or infiltrate intothe clear protoplasm the whole cell instantlydies.

It almost seems as if the contents of thenucleus form a very active poison for theremainder of the cell, although probably,the whole irrevocably destructive effect ofpartial rupture of the cell nucleus may bebased upon the neutralisation of electricpotentials existing within the organism.

Is life, therefore, in this simple, lowly,ultimate guise, the product of purely electricalor chemical forces, as we have previouslyqueried, or does it essentially consist of someextra principle added to the cell mechanismfrom an external source ?

That, as Hamlet might have well remarked,is the perpetual question.

To those who conceive the life of a singlecell or small group of cells as being purelymechanical or electrical, one might offerthe following information :

The StentorThere exists a lowly fresh -water animal

known as the stentor. It has an uppertrumpet -shaped " head " attached to athread -like contractile foot or leg by meansof which it anchors itself to a fragment ofstone or a plant stem submerged in a stagnantpond or ditch.

When undisturbed, the stentor rears itselfupon its elastic " foot " and fishes for itsprey by means of a fringe of waving hairs(cilia) on its trumpet -like head. It has, also,the power of detaching itself from the plant,

The strangely shaped individual cells of a speciesof mould. Like the amoeba, they each constitute

one unit organism of life.

stem or stone and of swimming off to somenew place of attachment.

Now, some remarkable experiments havebeen made with the stentor, which experi-ments seem to prove that even an animalcomposed of a few single cells strung to-gether has some semblance of memory orassociation.

Sand BombingIn these experiments, fine grains of sand

were carefully dropped on to the head of thestentor. At the first impact of the sand, theorganism instantly retracted itself into aspeck of jelly. After a time, it expanded itselfagain. Further grains of sands were droppedon it, and with precisely the same result.After the sand dropping had been repeateda few times, the creature apparently became" fed up " with its circumstances, and, atlast, it released its hold and swam (or, rather,wriggled) away to another area.

After the stentor had aggin reared itselferect in its new area, the sand -grain droppingwas continued. This time, the stentor onlysuffered two or three repetitions of thisminiature bombing before it betook itself away

to another " safe area " ; and, finally, afterthe same creature had been carefully followedup and " bombed " with sand every time ittook up a fresh anchorage, it ultimatelywriggled away to a new place at the firstsand -bombing attack instead of waitingfor several of these " incidents " to occurbefore it finally made up its mind to changeits quarters.

"Memory " or Mechanism ?Here, plainly, is some type of memory or

experience -association in an organised groupor assemblage of almost clear, transparentprotoplasm cells.

It is difficult to regard this " mental "association as being just the result of someinternal electro-chemical balance within thestentor's cells, although, of course, at thepresent state of our knowledge, one has noright to deny such a possibility.

To the expert observer of the present day,the single cell, be it a specialised cell of humannerve, muscle, flesh or blood, or even themalignant cell of the germ or bacterium,appears mainly as a highly complicated, highlyingenious physico-chemical mechanism. Itobtains its energy by processes of chemicaloxidation, just as our bodies in the mass do,It propagates itself and builds itself up inenormous numbers into organised plants andanimals. Yet, at the same time, it shrewdlyretains its own essential individuality.

Animals are agglomerated masses of cells.Is the reverse true, and are cells animals ?Seemingly, they must be so in respect of thefact that they are endowed with animal life.

But whence springs their life ?Such a question must, as we have before

said, remain unanswered. Perhaps, after all,with ourvery inferior and hopelessly inadequateknowledge of life's unit, the cell, we areexperimenting with and theorising over, notthe fountain spring of animal and plant lifeitself, but, rather, with the material unit ofmechanism by means of which and withinwhich the outside principle of life is enabledto make its appearance.

Such, it would seem, is the most rationalexplanation possible, at our present level ofknowledge, of the cell's most peculiar and, atpresent, most inscrutable mystery.

Life's unit is clearly demonstrable to oureyes. We can see it working, and we havesome dim knowledge of its mechanism, also.It is the initiation and direction of this life -energy within the cell which constitutesthe most perplexing mystery.

Lie Detector TheoryBy HEREWARD WAKE

LIE-DETECTING apparatus is attractingthe attention of criminologists the world

over, the U.S.A. probably being ahead ofother nations in its use and applications.Briefly, the theory is as follows :

For a formal test the breathing ratio istaken with a prieumograph and an instrumentcalled simply a psychogalvanometer whichregisters a sweat reflex in addition to a systolicblood -pressure variation. There are otherchecks as well ; but the fundamentally sig-nificant data is derived from the blood -pressure, the apparatus employed being butaids to formal checking.

Recording Blood PressureThe sphygmomanometer is that instrument

with which doctors take blood pressure, abandage being placed on arm and leg of thesubject and inflated, the air being then slowlylet out, a -dial recording the pressure. Afterinflation, the blood flow is stopped, then asthe air is released the first pulse beat isfelt by the operator. That means the blood

vessels' pressure and the bandage air -pressureare equal, so that the dial records bothpressures, the readings being rapidly takenwhile the suspect is being questioned, enablingreading to be graphed against answers.

The assumption is that it takes moreenergy to lie than to tell the truth, as energycomes from the central nervous system, thatis, from the motor centres of the head brain.This energy, inevitable if a lie is to be told,also affects the heart-beat rate, causing aslight or large increase in the systolic blood -pressure. Thus a lie cannot be told withoutthe increased energy and the blood -pressurecannot help but be affected by the increasedenergy. Regardless how facial expression orvoice -tone is artificially controlled, controlover internal body mechanism is not possible,so that, theoretically at least, the better theliar, the better is he exposed.

The actual readings of the milliammetermake no difference as a general' level isestablished before the questions are put.

It is the variations from the general level thatare regarded as being significant. The levelfound as a control -level is thus a referenceone, the up and down fluctuations tellingthe answers. Readings vary from 130 to 135normally, but can go up to 156 to 16o-thesteadier the pressure, the more truthful theanswers. After -nervous effects or end -effectsare not considered, that is, readings takenafter the essential questions have been put,the nervous reaction of the suspect,when it is " all over " causing this.-Pro-ceedings of I.P.R.E.

PRACTICAL MECHANICS

HANDBOOKBy F. J. CAMM

12/6 or by post 13/.Obtainable from all booksellers or by post fromGEORGE NEWNES, LTD. (Book Dept.),Tower House, Southampton St., Strand,W.C.z.


THE WORLD OF MODELSFrom Time to Time in these Pages " Motilus " has featured Model Work which has aidedthe War Effort, and this Month the Space is Devoted to Models of Modern ArmyVehicles, the Prototypes of which form Part of the War Work of Rootes Securities, Ltd.

By "MOTILUS"

1:S

ilfJP f

Fig. 1.-The series of models, built to the scale of t loth actual size, which were shown at the Rdies Press luncheon.

As I have said before in PRACTICALMECHANICS, the value of models aswar weapons is considerable. They

have played and are still playing a great part

Fig. 3.-Model of the K.T.4 gun tractorviewed from close range.

in the training of the Forces, in operationalWork, and in the identification of enemy warmachines.

Models also serve a valuable purpose inkeeping records of progress of every hind, andin this issue I describe a specially interestingset of armoured vehicles, which appeared inmodel form at the luncheon held for the Pressat Claridges in January by the famous Rootesgroup of companies.

In his speech, the chairman, Sir WilliarnRootes, explained that now the security, ban

:had been partially lifted; he wa.4 able"t6 let hishearers know what the group (including as itdoes the Humber, Hilloan, Sunbeam, Talbott''Comrncr and Karrier companies) had been:doing during the war, and also a little of theiractivities in the vital pre-war years.

In 1936 they were called in by LordSwinton, the Air Minister, to start theoriginal Shadow Aircraft factory for theproduction of bombers. From the outbreak

of war up to June, 1944, one in every seven ofall the bomber aircraft the United Kingdomproduced came from the Rootes companies.

At the beginning of the war Rootes groupemployed some 17,000 workers. To -day onein every hundred in war industry is directlyWorking for the country through this groupof companies for one of the four Ministries,M.A.P., Admiralty, Ministry of Supply, orMinistry of War Transport.

Assisting the ArmyBesides the making of aircraft there has

been the overhaul of damaged craft andengines, and the group has put its motor carmanufacturing knowledge to the assistance ofthe modern army.

Sir William Rootes also stated, " Now wehaven't made any complete tanks-Mr. R. R.Stokes please note! But we have produced6o per cent. of all the armoured cars, 35 percent of all the scout cars, and in addition,More than 3,600 other armoured reconnais-sance vehicles."

To give just three illustrations of theversatility of the organisation's work they

Fig. 2.-The Marquess of Donegall examining the details of a model of the Karrier K.T.4glut tractor. -Also in the picture are (left) Mr. Harold Heath,. of Rootes Securities,

Ltd.; Mr. Alan Botwood and Mr. G. Geoffrey Smith.

278 NEWNES PRACTICAL MECHANICS

Fig. 5.-Humber F.W.D. Utility car modelled toilloth scale by Bassett-Lowke, Ltd., Northampton.

have made practically anything from millionsof bombs and fuse parts, to thousands ofside curtains for American Jeeps-and havetrained over it,000 Army personnel in theirown mechanical schools.

The vehicles modelled and on show at thePress Luncheon were seventeen in number :The Handley Page Halifax Four Engine

Bomber, Mark V.Humber Reconnaissance Car, Mark III.Humber F.W.D. Utility Vehicle.Karrier C.K.6 Bridge Girder Carrier.Special Humber Ironside Saloon built for

the use of Their Majesties the King andQueen and Members of the War Cabinetduring the London blitz,1940-I.

Humber Armoured Car, Mark IV.Humber Scout, Mark I.Humber F.W.D. Mobile Recording Truck,

as used by the B.B.C. on all war fronts.Humber Armoured Car, Mark III.!lumber Ironside, Mark I.Humber Armoured Car, Mark H.Commer Q. t5 G.P. Wagon.Humber Reconnaissance Car, Mark II.Karrier K.T.4 Gun Tractor.Karrier K.6 3 -ton Load Carrier (Winch

model).Humber Armoured Car, Mark I.Firefly Aircraft (Fleet Air Arm).

Owing to the wartime conditions whichstill prevail, there are a number of vehiclesstill to be modelled, of which, for securityreasons, no details can yet be given to thepublic, but all those mentioned here are, inthe words of Mr. Rowland -Rouse of Rootes

Fig.

May, 1945

Later it came into use with Indian troopsand others on many fronts in the varioustheatres of war. Fig. 3 shows a close-up ofthe model of the K.T.4 Gun Tractor,which is 'loth scale.

Humber Armoured CarIt is interesting to know that the original

idea of the Rootes Group producing ArmouredCars came from Colonel Leigh, of the IndiaOffice, in November, 1939. He made therequest that an experimental chassis of therear -engine type should be designed andbuilt, using as many of the standard unitsof the Karrier K.T.4 Gun Tractor chassisas practicable. Following this up, Sir William-then Mr. W. E. Rootes-and Mr. B. B. Winter,Engineering Director of the Rootes group,visited a number of Army units in France,

4.-Humber armoured car, Mark II, made to 1/ loth scale byBassett-Lowke, Ltd., of Northampton.

securities, Ltd., " old jobs," though never-theless a few details of their work makefascinating new reading to many of us.

K.T.4 Gun TractorThe photograph reproduced in Fig. 2,

and taken at the luncheon, shows the Marquessof Donegall examining the details of themodel Karrier K.T.4 Gun Tractor. Thisvehicle was manufactured in large quantitiesby Karrier Motors, Ltd., even before thewar, for the India Store Department, andused by the Indian Army on frontier work.

and were asked to press forward with anarmoured car production. The result ofthis was the Humber Armoured Car Mark I,which was designed, tested; and in servicein a very short time. Fig. 4 shows a modelof the Mark II vehicle, made to 1/loth scaleby Bassett-Lowke, Ltd., of Northampton.The prototype, in the natural course ofprogress, has been followed by the Mark IIand again by Marks TH and IV, each developedas a result of the experience gained almostdaily by the use of the earlier type.

Another Bassett-Lowke model is shown

6.-Humber reconnaissance cars Marks III and II, modelled by Bassett, Lowke, Ltd., Northampton.

May, 1945

in Fig. 5-the prototype of which is theHumber F.W.D. Utility Car, used in largenumbers on various war fronts, as a staff car,a pick-up vehicle and a mobile wireless unit.The same chassis in turn is also the basisfor the Humber Front Line Ambulance, andfor the B.B.C. mobile recording trucks.

Reconnaissance CarsHumber Reconnaissance Cars Marks II

and III are the subiects modelled in Fig. 6.This particular vehicle was developed fromthe original Humber Ironside, designed incollaboration with General Ironside, who atthat time was C.I.G.S. The vehicle wasmounted on the Humber Super SnipeChassis and was originally intended for HomeDefence. The Mark II car was mounted on


the same chassis, but the later Marks weremounted on the four-wheel drive chassis.Reports on the wonderful work done bythese scouting vehicles has come from allfronts.

As regards the craftwork contained in thewhole series of scaled vehicles, these havebeen built to a scale of Moth actual size,which allows he model maker to show a fairamount of detail. Studying the close-uppictures, it will be seen that the reconnaissancecars have guns fitted in the turrets and gunsforward. One of the most interesting modglsis the Humber staff car (Fig. 5), which hasall the interior fitments modelled, seatsupholstered in leather, steering wheel gear,levers, etc., and also collapsible map table.The bodies of the models were made of

279

selected hard wood and the chassis andfitments of metal, while the tyres werespecially moulded to scale in rubber by thefamous firm,,of Dunlop.

Although this article only covers a few ofthe models in this interesting series, it will berealised that model work of this type, inaddition to making it easier to comprehendthe purpose and external details of thevehicle involved, is an invaluable record: ofthe armoured side of the modern Army ofthe Allies.

At the luncheon, where they were displayed,were many well-known personalities in theengineering world, as well as from FleetStreet, and among them we mention, lastbut not least, our worthy editor, Mr. F. J.Camm.

Uses for Repair PlatesAn Effective Method of Carrying Out Simple Repair Jobs at Home

IN many households to -day, when " makedo and mend " is the rule, there are many By " HANDYMANsimple repair jobs to furniture, and other

articles, which can be cheaply and effectivelycarried out by the use of repair plates. Theseplates, which are made of sheet brass or iron,are obtainable in various sizes and shapes,as shown in the accompanying illustrations,

Fig. I (Right). -Method of repairinga loose chair leg.

Fig. 2.-A corner of apicture frame repairedwith an angle plate.

and are provided with countersunk holes forfixing screws.

Loose JointsA loose joint between the seat rail and leg

of a chair can be made firm again by screwingan angle plate in the corner, as in Fig. 1,after applying a little hot glue to the joint.

Picture frames sometimes become loose atthe corner joints owing to a fall. In suchcases it is a simple matter to screw on a thinbrass L-shaped plate, as in Fig. 2, aftergluing the joint.

Loose joints are a common source of troublewith front garden gates, a broken tenon oftenbeing the cause. This can be remedied bymeans of an iron T-shaped repair plate, as atA (Fig. 3). When a top rail joint of a gate

-iworks loose it can be strengthened -in thesame way by a repair plate, either of anglepattern, or straight, as at B (Fig. 3).

If the repair plates are fixed on th4 insideof the gate, with the correct size screws, sothat the heads of the screws come flush withthe surface of the plates, and are paintedover the same colour as ie gate, they willhardly be noticeable.

Fig. 4.-Details of a neat repair to a fracturedpiece of furniture.

it

Fig. 3.-How repair plates can be used for strengthening loose joints in a gate:

FracturesWhere an upright, or leg of a piece of

furniture becomes fractured, it can be madegood by fixing a repair plate, as shown in Fig.4. The wood should be recessed with a chisel

Fig. 5.-How a corner of a \drawer can he strengthened.

so that the plate can be screwed in place flushwith the surface of the wood. It would be aswell to apply a little hot glue to the crackedpart before finally fixing the plate.

Repair plates can also be used for strength-ening the corners of boxes, and drawers, asshown in Fig. 5.Deck Chair Repair

The weak parts of the framework of afolding deck chair are usually the notched

Fig. 6.-Using a repair plate to mend a frac-tured deck chair member.

parts of the sloping members which take thehorizontal struts for adjusting the position ofthe seat. These members sometimes fractureat one of the notched portions, as indicatedat C (Fig. 6).

In such cases a strong repair can be effectedby the use of a stout brass repair plate. Ifthe faulty member is completely severed,apply some strong waterproof glue to the twofractured surfaces, and fix the joint with oneor two panel pins to hold the parts togetherwhile the glue is setting. Cut a recess on theunderside of the member to take the repairplate, and fix it in place with four countersunkscrews, as indicated in the sketch.


Masters of Mechanics -102

John GutenbergThe Story of the Invention of Printing

invention of printing by means ofseparate and movable types is generally

'r hailed as one constituting a triumphof invention which well-nigh revolutionisedthe habits of mankind.

Its initiation necessitated the mind of amaster mechanic no less than that of acreative artist, for the early printing typeshad to be laboriously cast from metal,accurately hand -cut and finished, assembledin " frames " and then placed in presses ofa then novel design.

History still offers a few unsettled problemsto the individual who would take uponhimself the task of tracing the genesis ofprinting to its earliest origin. Some saythat printing by means of movable typeswas known to the Chinese in Old Testamenttimes, but all such statements merely begthe question, since it has, unfortunately,become all' too common to relegate to theancient Chinese origins which cannotaltogether be determined from the knownrecords of history.

The art of block printing is very old. Youdraw a design on the smooth surface of ablock of wood. Then you carefully cut awayto a depth of about a third of an inch all thewood surrounding the design so that the latterbecomes a projection on the wood surface.You have then a form of wood block," andby inking the design on the block you canmake crude printed copies of it on paper.

" Block Books "This sort of thing was known and used

for a long time before printing by means ofseparately assembled types came into being.In fact, a few people even went so far as to'cut letters in wood blocks and to use suchblocks for printing from, a process which,no doubt, they derived in some way fromthe time-honoured Chinese picture -writingmethods. A few of these " block bookscompeted with the manuscript copies ofbooks which were then usually the productsof painstaking and industrious monasticscribes, although, for most purposeS, themanuscript copies were invariably preferredto the products of this block printing.

Printing, as we now know it, was given tothe world when it first dawned upon a humanbrain that it would be possible to constructseparate letters in wood or metal and, afteraligning these together in the form of words,to make ink impressions of them on paper.

One historical narrative assigns the abovefundamental idea to the brain of a Dutchmannamed Lawrence Coster, who was bornabout 1370 and died about 14.40. Coster livedin the old Dutch town of Haarlem. He wasa block printer by trade, and a persistentstory has it that he took pleasure in cuttingout letters in the smooth under -bark oftrees for 'the amusement and instruction ofhis grandchildren. One day, while engagedin this occupation, he noticed that a freshly -carved wooden letter which was still moist,with the sap of the tree gave an impressionof itself on a fragment of parchment in whichit was wrapped. This gave the worthy Costerthe idea of printing by separate types, and,before long, he had made a quantity of woodentype for himself, designed a press, and hadmysteriously announced his invention to hisassociates in Haarlem.

So the story has it. The narrative first cameto us in the writings of one Hadrian Junius,another Dutchman of the sixteenth century,

who stated that it was passed from onegeneration to another " as a lighted torchpasses from hand to hand without beingextinguished." In our times, however,Junius's picturesque story is universallydiscredited in consequence of intensiveinvestigative work which has been put intothe life career of another early block printer,by name John Gutenberg, of Mainz, who isnow claimed by all recognised authorities asthe true originator of type printing.

John Gutenberg. From a portrait taken in hislater years.

Gutenberg experienced a comparativelyrough life. He was one of invention's" unfortunates." Neither fame nor richescame to him as a result of his invention.He was looked upon in some ways as a rascaland an impostor, and when, eventually, the

Reproduction from an old wood block depictingthe early printers of Gutehberg's time at work -

with a wooden hand -printing press.

practical benefits and utility of his printingsystem began to be appreciated, his inventionwas pirated right and left. Hardly anyonerose up to champion Gutenberg's claims topriority in the matter of printing by meansof separate and movable types. He got intofinancial difficulties, became, even, involvedin semi -political struggles, sank into relativepoverty and (according to a legend) wentblind before he died about February, 1468.

John Gutenberg was born at Mainzsome time between 1394 and 1398. Hisfather's name was Friele Gensfleisch. Hewas the youngest of three children ; andwas born while his parents were living onthe estate of Gutenberg, in Mainz. Hisparents took the name of " Gutenbergfrom the estate on which .they lived, and theirchildren did the same.

We know little about John Gutenberg'searlier career. His father was one of thetown nobles of 'Mainz, but Mainz, at thisperiod, was in rather a bad way. It hadundergone several decimating visitations ofthe dreaded Plague, and many of its industrieshad been lost: The town itself had got intodebt, and its inhabitants found themselvestaxed exorbitantly. There was nothing butstruggle and strife in the place, a fact whichresulted in many people leaving the town andseeking a living elsewhere.

Among these civic emigrants was JohnGutenberg. He went to Strasbourg, somedistance away. Legal documents prove thathe was at Strasbourg during the years 1434-5444. For a portion of this time he wasa member of the goldsmiths' guild, a fact,however, which does not necessarily provethat he ever actually engaged in such work.Indeed, Gutenberg, during much of his life,seems to have been content to live off theproceeds of the family estate.

Secret ArtThree years after going to Strasbourg

Gutenberg entered into partnership withthree citizens of Strasbourg in a mirror -making bukness. The agreement respectingthis partnership still exists (or did exist inpre-war days), but from this purely legaldocument we are unable to gain any tangiblenotion of the true nature and aims of thebusiness. There appears to have been aquestion of some " secret art " which Guten-berg at that time was in possession of. Whetherthis " secret " was concerned in any way withprinting, who is to say nowadays ? Gutenbergmay have had alchemical aims, and havethought himself the possessor of somehitherto unknown chemical operation orprocess, fantastic or otherwise. On the otherhand, the idea of the separate and movableprinting type may have alighted upon himduring his sojourn in Strasbourg. Whateverthe " secret " was, however, it had, by theagreement, never to be imparted to any otheroutside person.

In 5445 Gutenberg returned to Mainz, hishome town. In the museum in that townthere was a small fragment of a printedpaper which is assumed to date from theabove year, and to represent one of Guten-berg's first essays in printing. Whether suchis the case, however, there is no telling.It does seem certain, after a consideration ofthe facts, that some time ardund the year1445 Gutenberg attained his first success inprinting, and that the world's first hand -printing press was invented by him either atMainz or at Strasbourg.


The Cradle of PrintingGreat controversy has raged around these

considerations, some authorities consideringStrasbourg to be the " Home of the Press,others asserting Gutenberg's home town ofMainz to be the " Cradle of Printing."

Whatever may be the truth of the matter,there is no doubting the fact that from theyear 1445 onwards Gutenberg engagedwholeheartedly in the new printing techniquewhich he had evolved. There is a story thathe carried out most of his early trials secretlywithin the desolate confines of an uninhabitedmonastery nearby.

What the modern world of technicalhistorians would like to know is exactly hoWand precisely when John Gutenberg got hisbasic conception of his printing invention.An educated man himself, Gutenberg mustundoubtedly have had a knowledge of manu-script books and of woodcut and block printing.As a goldsmith, he must have been somethingof a metallurgist and a chemist. We mustcredit him with some acquaintance withmetal working even although he may neverhave practised the goldsmith's trade commer-cially. He would, therefore, be familiar withthe mode of casting metals in moulds.

It would seem, therefore, that in this latterfamiliarity we have some clue to Gutenberg'sorigin of printing by means of cast types.Sand was used for metal -moulding previousto Gutenberg's time, as, indeed, it is in manyinstances in our own time. But John Guten-berg, having conceived the idea of makingmetal types for printing purposes, realisedat once that he could not adopt the sand -casting method, for sand does not form apermanent mould.

Lead MouldsInstead of sand, he selected a metal for the

purpose. This metal was a soft one-lead.The process which Gutenberg seems tohave worked was this.: he very carefullycut out his letters in brass, and, providingsome suitable mounting stick for these, heconstructed a number of metal punches,each punch being provided with a differentletter. Each brass punch was struck into asmooth -surfaced block of lead, therebymaking a clear impression of the letter,which impression would be used as a mouldfor the type.

At a later date, engraved steel puncheswere used instead of the weak brass ones,bun -with this alteration in detail, this methodof type -casting persisted for very many years.

Such was Gutenberg's invention of printing.Naturally the cast types were very rough.They had all to be carefully hand -finishedby grinding and polishing, a task whichwas tedious and time-consuming in theextreme. Yet it was a business which lastedfor centuries, almost, indeed, into our owntimes.

Smaller inventions of Gutenberg consistedof modes of " composing" or assembling histypes into the printed lines of letters, and ofthe construction of " frames " to hold theassembled type firmly in position under thepress.

The first press which this inventor usedwas an ordinary wooden linen press operatingon the principle of what we now term theold-fashioned office copying press. Gutenberghimself, does not appear to have done muchto improve the details of his press. To theend of his life he seems to have been contentwith converted linen presses of one descrip-tion or another. In fact, these old woodenpresses survived until the end of theeighteenth. century, when, about the year1800, the Englishman, Lord Stanhope,brought out the first iron printing press.

One of Gutenberg's first aims as soon ashe had perfected his printing method wasto issue a printed edition of the Bible. Forthis project financial means were essential.

Gutenberg, for this purpose, sought the aidof a citizen of Mainz named John Fust.The latter individual helped Gutenberg outto the tune of 800 gulden, a fair sum in thosedays. But this sum went nowhere. It wasquickly expended in preparations for theprinting of the Bible.

Legal ActionAgain John Fust lent a helping hand.

He, offered to pay an annual sum of 300

omint 4D mitiplitanttibulfit ntemulti ini

uteri= int,(1) ulti bit& onnn tftfoluo alit In tiroWit tuft-mita neje : giorit*dub taput tutiikXoce tomind dontoui : traubitutto fritto fim9(go tonniuitutu: ttfutteg quid biz fu

A reproduction of a page of one of Gutenberg'sbooks, showing the nature of the hand -cut and

hand -cast type which he used.

gulden to Gutenberg provided that Gutenbergwould let him have a share in the printingbusiness. This Gutenberg refused. Theresult was that there seems to have been afirst-class row between John Gutenberg andJohn Fust, the latter wanting his moneyback and resorting eventually to legal processin order to obtain payment.

Gutenberg, being the loser in the action,found his funds exhausted. Fust,'on the otherhand, went off and joined forces with onePeter Schiffer, and between them theymanaged to set up a press and to printseveral book editions. How they did thiswithout prior knowledge of the art is notknown. It is supposed, however, that, asa result of Fust's successful legal action,Gutenberg had to hand over his press, lock,stock and barrel, to Fust.

Reproduced from an old illustration depictingGutenberg experimenting with his printingtypes in a disused monastery near Mainz.

What line Gutenberg took immediatelyafter the affair with John Fust we are notaware. He seems to have occupied much ofhis .time in fighting what we would nowterm " actions for infringement " and inraising funds to undertake such activities.Nevertheless, he must, in one way or another,have continued actively with his printinginvention, for there is plain evidence that,in the year 1457, he was still in Mainz, andwas then engaged in operating a press inconjunction with a town councillor of thecity, one Konrad Humery. Whether thisindividual Humery played the role of financialpartner or formal employer of Gutenberg isa matter in dispute. It is, however, a detailof little consequence.A Political Refugee

Had John Gutenberg been satisfied byconfining his attention solely to printing hemight have well made a respectable fortuneand have lived out his days in peace. But therestless John seems to have been a man ofquick impulses, to have been possessed oflittle tact, and to have had a genius for rubbingpeople up the wrong way.

He became involved in political matters.They appear to have been exciting enough,so much so that Gutenberg found himselfobliged to flee from the town in 1462. Buthe quickly returned, his former zest forpolitical activities much quieted. Indeed,he was an old man at this time, although hestill possessed the spirit and the fervour ofyouth. He was a poor man, too, for hispress had been destroyed, and his meansof earning a living had departed.

A new Archbishop of Mainz had beenappointed by the Pope. He was a kindlyindividual, this Archbishop, and he tookpity on Gutenberg, realising his inner creativegenius, and the many rough deals which Fatehad meted out to him.Exempt from Taxes

In 1465 Gutenberg entered the service ofthe Archbishop of Mainz (a document givesthe date as January r7th of that year). TheArchbishop provided him with food andclothing, gave him a small annual allowance,and arranged that he should be exempt fromall town dues and taxes. Thus circumstanced,the inventor of printing lived his life out underthe Archbishop's gentle protection. He issupposed to have gone blind about this time.

Old John Gutenberg was no longer aliveon February 25th, 1468, for a document ofthat date refers to his recent death. Hisdecease appears to have taken place in theJanuary or February of the latter year.

Such, very briefly, in the life -history ofprinting's first creator. It is an unsatisfactorylife -history from many points of view. Yetit is probably the only narrative whichhistorians will ever be able to piece together,for the footprints which this strange person-ality contrived to make upon the sands ofTime have, in many places, become hopelesslyconfused and obscured, while, in others,they have been obliterated altogether.

Like many another inventor, JohnGutenberg got little out of the g. me. Atfirst his new system of printing fromseparately assembled types was vigorouslyopposed by the book -copying interests.Soon, however, people began to realise thatan entirely new era had been introduced bythe invention of this type -printing. Whentype -casting became a specialised business,printing attained a recognised status. Itspread up and down the Continent and(through the efforts of our famous and justlycelebrated William Caxton, of Westminster)into England. There was now no rooting outof the new-fangled mechanick " inventionof printing as the contemporary manuscriptcopyists would have liked to have done.Printing had become a business and, assuch, had come to stay until the end ofcivilisation.

282

LettersNEWNES PRACTICAL MECHANICS May, 1945

tomReadersFuture Inventions

IR,-I heartily agree with the views set0 out so well by the letter from Prof.A. M. Low in your April issue, and amwriting a letter therefore to repeat a suggestionfor a remedy even though the time may belate.

An appeal should be made through authori-tative channels of our industrial world forthe promotion and development of anInstitution of Inventors.

This can be done through existing organ-isations with the addition of co-operation andcapital only. New buildings, organisation andmaintenance of new working staffs can comelater, if wanted.

The basis of organisation of an InventionInstitution can be divided into three mainsections :

(a) An experimental department for theinvestigation and 'correction of inventionsproved inefficient on commercial develop-ment in the first stages and for investiga-tion work in general in the various branchesof science applicable to industry.

(b) A department for the unbiasedanalysis of the scientific press, run on aloose-leaf system, so that information canbe bought as wanted at so much per sheet.

(c) A department for the reception,criticism or -rejection and introduction ofinventions to industry by correspondence,negotiation and exhibition, and to assistthe inventor in legal and financial advice ofan unbiased nature.Section (a) could be created by an expansion

of our Department of Scientific and IndustrialResearch, any research departments of ourexisting institutions, associations and univer-sities working in co-operation with them, theformer being the centre -depot foi all.

Section (b) could be created through ourexisting institution-A.S.L.I.B.-working asthe nucleus of a central collecting station,introducing its photographic method ofabstracts. Ejsch institution could handle theperiodicals and publications dealing with theirown line of subjects, but all would produceresults in a standard loose-leaf system commonto all. This could be started now by theaddition of a few to their administrative staffs,these being chosen from the older brains of,the country, who would analyse the publica-tions of the last five years and have results'ready for the technical brains of our Forceswho are returning to the industrial world onthe establishment of peace and want to getup to date with the facts they have missedthrough their war activities. By practicaltrial over:a number of years it has been provedthat such a system is possible and I am surethe main part of the work could be achieved bysix to ten intelligent abstractors at each insti-tution in under a year. This would producesomething which would be thoroughly appre-ciated by those returning from the Forcesand would give a stimulus to trade in allsections which would be invaluable.o' Section (c) could be created by the informa-tion and organisation of the Institute ofPatentees which has done the work of sorting,correspondence and organising exhibitions ofinventive talent of this nature with successsince 1919 in a small but efficient way.

With regard to expenditure, this could beprovided by private enterprise, backed bythe Government on a scheme of seven years'allocation of £2,000 per annum subscribedby one to two hundred of our industrialpersonalities, costing each the equivalent of£200 per annum at the present rate of taxation,if their incomes exceed £to,000 per annum.The Government's backing could be providedby the profits of the Patent Office, which

understand are in the neighbourhood of£200,000 per annum. Such a scheme has hadpractical proof both before and during the warby the Mellon Institute of America.

I am sure th4t the subject is one of firstnational importance now and one that isgrowing as peace comes nearer in sight, asour main Allies in war will become ouropponents in peace.. National effort shouldbe devoted to that of the quickest developmentand maintenance of our export trade, and nobetter stimulus to that can be the introductionof our inventive talent to industry throughunbiased channels such as an institution.-SIR A. MOIR (Westminster).Ultra -violet Ray Lamp

SIR, In the March issue of PRACTICMECHANICS there is an article by K. K.

Thomson on an Ultra -violet Ray Lamp. Itis based on the assumption that the innerenvelope of the standard 25o volt 400 wattmercury vapour lamp is made of quartz ; thisis incorrect.

I obtained an Ediswan lamp of this type,fitted a choke, etc., and tried it on my armfor four hours in half-hour periods, decreasingthe distance from ift. to Sins. No pigmenta-tion resulted.

I then acquired an old lamp and broke upthe inner envelope. Extracting a large piece Iheated it in a flame until hot, then dipped itin water; it was covered with a network ofcracks. Had this been quartz it would nothave cracked, having practically no linearexpansion. On making inquiry of one of thetechnical staff of B.T.H., I was told the400 watt standard lamp is a low pressurelamp and toughened glass is sufficient for theinner envelope. The 8o watt and 125 watthigh pressure lamps have a quartz innerenvelope. That a special method had to beused to seal the wires in the tube since thewires melted before the quartz.

The lack of necessity for it, together withthe difficulty of production, make it' unlikelythat any of. the manufacturers use quartz inthe standard 400 watt lamp.-A. C. WILSON(Glasgow).

SIR,-With reference to the article onultra -violet ray lamps in the March

issue of PRACTICAL MECHANICS I should liketo draw your attention to the following errorswhich have occurred.

(t) The commercial Mercury vapour lampof 400 watts is not supplied with a quartzinner tube. This apparently only applies tothe smaller lamps, 8o and 125 watts.

(2) Your contributor describes ultra -violetrays as of long wave -length; as is well knownthey lie in the region 2,000-4,000 Angstromunits, and are therefore much shorter thanrays in the visible spectrum.

(3) It is possible to obtain efficient reflectionof the ultra -violet by means of polishedaluminium. At least 8o per cent. reflection isobtainable at 2,500 A., and about 90 per cent.from 3,500-4,000 A. AS the article statedthat such reflection was not possible, thisinformation may be of assistance to readers,in obtaining more efficient operation.-G. L. ASHMAN (Tottenham).

.SIR,-On page 188 of the March number.ofPRACTICAL MECHANICS and included in

the article " An Ultra -violet Ray Lamp "there reads as follows

" These rayl, which are of long wave-length, have very little penetrating power...."

Should not this have read " short " wave-length?-C. J. WILLIAMSON (Scalloway).

[You are quite correct. The paragraph shouldhave read : " These rays, which are of short-wave -length have very little penetrating power.. . ."-ED.J

Fighting Forest FiresSIR,-It has been- with much pleasure that

for some time past I have perused yourvery interesting publication, which is par-ticularly welcome in the absence of similarAmerican publications, and which in anycase supplies information of a kind that theydo not.

One particular matter that has greatlyinterested me for a number of years is thatof scientific fire fighting, fire control, and fireprevention. Now it is probably not muchknown outside Australia but it is a factnevertheless that this country in general, andthe State of Victoria in particular, isundoubtedly the worst forest fire and grassfire country in the world. Until recent years" black Thursday " of 1851 was consideredthe worst bush fire period in the State'shistory, but in 1939 there arose a holocaust ofa nature which the writer feels certain hasnever been equalled in the United Statesor any other part of the world.

Day after day for a period running intoweeks there raged an inferno that consumed

..three-quarters of the forest lands of theState causing damage to timber alone estimatedat about eight million pounds.

Subsequently, early in 1944, there arose aconflagration, this time confined to severalof the best grass lands of the State in whichmany miles of the foremost grazing areas werelaid waste while at the same time the greatelectrical generating centre at Yallourn, abrown coal mine area about too miles fromMelbourne, was very nearly wiped out.

The severity of both these fires may bejudged from the faot that in the fires of lastyear thirty people were either incinerated orsubsequently died of burns, while in those of1939 seventy people perished.

Damage due to the latter fires was estimatedat £2 million, yet the -community slumberson, the State Government only under pressurebringing in a bill to create a country fireauthority.

The bill which soon became law was basedon the recommendations of the Royal Com-mission, a county court judge, who wasappointed to inquire into the outbreaks.

His recommendations were based on dataof American origin ; the writer has sinceperused a considerable amount of data of thistype and formed the opinion that Americanforest fires are as nothing compared withthose of Australia, much of whose one percent. forest area may yet be obliterated, whilea further destruction of grazing lands and stockmay produce a meat shortage of a kind neverbefore known.

Knowing something of this menace formany years, the writer gladly undertook in1936 the task of assisting a Russian engineerwith tests on the fire extinguishing pro-perties of certain chemicals. They werehighly successful but it has long been apparentto the writer that to have any real effect onthe enormous fronts on which such fires burn,sometimes one hundred miles or more, theonly practical way would be by the releaseof fire extinguishing smokes or vapours fromaeroplanes or by dropping containers fromplanes either into the fires or in the path ofadvancing fires.

This point was discussed with the Russianwho said he did not think that TitaniumChloride had any fire extinguishing properties.

Be this as it may, any suitable formula thathave would be very welcome here and thewriter would greatly appteciate any helpgiven in that direction. I have read withmuchinterest brief mention of German claims tobe able to fire -proof forests but would welcomefuller information. N.P.M., April, 1941.There is also the question of protection forfire-fighters.

While the provision of asbestos suits andsmoke filters may be practicable for members

May, 1945 NEWNES PRACTICAL MECHANICS 283of country fire brigades, something simpler isneeded for the ordinary country resident whomay be called uppon to defend his home orthat of his neighbours, hence the writerlearned of experiments by the Royal AirForce on immunity from petrol fires withgreat interest. It was described in the October,1941, issue of Newnes PRACTICAL MECHANICS.

There is also the bombarding of smokedescribed in the April, 1941, issue-conditionssimilar to those described have been knownhere ; more information would be appreciated.

There is also another matter of a kind whichis of much interest to the Commonwealthauthorities here, namely, that of the MellonInstitute mentioned in the June, 5941, issue.

I have forwarded a copy of this article tothe relevant minister, who referred it to theC.S.I.R. which, prior to learning of it, wasinclined to dispute that the Mellon Institute

and stated rather that it was an institutionwhich offered research facilities to industry.

I would welcome any additional supportingevidence.

A further matter which is of much interestto the local mining authorities is that ofprevention of silicosis and miners' phthisiswhich is common in any country where goldmining is carried on. Hence more completeinformation re the McIntyre -Porcupine minesmentioned in page 436 of the September,1941, issue would be greatly appreciated.-E. W. CHAMBERS (Heidelberg, Victoria,Australia).

" The Phenomenon of Light "SIR,-In his article, " The Phenomenon

of Light," in the April issue, the authorstates in effect that in rushing away from an

was an organisation which helped inventors incoming light beam, the apparent speed ofthe latter still remains the same, and it takesno longer to reach you than it would havedone had you rushed towards it.

I have held a belief to the contrary. Here isan example to illustrate my point.

Suppose an observer to be a short distancefrom a railway station and in a good viewof it. He sees a train leave the station. Now,if he could recede from his observation pointat a speed greater than that of light he wouldsee the train going back to the station and thesmoke and steam returning to the funnel ofthe engine.

If my impression is a wrong one, perhapsthe writer of the article could explain why.-R. H. WALLIS (Bristol 6).

[Can our readers spot the obvious fallacy ?-ED.]

Items of .InterestPowerful Lightweight Tractor

ANEW lightweight tractor capable '''ofdrawing a two -furrow plough in the

heaviest soil, and with a three -wheel designwhich gives it an extremely small turningradius, has just been announced by Mr. DenisKendall, M.P.

The motive: power of this new tractor willbe, provided by the 6 h.p. (rated) three -cylinder engine (developing 20 h.p. in thetractor), designed for the Kendall -Beaumontcar, which is expected to revolutionise thesmall -car market after the war both in priceand performance.

The new Kendall tractor is expected to beput on the market as soon as tests are com-pleted and will cost k Too, a figure that shouldbring it within the reach of practically everysmall farmer.

The three -wheel design will permit thetractor to be used for both ploughing androw -cropping without any alteration to thewheel arrangement. Mass production, at therate of 5o a week, is expected to begin withinthe next three months. The tractor will bemade at Grantham, Lines.

Lighting by BalloonsWHEN the dim-out ceases to modify the

lighting of our streets and normalillumination is restored; there will be anopportunity for new methods of lighting tobe adopted.

It has already been proposed to illuminatelarge ground areas by means of captiveballoons furnished with light -reflecting sur-faces, in combination with searchlight appara-tus intended to direct beams of light uponthese surfaces.

Relating to such a method of illuminationis a device for which an application for apatent in this country has been accepted.This invention is designed to ensure thatbeams of searchlight are continually directedtowards a balloon's reflective surface.

The nets contrivance arranges for thesearchlight automatically to follow or respondto the movements of the balloon whenairborne.

For Pipe SmokersTNNUMERABLE attempts have been made1 to produce an ideal tobacco pipe. It isoften said that a pipe is the most. hygienicmethod of smoking ; but even this method isnot without drawbacks.

When a pipe is being smoked, moisture isformed at the bottom of the bowl. Thismoisture causes the lower layers of tobaccoto become damp and unsmokahle. Hence acertain amount of tobacco has to be thrownaway each time the pipe is smoked.

Hitherto the solution of the problem hasbeen essayed by furnishing an absorbentspiral through which the smoke has to pass.However, this filtration has a tendency toeliminate the aroma from the tobacco smoke.

In the case of a new invention which hasmade its debut, the bottom of the bowl of thepipe consists of a removable plug, in the

HOLIDAYS AWAY FROM HOME_EDITOR'S ADVICE

OWING to paper restrictions you would. be well advised to ask your news -

'agent to reserve your copy of PRACTICALMECHANICS until you return, if you aregoing away for your holidays. Otherwiseyour copy may be allocated to the personwhose name is next on the newsagent'swaiting list, and this will lead to difficultieson your return.

Should you so desire, your newsagentwould probably agree to post copies to yourholiday address if you pay postage. Inany case, please help by letting him knowin advance what you wish him to do, asit will not he possible to increase suppliesto holiday resorts.

hollow of which is a spiral of paper ,to serveas a ventilated platform for supporting thetobacco.

It is an advantage if the inlet to the mouth-piece is practically level with t14 top of thespiral.

Non-skid TyreAN improved non-skid tyre tread is the

object of another invention for whichan application for a patent has been acceptedby the British Patent Office. It is claimed forthis device that it has many of the advantagesof treads with either large or small volumetread anti-skid configurations, while at thesame time avoiding their faults.

The new device aims to provide a tyretread construction that is stable and resistsskidding without localized injury either tothe tread or the carcase of a tyre.

This invention has a tread formed with anumber of anti-skid tread elements or con-figurations. All the sides of these are serrated,forming small ribs projecting outwardly fromthe sides and spaced in relation to the tyreaxis.

Resilient SeatsAN inventor has devised a contrivance

relating to beds, seats, etc. He pointsout that for these articks it is usual to employ

coil springs, covered by upholstery. Thereare disadvantages associated with this method.The springs tend to weaken or break, or theysag at certain parts.

One object of the invention is to providea seating surface which may be easily sub-stituted for worn seats.

The invention comprises a resilient surfacefor seats composed of a series of spaced flatelastic wholly rubber strips. At their endsare openings for the reception of anchoringmembers carried by the frame for supportingthe resilient surface.

Ipswich and District Society of Modeland Engineers

AS a result of the efforts of a few veryenthusiastic model engineers, a meeting

was arranged on March 4th at the PictureHouse, Ipswich, which was kindly loaned bythe management for the purpose, with theobject of forming a Model Engineers' Clubfor Ipswich and the surrounding districts.Thirty-seven very keen supporters were inattendance, which left no doubt that the clubwould be a great success.

Mr. Braid, of Messrs. Reavell and Co., Ltd.,was elected chairman, also were all theofficers.

The object of the club would be to promoteinterest in anything engineering by means oflectures, papers and friendly discussions, forwhich monthly meetings are to be held.Negotiations are well in hand to acquirepremises for a club room and workshop, alsoa track for miniature passenger -carryinglocomotives, some of which haVe alreadybeen built, and others are in the course ofconstruction.'The hon. sec. is Mr. K. W. Day, 14,

Ashcroft Road, Ipswich.

CORRECTIONS" Bristol Hercules Engine "IN a short description of this engine whichI was published in the January issue of" P.M. " it was stated that the sleeve con-tained foUr ports. There are, of course,only three ports, one for inlet, while theremaining two serve alternately as inlet andexhaust.

" Instruments for Cars and Aircraft "OWING to a draughtsman's error the

drawing of a small rotary pump onpage 524, January issue, shows the rotorstoo small. The peripheries of these- wheelsshould run as close as possible to the casing,and not with a clearance.

284 NEWNES PRACTICAL. MECHANICS MaV, 1945

QUERIESGAENQUIRIESA stamped addressed envelope, three pennystamps, and the query coupon from the currentissue, which appears on back of cover, mast beenclosed with every letter containing a quisry.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, W.C.2.

Spray- for Insect PestsPLEASE suggest a non - poisonous chemical

addition to ordinary paraffin oil whichwould make it more deadly when used as a sprayfor flies and other insects. -4. J. Elmphray(Lerwick)

M..ETHYLsalicylate' (which is synthetic oil of

wintergreen) can be added to paraffin for flyspraying. It has a strong smell which all flying creaturesdislike, and it is not poisonous. Similarly, pine oil canbe used. Another liquid is Terpineol, which is pleasant -smelling. This can be mixed ao ao with methyl

' salicylate. These liquids should be mixed in theproportion 1 part (by volume) to every.8o or too partsof paraffin. They are obtainable from Messrs. A.Boake, Roberts and Co., Ltd., " Elleslie," BuckhurtitHill, Essex (emergency address), price about 3s. per lb.

It should be noted that the liquids will not actuallykill the flies ; they will merely discourage them.Materials for the making of fly -killing sprays (such aspyrethrum extracts) are at present unobtainable.

Cement Mixture for Making TilesCAN you give me the correct formula for

mixing cement with sawdust for makingtiles ? How is the sawdust treated, and whatproportions of cement and sawdust are neededfor a hard tile, as I want to polish same ?-S. J.Clark (Wolverhampton).MIX together 2 parts of sharp sand and r part of

clean sawdust. Take equal parts of this mixtureand Portland cement, and then slake it with waterin the usual manner. Place the resulting mixture inwooden moulds of the requisite size and allow aboutthree or four days for setting.

Another type of hard tile can be made by themagnesium oxychloride process. Take 2 pins sand,a part sawdust, i ) parts of calcined magnesite. Mixthese intimately. Then dissolve 4o parts of magnesiumchloride in 6 parts of water and slake the above mixturewith this solution .until a thickish paste is obtained.This is placed similarly into moulds and allowed to set.

Calcined magnesite and magnesium chloride areobtainable from any laboratory furnisher or chemicalsuppliers, as, for instance, Messrs. J. W. Towers,Ltd., of Widnes, or Messrs. Harrington Brothers, Ltd.,4, Oliver's Yard, 53a, City Road, London, E.C.t.All parts mentioned above are calculated by weight.

These mixes can be coloured, if required, by theincorporation of a small quantity of pigment, such asred oxide, green chromium oxide, brown ochre, etc.

The polishing of the tiles will have to be done byhand under water, using for the purpose an emery stoneand finally a softer abrasive such as whiting.

Paints for Shoes : " Liquid Waxes "CAN you supply me with a formula for making

paints for applying to the bottoms of ladies'shoes ? These paints are applied to the solesafter they have been scoured on a finishing

-machine, and when dried they are burnishedwith the pads of the same machine. As far as3 can make out, something is pequired of thenature of oil -bound distemper with waxes addedto help to create a shine in the burnishing.

Also, could you supply me with a formula forthe making of liquid waxes ? The wax is used ona chain stitcher. The reason for preferring liquidwax is that no gas or electricity is available forheating purposes, and in such circumstancesliquid wax has to be used.-J. A. Melvor(Drogheda).PAINTS for leather soles, etc., are usually of highly

secret composition and we cannot get any preciseinformation concerning them. They appear to comprisea mixture of an emulsified wax plus a certain amountof shellac, say about TO per cent. of shellac. We thinkthat you would be able to obtain more definite (andpossibly secret) trade information on this particularpoint if you write to the Director, British Boot, Shoeand Allied Trades Research Association, 19, BedfordSquare, London, W.C.I.

There are many types of so-called " liquid waxes."Some are merely solutions of wax or mixtures of waxesin various solvents. Others comprise wax emulsifiedwith water.

In your case we think that a wax solution such asthe following will serve your purpose well, but its exactstrength must be a matter for your own experiment andtrial. The formula is an average one for polishingpurposes :

Yellow beeswax, a oz.Paraffin wax (or, better, Ceresin wax), 4 oz.

Melt the above and then stir in gently :Turpentine (genuine), 17 oz. (to which, if required,

may be added about a oz. of pine oil or someother medium to give the product a pleasant smell).

Another type of " liquid wax " is the following :Turpentine (genuine), too parts.Shellac, xao parts.Zinc oxide, 3o parts.Methyl alcohol, za parts.

Mix all the ingredients together until the product isfairly free from lumps. Then strain through coarsecloth, and bottle. This preparation dries in the airafter applying.

For the sake of completeness we give below a formulafor a variety of emulsified wax, but we do not think youwill be able to make this, on account of the scarcity ofthe materials :

Carnauba wax, 87 parts.Stearic acid, so parts.Triethanolamine, 4 parts.Water, 400 parts.

Heat the water, stearic acid and trirthanolamine toboiling 'Point until the stearic acid has completelymelted and a smooth soapy solution is obtained.

In a separate vessel melt gently the carnauba wax.Then pour the molten carnauba wax in a very slowstream into the boiling solution prepared in the abovemanner. The solution should, if possible, be stirredmechanically at a high speed.

Motor ResistanceT HAVE a aiov. D.C. t/ie h.p. electric motor,'1- which I would like to operate on zoo v. D.C.Would this be possible by using a resistance ?

Also could you please give me details how toconstruct a resistance for varying the speed as

Resistance switching for aD.C. moor.

much as possible of either the above motor, or a`200-230 v. D.C. or A.C. one.-R. Santilli (London,W).

WE do not advise running the motor in series with aresistance from- the 200 volt mains unless the

field coils of the motor are connected in series with itsarmature. In this case" and assuming the motor hasabout zo commutator segments or more, you could usea series resistance of 45 ohms which is capable ofcarrying 1.8 amps. For this purpose you could use21 feet of 31 s.w.g. ferry wire. The speed of a seriesmotor normally rises considerably on reduced load,and the series resistance will still further increase thistendency, so it is not advisable to run the motorunloaded. .

The amount of speed variation obtainable with agiven resistance will depend on the load against whichthe motor is operated. For example, against full loadtorque the motor would run at approximately onethird of its normal speed if you use double the length

'of ferry wire in series. This wire could be mountedon a suitable former capable of withstanding 200 deg.C.,one half of this wire being tapped at various pointsand connected to a speed control switch.

Making Papier MdcheWILL you please give me instructions on how

to make papier inAche-A. G. Smith (NewMilton).

THE following are the ingredients necessary tomake a lump, of papier macho a little larger

than an ordinary baseball and weighing 17 ounces:

Wet paper pulp, dry paper, I ounce ; water, 3 ounces4 ounces (avoirdupois) ; dry plaster Paris, 8 ounces(avoirdupois) ; hot glue, a gill, or 4l tablespoonfuls.

While the paper pulp is being prepared, melt somebest Irish glue and make it of the same thickness andgeneral consistency as that used by cabinet makers.On taking the paper pulp from the water squeezeit gently, but do not try to dry it. Put in a bowl, addabout 3 teaspoonfuls of hot glue and stir the mass upinto a soft and very sticky paste. Add the plasterof Paris and mix thoroughly. By the time about 3ounces of the plaster have been used, the mass is sodry and thick that it can hardly be worked. Add theremainder of the glue, work it up again until it becomessticky once more, and then add the remainder of theplaster.

Squeeze it vigorously through the fingers to thoroughlymix the mass, and work it until free from lumps,finely kneaded and sticky enough to adhere to thesurface of a planed board. If it is too dry to stickfast add a few drops of either glue or water and workit up again. When the paper pulp is poor and themacha is anclined to be lumpy, lay the mass upon asmooth board, take a hammer and pound it hard togrind it up fine.

If the papier macho is not sticky enough to adherefirmly to whatever it is rubbed upon it is a failure andrequires more glue. In using it the mass should bekept in a lump and used as soon as possible after making.Keep the surface of the lump moist by means of a wetcloth laid over it, otherwise the surface will dry rapidly.If it is to be kept overnight or longer, wrap it up inseveral thicknesses of wet cotton doth and put underan inverted bowl. If. it is desired to keep a lumpfor a week, to use daily, add a few drops of glycerinewhen making, so that it will dry more slowly.

Wood Sections,for Microscope SlidesT SHOULD like to know how to make sections

of' wood suitable to be viewed under a micro-scope. I have made sections of stems, etc., butunderstand that this it difficult, and requiresa special technique. I have found in the pastthat these so-called " difficult techniques " are'quite practicable with sufficient patience andperseverance.-J. K. Page (Guildford).'THIN sections of the various timbers for microscope

slide preparation are generally cut dry," it beingfound that this method best preserves the originalnature, characteristics and appearances of the wood.

For the preparation of the thinnest of wood sections,a microtome is necessary. You can obtain such aninstrument for the work indicated from Messrs. Flattersand Garnet, Limited., Oxford Road, Manchester, 13.Microtomes are usually rather expensive.

It is quite possible, however, to cut timber sectionsof medium thinness by means of an ordinary sharprazor, the fragment of wood being held tightly betweenthe thumb and fingers of the left hand and the razorbeing operated by the right hand. A good deal ofpractice is necessary here, and before undertakingthe job it would be advisable to soak the fragment oftimber in spirit for about half an hour. This softensthe tissues somewhat and causes them to swell, so thatthe actual cutting is made rather easier. Neverthelessfor very accurate work, the timber sections shouldinvariably be cut " dry."

Fuller's Earth for FilteringrOULD you give me some information on- fuller's earth for filtering lubricating oil?How is it prepared for filtering ? Is it a practicalproposition for quantities of too -15o gallons ?-H. W. Lloyd (Cardiff).FULLER'S earth is merely a species of dried clay

with or without admixture of a certain proportionof dried siliceous matter, such as groundrock. InEngland the fuller's earth, as ordinarily marketed,is -a dried clay which is naturally ,contaminated with acertain amount of limestone. It has a greyish appear-ance, and it possesses a large capacity for absorption.Hence its use as a stain -removing material, and as afiltering substance.

The " earth " is quite cheap, and can usually beobtained from any paint stores. If not, inquire fromany firm of chemical suppliers and/or drysaltersyour district. In small amounts, the stuff will costyou up to 6d. per lb., but purchased in large quantities,it would, of course, be much cheaper.

It would be quite practicable to filter lubricating oilthrough a 'bed of fuller's earth and thus to rid the oilof its impurities, but the speed, efficiency and con-venience with which this could be done in any particular

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case would be governed by the viscosity of the oil,the degree of its contamination, the temperature ofthe oil, and the quantity of fuller's earth in the filteringbed. Hence, from the particulars which you give us,we cannot say definitely whether you would find it apractical proposition to filter up to r50 gallons of oil.

You will have to make experiments yourself todetermine this question. A 6 -in. layer' of fuller's earthshould give adequate filtration. Possibly, you willhave to " open out " the fuller's earth by admixturewith it of up to 25 per cent. of its weight of clean,sharp sand, otherwise the fuller's earth may become" caked," and thus refuse to filter.

Begin your experiments by using a pound of fuller'searth in a small canister and filtering the oil throughthis.

In nearly every instance, the speedy filtration of oilrequires the assistance of pressure to speed up thefiltration. Mere slow percolation of the oil through afilter bed, whilst effective, is not satisfactory forcommercial usage.

Checking Field Coils of D.C. MotorsT SHALL be glad if you can give me any informs -A tion on checking field coils of 220 v. D.C.series motors when in position.-E. A. Jenkins(Neath).WE think the simplest way of checking the field

coils of series D.C. motors in position, is tocompare the voltage drop across each coil by means of alow reading voltmeter when a constant current isflowing through the coils. If one coil shows anappreciably lower voltage across its ends than do theother coils, this is an indication that the coil is shortcircuited. The required constant current of about50 to too per cent. of normal full load current couldperhaps be obtained by running the motor on aconstant load. If not, it may be obtained by short-circuiting the armature, and feeding the series fieldcoils from the mains, or even from a battery ofaccumulators, in series with a regulating resistance forcurrent control.

Silvering Lamp BulbsCOULD you. give me details of how to silver

electric lamps, to act as a reflector ? I wishto use this type of lamp in an episcope.-T.McGeough (Newry).WE are not perfectly clear from your query as to

the exact manner in which you wish to silveryour electric lamps, but we presume that you wishto silver merely a portion of the outside of the glassbulb so that this will act, in part, as a reflector.

The job is not an easy one, and, for success, itdemands some practice. However, you may proceedin the following manner :

Make up the following solutions :Solution A.-Dissolve 6o grains of silver nitrate inoz. of distilled water and pour this solution into a

boiling solution of 48 grains of Rochelle salt in abouta oz. of water. On cooling, filter the resulting liquidand make'it up with distilled water to a total volume of12 fluid ounces.

Solution B.-Dissolve 6o grains of silver nitrate ina oz. of distilled water, and then add strong ammoniadrop by drop until the copious white precipitatewhich is first formed has nearly (but not quite) dissolved,leaving a slightly cloudy liquid. Then make the solutionup with distilled water to 12 fluid ounces, as in solutionA.

To perfonn the silvering operation, mix equalvolumes of solutions A and B, and hold down into themixed solution the lamp whose glass bulb is to be silveredon the one side. The silvering operation will takeabout three minutes, after which the lamp is gentlyrinsed in water and then dried.

The most scrupulous cleanliness must he observedduring the whole of the silvering operations. Allvessels and dishes used for making up the solutions,and for the silvering itself, must be well cleaned outbeforehand, preferably with nitric acid. This applies,also to the lamp glass itself. If the slightest trace ofdirt is present, the layer of silver will not adhere to theglass.

The mixed solutions rapidly deteriorate and onlykeep good for half -an -hour or so, but the separatesolutions will remain in good condition for a fewweeks, provided that they are kept in the dark and, ofcourse, in perfectly clean bottles.

Chromium PlatingWOULD you please give me the answer to the

following queries :Can I run a small chromium plating vat by

a tz-volt So -amp. accumulator, and, if so, whatresistance would be required

Can I get the necessary salts anywhere inLondon which only require mixing with water,and what metal would be used as the anode ?

What means is there of testing the solutionto keep it up to the correct strength ?

Can chromium be deposited direct on to brassor copper ?-W. F. Wiltshire (Romford).

THE following is a good formula for chromiumplating salt :

Chromic acid, 55 ozs.Sulphuric acid, 0.55 oz.Water, I gallon.

Operate the above bath at 40 deg. C. (too deg. F.),using anodes of lead, or, better still, of lead containing6 per cent. of antimony (antimonial lead), this alloyhaving a better resistance to attack. The liquid shouldhe maintained in a glass vessel or one of antimoniallead.

Bright deposits of chromium require from 120 to150 amps. per' sq. ft. of surface under plating. Hence,unless you are plating fairly small surface; your8o -amp. accumulator will not supply a sufficientlyheavy current. An e.m.f. of 4 volts is ample.

In wiring up, connect the bath electrodes, accnmu-lator, voltmeter and small variable resistance in series,with the ammeter in parallel.

Chromium- is by no means an easy metal to plate.It necessitates a heavy amperage. It is best depositedon nickel, but it can be satisfactorily plated direct onbrass or copper.

There is no simple way of testing for solution strengthof the electrolyte. Your best plan is to make furtheradditions of chromic acid from time to time, but theseadditions should only be very few unless the bath isbeing continually worked.

You can procure the above materials from thefollowing firms : Messrs. Baird and Tatlock (London),Ltd., 14-17, St. Cross.Street, Hatton Garden, E.C.t ;Messrs. Griffin and Tatlock, Ltd., Kemble Street,Kingsway, W.C.2 ; Messrs. A. Gallenkamp and Co.,Ltd.,17-29, Sun Street, Finsbury Square, E.C.z.

W believe, however, that a special chromium -plating salt is obtainable from Messrs. \V. Canningand Co., Ltd., Great Hampton Street, Birmingham, 18,although whether this is supplied only to the tradewe do not know.

In this latter event you might find that the followingfirm would be willing to assist you with materials :Chromium Portable Plater Sales Co., Ltd., 169-173Hampstead Road, N.W.a.

Reversing an A.C./D.C. MotorT HAVE a small A.C. D.C. 200-260 volts, 6 amps.,A - electric motor, which I am now operatingwith alternating current.

Is there any method by which I can repeatedly

411.

FieldCoi/s

ReversingSwitch

Switching circuit for reversing the direction ofrotation of an A.C.D.C. motor.

keep reversing the direction of rotation of themotor, " at the touch of a switch," without havingto dismantle the motor, except for any primaryadjustment ?-R. K. Preston (Ulverston).THE motor is evidently a series machine and can,

therefore, be reversed by reversing the currentthrough the armature. We presume you will allow themotor to slow down before starting up in the reversedirection. A double -pole two-way switch could be ,used to reverse the connections to the armature, asindicated in the sketch. A small ironclad switch wouldbe suitable. If the brushes are not fitted in the neutralposition, you may find the motor runs better in onedirection than the other. Should this prove a seriousdisadvantage, it may be possible to move 'the wholeof the brushes forward slightly in the same directionas the original rotation. We suggest about 16 deg.movement for a 2 -pole motor or about 8 deg. for a4 -pole one.

Slackening -Rusty NutsCAN you suggest anything to cut the rust of

nuts that are seized up ? I have triedRustol and penetrating oil but these work tooslow on the nuts.-J. Huggins (Enniskillen).YOU can make an excellent penetrating oil by

mixing approximately equal parts of paraffin oiland methyl salicylate (oil of wintergreen) to, which alittle ordinary lubricating oil-or, better still, colloidalgraphite-has been added.

This penetrating liquid will loosen the tightest ofnuts, but it takes time to do so, usually about fiveminutes to zo minutes. There is no penetrating oilor other substance which is capable of looseningrusted -up nuts instantly. In all cases it is verynecessary to give the liquid time to seep down into thefinest crevices.

The alternative way of tackling the problem ofloosening the bound nuts is to apply heat to them inone form or another, whereby the nuts or the boltwill expand. This expansion will proceed at anunequal rate (relative to the surroundings of the nutor bolt) and the resultant effect will be a loosening ofthe parts. A red-hot iron may be used to apply heatto a bolt shaft or to a nut.

Electro PlatingT AM trying to do a little electro-plating, in.1, an amateur way. For the battery I havemade up three Daniell cells. I can only get thediluted sulphuric acid 1.250 for the cells ; isthis strong enough ? The cells only register.75 volts and I understand they should be justover a volt. When I tried to copper -plate some thinsteel sheet the deposit was a copper -colouredjelly -like substance which could be wiped off witha rag. The surface then appeared a dull silvercolour which easily rusted. Can you say whatwas wrong ? Where could I get a nickel anodeand salts for nickel plating ?-H. Comins(Oldham).

THEORETICALLY, a Daniell cell should give justovert volt, but, in practice, the e.m.f. of the cell

hardly reaches t volt. The fact that your Daniellcells only register 0.75 volt points to some internalresistance in the cells. If you can eradicate this,then the e.m.f. will increase accordingly. However,for plating purposes an e.m.f. of 0.75 volt is quitesatisfactory.

The sulphuric acid which you are using is suitable.If, however, you wish to procure the concentratedacid and to dilute it yourself, this acid can be obtainedin small amounts (on persona! call) from Messrs. J. W.Towers, Chapel Street, Safford (near to Victoria Bridge),Manchester.

Without knowing the composition of your platingsolution, we are afraid that we cannot express a trueopinion as to the cause of its failure to give satisfactoryresults. Assuming, however, that the solution isapproximately correct in composition, it looks asthough you are using too heavy a current.

The following are two good formulafor copperplating, the cyanide formula being rather the better :

Acid copper plating.Copper sulphate, 27 ozs.Sulphuric acid, conc., 7 ozs.Water, t gallon.

Use at temperature of 75 deg. F. Brass or coppermode. 0.75 tot volt e.m.f.

Cyanide copper plating.Copper carbonate, 5 ozs.Sodium cyanide, to ozs.Photographer's " hypo," 64 oz.Water, t gallon.

Use at temperature of too to Ho deg. F. 0.75 to2 volts e.m.f. Copper anode.

Copper and nickel -plating salts can be obtainedfrom any of the following firms : Messrs. W. Canningand Co., Ltd., Great Hampton Street, Birmingham, 18 ;Messrs. R. Cruickshank, Ltd., Camden Street, Birming-ham, t

'Messrs. Johnson, Matthay and Co., Ltd,.

Hatton Garden, London, E.C.Any of these firms (particularly the latter) should

be able to supply you with a strip of pure nickel toact as an anode.

Electron RadiationTS there any method of producing a flow ofI electrons other than in a gas -filled orevacuated glass envelope (such as a cathode-raytube), and, if so, is there any physical danger ?I believe I have seen it stated that if ultra -violetlight is directed on to a zinc plate electrons areliberated. I, do not wish to use ultra -violet ifyou can suggest a better method, but how canultra -violet be produced safely, and does thezinc deteriorate ?

Are there any fluorescent substances which arepermanent in air which can be procured by theamateur cheaply.-R. H. Norton Dawson(Hampstead).

ELECTRONS are evolved from any heated body.The higher the temperature of the heated body

the more intense the electron flow. Thus, an ordinaryred-hot wire evolves electrons freely.

When certain wavelengths of light fall upon metalsthey liberate electrons. It is quite true that electronsare liberated from a clean zinc surface when ultra-violet rays fall upon it, this action forming the principleof one type of photo -electric cell. The zinc, or othermetal which acts as an electron -liberator, does notdeteriorate. As a source of ultra -violet rays you canuse either a carbon arc or a mercury -vapour lamp,both unscreened by glass.

Before commencing any experiments we wouldstrongly advise you to read up any modern bookson light, television and allied subjects which may beavailable in your nearest .library, since the liberationof electrons (and their subsequent direction andutilisation) is not such an easy matter as you seem tothink. There is no danger connected with an ordinaryelectron flow in the sense which you infer.

By your use of the term " fluorescent " do youstrictly mean " fluorescent," or do you mean " lumines-cent ? " In other words, do you refer to a materialwhich glows under the influence of ultra -violet light, ordo you imply a material which is luminous in thedark ? Solutions of eosin, fluorescein and acriflavinare fluorescent. Ordinary vaseline or petroleum jellyis fluorescent, as are many mineral oils. Luminescentmaterials are barium, strontium, calcium and zincsulphides. In our experience, the best of these is" luminescent zinc sulphide," which is procurable,price about 3s. per oz., from any large firm of laboratorysuppliers, such as The British Drughouses. Ltd..Graham Street, City Road, N.t.


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May, 1945 THE CYCLIST 57

6titfat

VOL. X111

THE

Editor : F. J. CAMM

MAY, 1945

wit' d )

No. 279

Comments of the Month

All letters should be addressed tothe Editor, " THE CYCLIST,"

eorge Netvnes, Ltd., Tower House,Southampton Street,Strand, London,

W.C.2.Phone : Temple Bar 4363

Telegrams : Newnes, Rand, London

The Interim ReportTHE Interim Report of the Committee on

Road Safety has just been published.The committee consisted of five members ofthe Ministry, of War Transport, one memberof the Home Office, one member of theMinistry of Education, one member ofthe Ministry of Information, one member of theScottish Home Department, three membersrepresenting the police, and five membersrepresenting the Royal Society fcr thePrevention of Accidents.

The report is in some respects a tendentiousand minatory document. It points theaccusing finger, when it should be mainlyconcerned with finding causes and cures. Itblames road users for accidents. It is notedthat there was not a member of the public onthe committee to give the public point ofview. It would appear from this documentthat the M.O.W.T. does not lay any blameat its own door for failing to make the roadsconform to modern tendencies and progress.It forgets that the Road Fund was introducedby Lloyd George for the specific purpose ofmaking new roads and improving old ones.

The Chancellors of the Exchequer duringthe past twenty years have successively rifledthe Fund to balance the Budget and adoptedmethods which in ordinary business wouldhave landed them in the dock, for mis-appropriation of public funds is an offence.If a tax is imposed for a specific object, andan assurance given by the Prime Minister ofthe day that the Fund would not be used forany other purpose, we maintain that that ismisappropriation.

The Ministry of War Transport havingfailed to bring the roads up to date now seeksto blame road users because road travel isexpanding beyond their own road plans. Itthreatens further legislation and blames thepublic for its own ineptitude. It thinks thatthe accident problem can be solved by im-proved methods of propaganda, and byimposing fines. These methods have beentried before and failed.

The principal recommendations are thatresponsibility for road safety measures shouldbe shared by local authorities, that remedialmethods should be adopted quickly (whatremedial measures ?), propaganda must beconsistent and continuous and directed to alltypes and ages of road users, the HighwayCode should .be the basis of all propagandaand that it should be revised, local safetyorganisations should be set up in all localauthority areas, the support of the Press andthe B.B.C. should be sought, approvedexpenditure incurred by local authorities onlocal road safety should rank for Governmentgrant, roadside advice should be given by thepolice, a universal speed limit should not beimposed, and the aosanile limit should beapplied with discretion.

Driving tests for applicants suffering fromdiseases or physical disabilities should bereintroduced immediately, driving tests shouldbe made more searc4ing, control of the returnof traffic to the roads should be effected bymeans of a basic ration of petrol for private

motoring for a short period, cyclists shouldbe required to report accidents in which theyare involved, and massed -start cycle racing is" undesirable."

The report goes on to suggest that had orinadequate road conditions should be remediedby vigorous action. Those responsible forthe planning of roads and their layout and fortown and country planning should have regardto the principles of segregation of traffic andclasses of traffic, traffic signs and signalsshould be improved, the parking of vehiclesin busy streets should be prohibited andadequate parking spaces should be provided.

Surely, the Ministry of War Transportunderstands by now that cars are parked inbusy streets because there are not adequateparking places, nor a sufficient number ofgarages. The London County Council hasfor years opposed the construction of garagesin London. The police have opposed publicparking places.

We do not agree with the report when itsuggests that accident investigation and reviewshould be undertaken by the police, and theengineers of the Department and Highway of racing.'Authorities. The police have shown a markedpartiality in their reports in the past, and havelargely relied upon third -hand evidence.After supporting the Alness Report on someaspects of road safety, and disagreeing withit on others, the report goes on to state thatthere should be intensive research with regardto vehicle lights and the prevention of dazzle.

The main clauses affecting cycles andcyclists are : That pedal cycles should havetwo efficient brakes, cyclists should becompelled to carry bells on their machines,cycles should carry a red rear light at night inaddition to a red rear reflector and whitepatch (now law), the provisions of the RoadTraffic Act, 1934, with regard to the carriageof passengers on pedal cycles should beclarified, and pedal cycles should be required to conform to a standard of fitness.

The Alness Committee stated that theyrealised early in their deliberations that thereis no single or sovereign remedy for thesolution of the problem submitted to them.They also appreciated that the remedies tobe recommended by them would have to be,if not dramatic, at any rate drastic in theircharacter, having regard not only to theexisting magnitude of the evil but also to thesteady annual increase of motor vehicleson the roads. In other words, thoughthey were satisfied that there is no panaceafor the mischief, they must seek, and ifpossible find, a long-range policy.

We shall deal in later issues with thisreport in detail.

Massed -start Racing

THE report states : " We understand that,despite the action taken by the Ministry

of War Transport and the Home Office todiscourage this form of cycle racing on thehighway, an attempt is being made by onebody of cyclists (the B.L.R.C.) to populariseit. At present the roads are comparatively

By F. J. C.

free from congestion, and massed -start cycleracing is not, therefore, open to such strongobjection as would be the case in peacetime.But there is little doubt that it is the desireof those responsible for encouraging this formcif cycle racing to introduce it on a scale andon lines comparable with similar racing onthe Continent.

" We are clear that massed -start racing, asdistinct from time trials, is likely to give riseto danger both to those participating in theevents and to other road users, and werecommend that if the efforts of the Depart-ments concerned to discourage this form ofracing do not achieve the desired results,consideration should be given to the introduc-tion of stronger measures. At the presenttime no legal offence is committed by holdingmassed -start races on the highway unlessobstruction or danger is caused to other roadusers. The police have been recommendedby the Home Office to watch these activitieswith special care and we support this recom-mendation as we view with apprehension anyextensive use of the highway for this type

The police have been watching this typeof racing with special care and have expressedtheir views in favour of it. The onlyapprehension which this particular committeefeels is the apprehension raised by two rivalbodies-the N.C.U. and the R.T.T.C. Itwas admitted to us by the M.O.W.T. that theonly letters of complaint they had receivedhad been from these two bodies, who areobviously concerned to see that a form ofsport likely to prove more popular thantrack racing and time trials (indeed evenduring the war it has proved more popular)was killed at birth. The view of the com-mittee therefore on massed -start "racing-aview expressed without hearing the B.L.R.C.side of the question-is one which does notcarry weight.

We can assure the M.O.W.T. that massed -start racing will continue and any movetowards legislation to make it illegal will befiercely contested in Parliament itself. Wecannot accept the position that the N.C.U.,the R.T.T.C. and a few northern members ofthe C.T.C. are to decide the future of cyclesport, nor can we accept the view that50,000 members of these bodies are entitledto impose their will on so million cyclists,for whom they falsely claim to speak.

We ask the committee : Who was responsiblefor prompting it to include in its report theabove statement against massed -start racing ?What gave rise to their " apprehension " ?Was it the chain rattling of the N.C.U. ? Wasthe N.C.U. represented on the committee ?

Note to C.T.C. Members

WE invite C.T.C. and N.C.U. members towrite to us stating whether they are,

or are not, in favour of rear lights. We areconducting this referendum in the interests ofstatistical accuracy. We want to find outwhether these bodies can justly claim tospeak for 50,000 cyclists.

58 THE CYCLIST May, 1945

=

eTiihOps Tawton.--, 1 ,roiSouthgate PromotionRS. PHILPOTT, Southgate C.C., has been

promoted major. He is in the Indian Army andis holder of several club long-distance records.

Westerley Champion KilledTHE Westerley Road Club champion of

Sgt. G. Strong, has been killed in aaccident. He was serving in the R.A.F.

Garside's DecorationDETTY OFFICER THOMAS GARSIDE,-I- Road Club, has been awarded the D.S.M.

Local Appreciation

xo4x,flying

Beds

RESIDENTS of the Gartcosh district of Glasgowsubscribed kioo as a token of esteem and good

Wishes for Pilot Officer W. Hendry, third member ofthe famous Clydeside time-trialists, to commemoratehis award of the D.F.M.

Southgate DecorationCPL.J. GRAHAM, Southgate C.C., has been

awarded the Military Medal for bravery in Italy.

News of PurvesTT is believed that James Purees, pre-war Vegetarian.L C. and A.C. stalwart, who was twice captured as aprisoner of war, has been released from an UpperSilesian coal mine where he was working.

Addiscombe LossesKCOX, Addiscombe C.C., has died of wounds

sustained in fighting in France, and Isis club mate,L. Martin, is now presumed lost at sea following enemyaction some weeks ago.

Clubmen Casualties0 S.M. F. BAILEY, Manchester Wheelers ; Cprl.

. J. Hanson, Huddersfield Road Club ; J. PickfordSouth Lancs. Road Club, and S. A. Orrell, NorwoodParagon C.C. are included in the ever-growing listof clubmen Who have made the supreme sacrifice.

DecoratedL 0. HARRISON, North Road C.C., has been

awarded the D.F.M.

Special Air ServiceF. VALENTINE, Southgate C.C., who was doing

i. . some prolific rides two years ago, s now a ;sergeantin the Special Air Service. He saw active servicebehind the lines after " D Day.

Club RevivedTHE Ilford Road Club is to be'reyived. Since the

outbreak of war a skeleton committee has dotiOits best to maintain contact with the Many servingmembers.

Dukinfield JubileeDUKINFIELD C.C. celebrates its diamond

jubilee this year.

Trader's IllnessGT. ROBERTS, hon. sec. London Branch of the

National Association of Cycle Traders, is ill andhas resigned office.

. A . ChairmanAA J. BRADBURY, ptesident

of the Manchester Wheelers,has been elected chairman, forthe_third consecutive yearAif theNational Association of CycleTraders, of which he is alsopresident.

Bevin Boys

FLOVE, Southgate C.C.. R. Dickson, Carluke C.C.,

and N. McKendrick, GoldberryC.C., are among those who havebeen directed to work in themines.

Activity in IndiaEHALL, Sittingbourne C.C.,

is serving in India, wherehe has ridden in several events.

Oxford City's LosspLYING OFFICER-L. LEONARD KING, D.F.C.,Oxford City Road Club, hasbeen killed in action.

Rotherham WheelersCelebrate

RO'T'HERHAM Wheelers havecelebrated their 25th

anniversary.

A. J. Wilson DiesTHE death has taken place of A. J. Wilson, the

famous old-time cyclist. He was 87.

Dunlop SportsDUNLOP sports will be held at Fort Dunlop,

Birmingham, on Saturday, June 3oth.

Yiewsley Road Club AwardsTWO members of the Yiewsley Road Club have

received the D.F.C., the latest recipient beingW. E. G Thorby.

F.10. P. Watkins, D.F.C.O. P. AVATKINS, De Laune C.C., has been

. awarded the D.E.C.

Morrison InjuredPLIGHT SERGEANT' DONALD MORRISON,

D.F.C., Glasgow Wheelers, has been seriouslyinjured in a road accident.

Phoenix PedallersT'llE latest Forces cycling club is the. Phoenix

Pedallers, which has been formed among cyclistsin Ceylon.

Crook WheelersACOUNTY Durham club, the Crook Wheelers,

is being, re-formed.

N.C.U.-LossesADEVONPORT, popular ifficial of the N.c.tr.,

London Centre, has ,died in France as the resultof an accident. He was serving with the ForceS. Acolleague, F./O. L. Claydon, is known to be a prisonerof war.

Kentish Wheeler DecoratedPILOT OFFICER C. MANSFIELD, Kentish

Wheelers, has been awarded the D.F.M. forgallantry during flights over the Danube and Rumania.

Calleva's RecordTWENTY-SIX members of the Calleva Road Club

are serving with the Forces ; four have made thesupreme sacrifice.

Grantham's Coming of AgeGRANTHAM Road Club this year :celebrate their

coming of age.

St. Christopher's LossBRITTAIN, prominent member of the St." Chrfstopher (Leeds) C.C., has been killed in

action. He was serving in the R.A.F. and lost hislife while in action in Burma.

Pilot Officer's ReturnPI LOT OFFICER F. W. BATTERBURY, well-

known South London clubman, who was reportedmissing from air operations last year, has returnedto this country.

Speedy BoysPOST Office telegraph messenger boys have formed

their own cycling club in Portsmouth. With amembership of almost 4o it is known as the TelegraphMessengers' C.C.

Ray Peebles WoundedRAY PEEBLES, Wolverhampton Wanderers, has

been wounded while serving in North-WestEurope.

H. T. Franklin DiesHT. FRANKLIN, founder member of the Victoriar C.C. and former official of the Eastern Counties

Cycling Association, has died at his home in SouthDevon.

EnthusiasmLANCE -SERGEANT R. ELLIS, Highgate C.C.,

who is a prisoner of war in Germany, has starteda series of lectures on cycling in the camp where he isinterned. He is not the only club cyclist in the campas he has met, among others, Fred Johnson, MonctonC.C., A. Hunt, Stretford Wheelers, and Jack Read,Birkenhead North End C.C.

A et* itN.fry.4v4-*

C U MOSSFifesItire

The looly market' crQSSSurrounded by many pick4t14 irderestans buildings


Around the Wheelworld

A. J. Wilson Passes

ONE who can rightly claim to have beenthe W. G. Grace of cycling, namely,

A. J. Wilson, known to readers of cyclingliterature as " Faed," died on Tuesday,March 20th, at the age of 87, after a longillness.

Born on February 17th, 1858, Arthur JamesWilson can justly claim to be one of thefew who founded the sport and the pastime,for he was associated, not only with thesport, but also with the industry and thecycling Press.

Although he suffered, from the age of 12,from the affliction of deafness (hence hispen -name of " Faed "), he dill not allow thisto interfere with his racing and businesscareer. In his early days he was keen on thetricycle, having for some time previouslydistinguished himself on the Ordinary.He was trained as an engraver, being employedin the manufacture of woodcuts for illustrationpurposes.

His main successes were on the tandemtricycle, the Sociable, and the tricycle, onwhich from 187o, when he was only 12, hecommenced to race. It was in 1880 that heformed a club for tricyclist-the NorthLondon Tricycle Club, later, the N.L.C.C.It was under the badge of the club that hedid most of his early racing, and early in hiscareer he took to the cinder track and hillclimbing. He raced on the Sociable at theAlexandra Palace track, and rode againstsome of the stalwarts of the day, includingR. J. Mecredy (Arjay). In those days openroad events were unknown so " Faed "formed the North Road C.C. to promote roadracessih which the best riders from other clubscould compete. He was the first presidentof the N.R.C.C. and he rode in its first fiftyon June r9th, 1886, an event which he wonwith C. E. Lyles on a tandem tricycle in3 hrs. 16 min. 28 sec., a figure which heheat on September 22nd, 1886, with G. P.Mills this time as the partner, in 2 hrs. 46min. 3 sec.

In 189t he covered 164.1 miles in 12 hourswith J. J. MacCarthy on the tandem tricycle.At this time the N.C.U., cowering before thedirty attitude of the police force of the time,who were kotowing to the horse-drawnvehicle brigade and prosecuting cyclists onthe flimsiest pretext, had thrdwn road sportoverboard. I have already quoted the famousresolution of March 8th, 1888, made by E.Hecht, which requested clubs to refrain fromholding road races, precluded N.C.U. offi-cials from assisting in them, and withdrewN.C.U. homologation of road records.

We see to -day the N.C.U. making the samemistake in connection with massed -startracing: However, Hecht's proposition wascarried by 63 votes to IS, so Wilson promptlyresigned his position as timekeeper, andformed the Road Records Association, ofwhich he became first president, a positionhe retained for many years.

He wrote a vast amount of matter concerningcycles and cycling, and in 1879 he joined thestaff of Bicycling News, the oldest cyclingjournal in the world and of which the presentwriter was the most recent Editor. He becameits Editor and later joined Lacey Hillier inpromoting the lively journal, Wheel World.He joined Mecredy in 1889 in Dublin tostart the Irish Cyclist, and it was during thisperiod that he met Dunlop and the Ducrosbrothers in connection with the Dunlop tyrewhich was just coming on to the market.

Wilson became the London Business

By ICARUS

Manager of the Dunlop Company, and laterPublicity Manager. He then founded thefirm of A. J. Wilson and Co., which handledthe Dunlop Publicity until 1928.

His cycling books are still much ' soughtafter and include Riding Rhymes, theChronicles of Duffersville, Two Trips to theEmerald Isle, and many others, which fortu-nately grace my bookshelves. I have readand re -read them many times.

He founded the Cycle Trades BenevolentFund, and was a frequent contributor to this,journal. His passing will be regretted by avast circle of those who knew him, and of hisinfluence on the trade and pastime. Amemorial service took place at Holy TrinityChurch, Marylebone, on April loth.

A Cyclist's ViewsAPROPOS our Leader last month on the

subject of rear lights, I have receivedthe following letter from Mr. F. Selwin, ofFinsbury Park, N.4:

"As a new reader of your publicationPRACTICAL MECHANICS and with itTHE CYCLIST may I congratulate you onyour leading article in CYCLIST under" Rear Light Bill Passed," and crave spaceto have this letter published ? The broadoutlook and common sense in Your leader,and the paragraph titled " Hig " by Icarusare a real pleasure to read.

I am urged to write this letter becauseboth as a citizen and as a road user, pedes-trian, cyclist, motorist, and motor cyclist,I am appalled at the magnitude of the roadcasualty figures, at a time when none butessential (?) vehicles are on the roads, andseriously interested in anything which willhelp to increase road safety for all.

To find such statements as made by Mr.F. J. Urry under the paragraph " Rear Lights"on the pages following your leader and thepage by Icarus, is disconcerting.

I would contend that statement, and refutethe remark about eyesight, as I have beenmedically examined three times in the pastthree years, and passed fit not only to hold adriving licence, but to carry out operationalflying duties. Such thoughtless remarks asthese do the author no good, nor do theybenefit his cause. Mr. Urry has evidently nothad the horror, as I have, of sitting at theroadside, while a friend died in his arms asthe result of a collision with the back of anunlit lorry. I would strongly urge Mr. Urryto stand at the gates of any large factory, andnote the numbers of clean white patches andefficient reflectors he sees coming out. Betterstill to mount a real cycle and follow anyarterial road after dark when the roads carrycrowds of people returning home either at theweek -end or during the week, when dis-courteous motorists with both headlightsblazing dazzle the oncoming traffic. Atsuch times a rear light well placed is not anadvertisement, it is an insurance policyagainst- accident. No one insures becausethey want to get hurt or killed, they insurebecause they feel they are covered if anythingshould happen. Has Mr. Urry ever thoughtto ask himself another question : " What isit that you can see best on the road on afoggy night, when sensible people ride ordrive on pilot or side lights ? ' Is it not thered rear light shining from the invisiblevehicle in front ? Finally, it isn't everymotorist or motor cyclist who uses " the fullpower of his headlights " all the time."

The Cambrae RaceFOR the information of the Ministry of

War Transport here is a quotation fromthe entry form issued by the Clarion whoorganised the Cambrae Road Race, and finallyran it on lines exactly similar to B.L.R.C.rules : " Although the roads are closed com-petitors should not assume that they will beclear. Always be prepared for an emergency.Remember the promotors are not responsiblefor damage which may be suffered bycompetitors or spectators." It is clear theroads were not closed.

Yet this race was supposed to have beenrun under N.C.U. rules which do not permitraces on roads not closed to the public.The simple answer, of course, is that theN.C.U. knows perfectly well that it has nopowers, nor has the local authority the power,to close the roads for racing.

The B.L.R.C. has issued a statement ofpolicy in which it repeats that it exists toencourage and promote in Great Britain allforms of amateur and professional cycling,based upon international practice and inconformity with U.C.I. rules. Copies of thepamphlet are obtainable from J. Kain (thenational hon. secretary), 24, Disraeli Road,London, W.5.

British " Best -all-round " Competition

AQUESTION has been put to the R.T.T.C.regarding the application of Condition

12 of the Competition (page 54 of the Council'shandbook) to the case of a rider who changeshis club.

In order to remove any uncertainty whichmay exist in the minds of riders, it is desiredto make clear that in events under the juris-diction of the Council this condition appliesonly to events which are included in thecompetition.

The performances of a rider for the purposesof the team section of the competition willnot be affected by his representing anotherclub in events which are not included inthe competition.

B.L.R.C. North-Eastern Section

THE first event Of the recently formedNorth-Eastern Section of the British

League of Racing Cyclists, which was a LowGear 25 -mile Time Trial, was held withsuccess on Sunday, March 25th, 1945. Theleading times were the fastest recorded_ inthis area for a long while for any similarevent. Out of an entry of 34 only three failed tostart. The leading timer were as follows :

Hrs. Min. Secs.I. L. Wilson, Northern Coureurs I 7 32. W. McCarthy, Northumbrian

R.R.C. 8 r3. R. Sowerby, Northern Cour-

curs.. 8 164. K. Hicks, Ridley C.C. .. I io 5o5. W. Graham, Northern Cour-

curs.. . I II 286. J. J. Pearson, Northern Cour-

eurs . . .. .. .. I II 457. F. Watson, Northumbrian

R.R.C. .. .. .. I II 468. R. Leftwitch, Northern Cour-

eurs.. .. .. .. I IIFirst handicap, W. McCarthy ;

handicap, L. Wilson.Fastest team, Northern Couriurs ; Fastest

novice, J. Hann, Northern Coureurs.

46second

60

V./ c' -h-,0

ly EcLURRY

Better. GoodsEVER since the war started and we were compelled

to carry rear lights by Order in Council, wecyclists have complained bitterly that the lamps-or somepart of them-have been so poor in quality that reliabilityof the light properly functioning was never certain.Now that rear lights are fastened on us for ever, thetime has surely arrived for a complete overhaul of themeans to carry out our liability with more certaintythan has been the case since September, 1939. Wewant better batteries, better lighting bulbs, betterlamps and lamp connections and better dynamo sets.Possibly they will cost us a trifle more in the first place,but their longer life should prove to be a considerableeconomy. The tinsel things of to -day are not goodenough for permanent wear. How bad they are as faras the battery lamp is concerned, I know from far toopractical experience. It is easy enough for the Govern-ment to tell us that rear lights on bicycles are simpleand troubleless. I wonder if such cheerful critics haveever tried to change a fractured bulb on a night ofstorm, or fix one of those flimsy connections that sooften defy rectification ? Years ago we had goodlamps ; they were made from brass sheet and riveted,and did their job with a high degree of reliability. Butthe wretched tin-plate things of to -day that rust in afog, or " short " in a shower are a nuisance and a worryto the regular rider, and our lamp makers ought toknow and correct the trouble. I see that someonerecently suggested all new bicycles should be equippedwith lighting sets ; a car is, why not a bicycle ? Notfor me ! I can and do ride many more thousands ofmiles without a lamp than with one. Why should Itravel round with three or four pounds of additionalweight for no purpose ? The motorist is not so burdenedbeing pushed about by his iron horses.

Only the Best WantedT HAVE said often enough in these columns that theA full joy of cycling can only be experienced by theowners of the very best type of bicycle. If the gistof my correspondence is any indication of the publictrend in this direction, then the truth embedded inpleasurable cycling is surely getting home. Individualsmay differ in the kind and type of specifications theyfancy, but it is remarkable how insistent they are on thequestion of quality. I wonder if this fact is reallyunderstood by the makers ? There is any amount ofmoney waiting to be spent on bicycles and their equip-ment directly first-class goods are again available ; butat the moment there is little indication of the returnof the very best to the public market. What is thesnag ? Is it lack of material or labour or a combinationof both ? I know this, that unless the trade can " get amove on " and supply the waiting thousands with thefine products it is capable of manufacturing, manycyclists will get tired of waiting and Seek other avenuesalong which to burn their leisure. And that would bea pity In letter after letter I am asked if it is yetpossible to get so-and-so ; there seems to be .morebicycles for sale but they are all of a rather sad wartimesombreness, and lack the mark of quality. I shouldhate to see the industry descend to plain utilitarianismwhich seems to be the danger our habits have beenforming during these years of war. Is it not possibleto shake them or the Government Control out of thislethargic state and so restore to themselves and us,their customers, a decent pride in the articles they makefor the pursuit of happiness ? This is not a criticismof destruction ; but an ardent desire expressed byMany ,people, _Services and civilians, for the best inbicycles with " price no object," that invariable comment.Underlined in most of my letters.

Good LuckA S a matter of fact I have 'recently ordered a new

41., bicycle because I found a maker who had a very*small stock of pre-war tubing, a pair of stainless steel

THE CYCLIST

rims and a pair of high-classbrakes. Such a rare chancewas -too good to miss, so Ipromised to see what I couldfind in the way of tyres, aspeed -gear, saddle andrubber grips. Between us,the maker and I have solvedthe shortage handicaps, andsoon I hope to be riding abicycle that may not be apost-war model, but wiltcertainly be as good as any-thing the pre-war cyclingworld could make. As thiswill be the first new bicycleI have acquired for five years,I too am not particularlyconcerned as to its cost, orthe troubles that have goneto make it a worthy exampleof what a bicycle should be :I am only too happy to feelthe thrill of bestriding a newinach:ne at a time of the yearwhen I can give it plentyof mileage exercise. Forthat simple and enjoyableexcitement of possessing anew bicycle never quite

.departs from the mental andphysical make-up of theardent rider, and thoughyour critical faculties increaseas you grow older it isseldom you find them of ser-vice when you arc trying out

' - a high-class machine madeto your pet specification and

set to your exact positioning- Let me say at oncethat I have been most fortunate in obtaining thismachine, for I know my friend the maker could notbuild another like it now, and that the pre-war open -sided tyres that will adorn it arc, I should imagine,one of the last pairs available in this Midland area.I mention these facts because so many people seem tothink I have some secret sources of supply, and couldif I would, introduce them to the happy places. As amatter of fact I should only be too glad to publicisethe supply of the good goods if I knew of them, andmost certainly shall do so directly, they are available.

A SuggestionHATE to feel all " muffled up " when riding a

and have never yet been able to seekcomfort from an overcoat of the conventional kind whenawheel. Yet the bitter weather of late January calledfor something extra than a heavy jersey, for warm asthat garment is in calm weather, the wind, with theedge of a `Abetted knife, goes through it in tiny draughtsto seek and chill the forefront of the rider. So Ibethought me of a friend who might perchance haveenough Grenfell cloth in stock to make me a light,easy -fitting windproof garment to slip into when thebitter breezes are prowling round,- and once again Iwas lucky: This coat takes up no more room in thebag than a sweater, slips over an ordinary coat, hasstorm cuffs, and a couple of big pockets to take all theoddments the average man collects, and, indeed, is areal utility garment. It has been cut about a couple ofinches longer than an ordinary lounge coat, so thereare no tails to get mixed up with mudguards or brakes,and it doesn't seem to matter how carelessly you foldit ; creases are unknown. I think it is going to be veryuseful for cool weather riding, and maybe a spare totake touring when one's ordinary light jacket can besecurely tucked away on rainy days and this over-allsubstitute given the dirtywork, as it were. The lumber,type of jacket-borrowed'from the golfers-might bequite good, but for me itlacks pocket room and allowsthe draughts to circulatefreely round that portion ofmy anatomy which is saidto be the seat of lumbago,and I don't like it. I believethere is a call for a coat ofthis type among regularriders and tourists, and I .commend the idea to ourcycling clothiers.

The Glory of theNightW A S odt for a nightp r,o w I recently when

there was no moon, but thestars were a mass of jewelson the velvet background ofthe sky. How frequentlywe say : " It's a beautifulnight outside," and leaveit at that ; yet I know fewthings more soothing than aquiet ride under the starswhen the urgency of the dayhas slowed to the occasionalswiftly passing presence of along-distance lorry, and onlythe owls and a predatory foxbarking his challenge, seemto b e alive. And thelorries: their restoredlighting has g i v en them

Finciest..t acts .

The fame Chllbeealful surroundonteThe rawer has a double rad -Saddle recq-

May, 1945

extra speed, and now they pound along at what seemsto be a terrific pace, though probably it is not so highas.we imagine for the simple reason that their noiseadds attention to their passing. That they can now seetheir way seems to me to be quite positive, for on astraight stretch of the Lcindon-Liverpool road I stayedto watch a convoy of them passing at intervals, andafter they had gone stepped out the distance from whichthe road ahead of them was clearly lit, and had disturbedthe verge -feeding rabbits, and found- it was approxi-mately 632 yards. In view of the rear -light controversy,and the many opinions expressed which so obviouslylack the backing of experience, I thought this informa-tion, on the spot as it were, May he interesting. BeforeI reached home a great covey of 'planes went over, alllit up, and made for me elude a pyrotechnic displayas the goose -flights ranged the night.; and long afterthem came a lone roamer of the skies, whose lightsmingled with the stars, and seemed almost to be oneof them which had tired of its fixity, and like She writer,wanted to roam. The silence, shot with the sibilanceof the small night noises and the quiet wind, came tome, the distant warm lights of cottage windows, andthe unmistakable scents that this old earth was thinkingof the summer to be ; and so I came home refreshedand very thankful for such simple things.

Dirty WeatherN cop way to work or home when the rain teems

down, I get -well bespattered by the passingmotors. , I have become inured to it arid seldom takeany notice ; it is part of the penalty we cyclists haveto pay as the price of our freedom, although such isnot usually considered in any regard when the argu-ments are advanced suggesting the cyclist has so verymuch for which to thank the motorist. One very dirtymorning I received most of a puddle full of mud flungover me by a very urgent car whose driver cut in,glanced back at my discomfiture, and waved his hand,whether in friendly apology or in a " serve -you -right "frame of mind I do not know. I wondered at the time,and I wonder now, what would be said of cyclists ifthey did or were capable of doing, such things tomotorists ? For it is a fact that the huge majority ofmotorists are decent in their manner of overtakingwhen the roads are bad, as I know fullwell ; but thefew thoughtless and reckless ones can make life veryunpleasant for short periods by the rude use of theirvehicles' giant strength and speed. A small point ofcomplaint, but one that bears hard on tempers whenthere is really no need for it.

Growing Old][71'

is generally agreed that when you go down hillyou go faster, but when you descend the slope

the years you go slower-but it seems faster. I arw.quitecontent that it should be so, and as it is inevitably thefact, that is just as well. l'he thought came to me somedays ago when I timed myself over the home -to -workjourney and discovered I took an average three minuteslonger than was the case immediately pre-war. Hadanyone told me the six miles of urban and town ridingneeded another half minute a mile to provide me withcomfortable going, I should not have believed it ; buttime is a fixed measure that takes no account of age.Its speed is constant, yours is not, and in the naturalorder of things cannot be. A little check up on theselines is a very good corrective for anyone, if only becauseit measures your otherwise un-noted physical declension,and suggests that growing old gracefully is one of themajor virtues for living at all. I don't know- I am slower,or that I am growing old ; I have to bring the stopwatch to prove the charge ; which is far more satis-factory to me than the thousand and one reasons manyof my friends juggle with to excuse their want ofvitality. If you ask me why my outdoor life is sohappy, I have only one reply-cycling.


*THE TEN TON BOMB has added10.000 lb. of dead weight to the. Lancasterbomb load now the greatest in the world.The bomber itself has been reconstructedfor its extra task. The entire weight ofbigger bomber and bigger bomb is carrieddown the runway on two rubber tyres-and once more Firestone takes the strain.

they use

Tirestone* Your help to meet this great demand is vital.Not one ounce of rubber, synthetic or naturalmust be wasted. Keep all tyres properly inflated. tyres


i

The glow ofhealthy exercise ... a

nip in the air tempered byearly Spring sunshine ... ahead,

the turn in the road and beyond,the distant valley : old world village. . . cosy inns .. . a cottage lunch or

wayside picnic. Cycling at its best !The turn in the road, everrevealing the unexpected, is oneof the fascinations of cycling.But it may also reveal an

unexpected emergency :be ready to

meet it.

N THEif

Remember, rain orshine,you can cyclein safety iF you Fit

ERODOAll -WeatherBrake Blocks


CYCLORAMANorthwood Cl^arcl-k

Isle of W191-rt.

A pictiare.sque little kibot olf the /5.7.5t.

beaten hack oveiloolunq theMedina aver betwe. ',impartand C..0045 . .

,,,r77 -1'1"`"'```&t,

.044;4.

Spring is is Really HereT FANCY that King Winter's reign is over,1 for to -day the sun is warm on my back,and the daffodils are all a -bloom, and thereis every sign that spring has turned the corner.And who greets the return of spring withmore ardour than the keen cyclist ? Who longsfor the sunny days more than the man who,when they come, can take his bike out andride out into the countryside ? The seasonsmean much to the cyclist, and although I aman all -the -year-round rider, and find joy andcharm in riding in October, and even inJanuary, I am glad, all the same, when Ican ride out and greet the spring. Soon . . .

and there will be meadows golden with butter-cups, and the fringes of the by-pass roadswill be aflame with dandelions.

Old Cycling JournalsT T is always good when a contributor1 receives letters from readers, and theEditor kindly sent me on a communicationrecently from Mr. G. Rodell, of Harpenden,who mentions that he remembers his fatherreceiving cycle trade journals carrying illustra-tions of cycle scouts in the Matabele War.One picture had the caption, " On the trail ofLo Benguella." Mr. Rodell's father was acycle builder, and in the early days advertisedthe " Fram " machine. He also assisted inthe manufacture of one of the earliest dynamos,made by Ferranti Thompson and Ince-thedynamo now being on exhibition in the ScienceMuseum at South Kensington. In passing,Mr. Rodell mentions that when in SouthAfrica he had a Zulu boy working for him,whom he christened " Bicycle," owing to thefact that the boy wore, through the enlargedlobe of each ear, a length of Bluemels' pump,about 4in. long ! Thank you, Mr. Rodell,

for these interestingreminiscences ! A whiffof history is a 1 way swelcome !

England's PrettiestVillage?

T T is always cropping1 up, this questionas to which Englishvillage can lay bestclaim to the title " theprettiest of all." Per-sonally, I rather deplorethis comparing ofbeautiful villages, forwe have so many whichare lovely, and, afterall, it is really a matterof tast e. There arecyclists who will toler-ate no challenge to theclaims of Kersey, inSuffolk. There arcothers who find theirideal village in Wilt-shire, and others whovow allegiance to someof the villages of theSouth Downs. Notso many plump for thevillages of the north,but I have a soft spotfor some of those oldvillages in the goodpart of Staffordshire,near to, the Derbyshireborder- Marchington,Needw ood, HoarCross, and Cubley. Alittle mor e austere,perhaps, than the

villages of the softer south, but, to aMidlander, full of beauty and charm. How-ever, I like to take my England as a whole, andfind " prettiest villages " wherever I ride. Itis the best way.

Wise WordspuNcH" has recently been inviting

leading industrialists to say somethingabout British industry, its part in the war, andits coming part in the reconstruction period.Sir Bernard Docker, the chairman of theB.S.A., said some true things about thecycle industry :

" . . where would our dispersed warindustries have been without the bicycle ?How would the A.R.P., police, postal andother public services have carried onwithout the bicycle ? When would war-time housewives have found enough timeto get through their work without thebicycle ? Even in the fighting line, anddespite the complexity of modern warequipment, the bicycle plays an essentialpart. No better method could be devised

. for the silent movement of airborne troopsin enemy territory than the folding para-chute bicycle . . ."

These are wise words, and a welcome tributeto the cycle industry. At last the ubiquityof the cycle seems to be receiving its duepraise !

" Beeropolis "T UST another name for Burton -on -Trent,J

the world-famous centre of the brewingtrade. I cycled through the streets of Burtonrecently and sniffed again the familiar heavyaroma of making, and rode carefully over therailway lines which cross some of the mainstreets. Mountains of barrels alongside the

By

H. W. ELEYsidings ; the chuff -chuff of little locomotivesdrawing trucks loaded with casks of thefamous Burton ale-destined for manyfar-off destinations. Quite a unique town,this Midland centre of brewing, and anancient one too, for I was reminded by anative that one may still see the ruins of amonastery there, along the banks of the wideTrent. Nearby there are quite delectablevillages-Newton Solney, Drakelowe andRolleston-on-Dove, where once the forbearsof Sir Oswald Mosley lived in a great mansion-now gone the way of most mansions and" vast estates."

Salute to a Schoolmaster'TALKING to a headmaster of a preparatory1 school the other day, I was delighted to

hear that once a week he lectured every childwho came to school on a cycle on the principlesof road safety and wise riding. Charts wereused, demonstrations given, and my friendreported a welcome freedom from roadaccidents. " Teach them young " is thegolden rule, and I am sure that more instruc-tion in schools about rules of the road wouldhave beneficial results. We have still far toomany accidents among children-and parentsdo not seem to do much to inculcate the rightideas.

In Better SupplyFROM observation, I fancy that the shortage

of bicycles has been very largelyremedied. In any case, an inspection of manycycle agents' windows recently indicates thatplenty of bikes are now on sale, and onenotes with satisfaction the pleasing varietyof models. The British cycle manufacturers,faced for long with intricate problems ofmaterials, and serious labour difficulties, havedone a grand job . . . and now they seem tobe turning their attention to that vital matterof export business, and one reads that theirplans are truly on the grand scale. Well, ifever a British product enjoyed a world-renowned fame, it is the British -made cycle. . and we may be sure that its reputationfor excellence will never be sullied.

" Teas Provided "IN the good old days, how welcome that

sign used to be to the cyclist who hadtravelled many miles, and who asked of lifenothing better than a pot of tea, and a bigplate of bread and butter. How well Iremember the wondrous meals which used tobe provided in little wayside cottages ; mealsserved with the affability and courtesy whichused to be characteristics of the Road. Allwho have ever belonged to cycling clubs willhope that when the days of rationing are over,and-presumably - fregh butter, and fresheggs will again be part of the normal teamenu-we shall again be able to dismount atthe picturesque cottage, go inside, - andenjoy high tea. Mar the day come soon !There is only one unpleasant memory I haveof " teas on the road "-and that is the placewhich styles itself " Ye Olde Tyme TeaShoppe." May we be preserved from this !

A Veteran Passes OnTHOUSANDS of " old timers " and a

host of folk in the printing and adver-tising worlds will have mourned the death ofA. J. Wilson . . . the one and only " FAED "-one of the early cycling journalists, a fineadvertising man, and a pioneer of the earlydays of the pneumatic tyre. For several yearsA.J. was in charge of Dunlop advertising, andthe agency he founded, and which handledsome of the best motor and cycle accounts,will long he remembered by the old school.


A corner of Chipping Campden.

Britain's Touring Grounds (6)A LTHO UG H small in area the Cotswolds are" deservedly popular as a touring ground, and maybe regarded as one of England's gems. I say small

'in area, and I would qualify that by adding that I amthinking of the Northern or Upper Cotswolds. PerhapsI am mistaken, but my impression, is that cyclistsgenerally do not tackle the northern and southern

sections in one trip, 'nor do they regard them togetheras one touring area. The Northern Cotswolds liebroadly in Gloucestershire, but parts are in Warwick,Oxford, and even a small part is in Worcester.' Thereis no other tract: of country exactly like the Cotswolds,with their multitude of thatched roofs, their yellowstone houses harmonising so gloriously with the richred -yellow of the soil, and the amazing collection ofcolourful gardens and beautiful cottages. There isa charm about the. region that - is almqst indefinable,because .no one would say that it is scenically superlative.

:Large tracts are just rolling hills 'and valleys with onlythe overall mellowness to recommend them. The hillsare alluring, but they are not grand. The lanes can beequalled, and even outshone, in the Chilterns and

;elsewhere, and it is by no means so well -wooded asmany other regions. That sounds almost like .adversecriticism, but it is not ; it is merely an attempt todiscover by elimination just where the charm lies.

Beautiful VillagesWE are finally driven to the conclusion that nowhere

else can one find so many lovely villages withina small area. None of the villages is unattractive,and most are beautiful in the extreme. Nowhereelse will the thatch, the stone, the earth and theflowers be found to blend so pleasingly and in such pro -

Notes of a HighwaymanBy Leonard Ellis

fusion. The world-famous villagescan be recited like a catalogueStanton, Stanwav, Ford, Ehrington,Snowsh ill. i Upper and LowerSlaughter, Upper and Lower Swell,Bibury; and so on. It is difficult to.single our any one as the best, as

1 opinions differ on such points': butthink that most will agree thatBibury is just sublime. Here wehave the green surroundedby typical 'cottages, the old churchcovered in wistaria_the clear -runningriver where yOu can watch the fatspeckled trout almost ready to eat

"from your fingers, but don't bemisled-they can't be caught. Hereyou pee arow of

cottage:so supedath ely beautifulthat they have been takenover by the Society of Arts.It is not only in small villagesthat the Cotswolds excel.There is 'a number of smallcountry [(orris that are ex-tremely interesting bothpictorially and historically.

'Of thee Ch inning Campdenand Burford can be single'dout as .two outstandingexamples of the perfect, un-spoiled, old-world countrytown.

An Old -world -TownYOU can walk round

Chipping - Campdenenthralled at every step by

'the successive vistas ofstone mullioned windows,overhanging eaves, quaintinns, dark little doorwaysoffering peeps of delightfulgardens, quaint- old shopswith " pop bottle " or" bull's eye " windows, and

, then to the old markethall, a picture in itself.Everyone will realise thesuggestion of bygone pros-perity or see the shadow of long -forgotten industry.In addition to these two towns, Northleach, Moreton -

in Stow-in-the-Wold and Winchcombe areall particularly attractive, and a paradise for thephotographer. Bourton-on-the-Water is called theVenice of England, because of the numerous little stonebridges spanning the stream that meanders through themain street. Bourton and Broadway are both verybeautiful, but' one notices with a tinge of regret thatthey have becOme so sophisticated that the real charmof the Cotswolds is almost missing. The SouthernCotswolds are probably finer from a scenic point of

. view, the hills:are loftier, and they may be more wooded.There is much -to see and enjoy, including Painsvvick.where 99 fine -dipped yews thrive in the churchyard.and all efforts to grow the hundredth are doomed tofailure, or so' the legend says. Then there is Ndllsworthand other attractive placeS, and there is also Stroud,which, although by no means unattractive, sims to

Ebrington, in the Cotswolds.

spoil the effectindustrialised.

My Point of ViewBy " Wayfarer -

The Toy of It AllCIRCUMSTANCES beyond my control kept me

away from cycling for exactly three monthsduring the winter which it is now almost safe to assertis past. This is a long period for one who, normally,cycles every day and whose week -end leisure is given_up to the best, the most enriching of all pastimes. Thejoy with which, about the middle of March, I resumedcycling can better be imagined than described. Myfirst business, of course, was to get back into form-a process which still proceeds at the time of writing.I recall that, on coming out of the Army in 1918, afterhardly seeing a bicycle for a year and a half, the sametask had to be faced, and that only a few weeks elapsedbefore I was able to do my century of miles in a day.But, alas and alack ! I am now 25 years older !

So I have been gently " playing myself in," withhalf -days of go's and full days of 6o's and with to milesa day between week -ends to help the muscles to functionproperly. But what interests me much more than thedistances achieved is the fact that once again I artaindulging in a joyous exercise : that once again, by myown efforts, I am making the road and the hedges slipby ; that once again I am conscious of " the wind onthe heath " ; that once again my wandering wheels aretaking me back to the happy scenes of old, and to thetiny houses where I have been wont to pause for meals.

Possibly some of the many gradients which are tobe found in the Midland shires have become (tempo-rarily) a bit steeper since my brief but all too longabsence ; possibly the winds (for the time being) haveblown more strongly, and with greater shrewdness,than was to be expected. Nevertheless, I have notconsumed much " acid," and I tun conscious of progressin getting back to form.

The joy of it all ! I have looked anew at the hillswhich ring my home town, beginning with Edge Hilland ending with the Wrekin. One day I saw withperfect clarity, about 5o miles away, the Black Mountainsstanding up behind the Malverns. I felt- that I hadcome into my own again, for these long-distance views,whether seen in the Midlands, or from the Chilterns,

or in Yorkshire, or elsewhere, are the particular parof our glorious and radiant heritage which makes sogreat, so compelling' an appeal to me, and whichcauses me to be more than satisfied to leave to other.people " the pictures," the theatre, and other artificialattractions of lesser degree.

Things LostIT is an easy step from this paint to two aspects of

the three months of non -cycling to which referencehas been made. For a portion of that period myactivities were restricted to eating and sleeping-bothpleasant occupations as hobbies, but not as a full-time jobfor a growing lad ! In my many waking moments I hadample opportunities for thought, and I was able toconjure up cycling pictures in abundance, dwelling onthe achievements of the past and looking forward tothe possibilities of the future. Thus the time passedquickly enough, and the loneliness of a private wardin hospital was dissipated by reason of the legacy ofmuch cycling in days gone by. For our great gamedoes fill the storehouse of the mind with a rich harvestof joyous memories -,a noble pageantry of things seenand things done.

When I " came back to life " and was able to resumebusiness, though still ranking as a non -cyclist, Idiscovered that the week -ends meant nothing to me.Normally it might almost -be said that I live for Saturday -and Sunday, but, so long as cycling was out of thequestion, well, Saturday and Sunday meant just asmuch (or as little) as 'Tuesday and Wednesday, orThursday and Friday. However (to quote one ofKipling's soldiers), " that's all shove be'ind me." Iam getting back to form as a cyclist, and week -endsare once again full of significance-in anticipation, inrealisation, and in retrospection. The things lost havebeen regained.

Delayed RepairsA Sii3ORT while before Easter I- looked in on a" cycle -man who carries out some of my veryfew repairs, and mends the occasional punctures I

by having become to some extent

bring home with me (he has just seen to a perforationwhich I have been carting about since last October !)and I found his workshop pretty full of bicyclesawaiting attention. In response to my " Busy ? " hesaid that the work was getting on top of 'him : hehad had to keep some of his customers waiting forthree weeks. " A lot of these jobs," he added, " couldhave been brought to me a couple of months ago, andI would have welcomed them during the winterslackness. But no, they are kept until Easter is withinsight, and then there's a gaudy rush." The hardschool of experience has its lesson for us all, if only wewill condescend to learn. A job well done in January isa better proposition than one not so well done-orperhaps not done at all-immediately before Easter -What " goes " for Easter applies also to Whitsuntideand the August Bank Holiday week -end. Moral : getthe job done early : avoid the eleventh hour.

The Price of SafetyTT is probably true to say that all the incidents and

accidents that happen to us, as cyclists, contain a awarning and a lesson. For example,. a few Sundays agothe attention of a friend of mine-a cyclist of consider-able experience and skill-was attracted by a low -flyingaeroplane, the -clamour of which drowned the noiseof a motor -car approaching from behind. Notunnaturally, my friend looked up at the aircraft notunnaturally, he made a slight swerve in the process.Just at that moment, the motor -car, going at a fast pace,overtook him and actually scraped the skin off thefourth knuckle of his right hand. This must have beenan extremely narrow escape for my friend. Possibly themotorist was seeing how near he could go to the cyclistwithout " downing ' him-a genial habit practised bysome motorists-but I cannot help thinking that mypal was entirely to blame for allowing his attention to-be distracted from the job in hand. As the old. taghas it, " the price of safety is eternal vigilance." Thus,the policy for every cyclist should be never to relax_his attention. Much can happen in a matter of seconds.So take care first, last, and all the time.

Will Others Please Copy ?SIR WILLIAM WOOD, a vice-president of the

L.M.S., wrote this a few weeks ago : " Therailways have never suggested that the roads belongingto the community, and paid for by it, should be deniedto the community. . . ." A refreshing statement whichmight well be borne in mind by others.

MODEL MAKERS,ENGINEERS, Etc.

We are urgently wanting PassengerHauling or Goods Hauling ModelLocomotives, from 3 gauge toI5in. gauge, coal fired jobs in goodcondition, also Track, Wagons,Crocodiles or Coaches for passengers,and anything else suitable. Large orsmall layouts. Give fullest particu-lars, photo if possible, and pricerequired., Also the smaller Electric,Steam and Clockwork Layouts. Afew of the above are for sale. Stampwith requirements.

BOTTERILLS MODELS,HIGH STREET, CANVEY, ESSEX

'Phone : Canvey 203.

FIVEPENCEwill bring you a copyof " Esperanto for AIL"a new booklet which tellsyou all about the inter-national language in usethroughout the world.Everyone interested in thedevelopment of inter-national friendship shouldobtain a copy. Send forone to -day to The BritishEsperanto Association, Inc.,Dept. P.M 20, Heronsgate,Rickmansworth, Herts.

" VIBRO-ARC " Engraving Pen

pFor rapid engraving any

metal -hard or soft.Operates from 4-6w.

Pod Battery or A.C. Trans -Free former.

HOLBOROW,(95), Boroughbridge, Yorks.

SHORTHANDDi ETON'S ONE -WEEK SHORT-HAND is used by over 60.000 menOM women. Accepted by Servicesand examining bodies. Test Lesson3d. Write Dept. P.M.. 92. GreatRussell St.. W.C.1.

IN ONE WEEKYou'll be glad you kept on savingwhen you can again buy an

ADANAAdana Printing MachinesTWICKENHAM, MIDDLESEX -

WAGON PARTSWood, Strapping and Plan 2 6 i"0"13

CRAY'S PRECISION CARDPARTS - -

N.E. 20 -TON HOPPER COALWAGON ... 1 - 1 6

L.M.S. CATTLE WAGON ... 1 9 2 3Lµ14.S. MILK VAN .. 1 D 23

Postage 3d. extra.BOOKS:ABC OF L.P.T.B.," 2:-. by post 225.

THE McINTOSH LOCOS. OF THE CALE-DONIAN ELT.," 3'6, by post 3 9.MODEL RAILWAY CONSTRUCTION,"1/6, by post 1'81.

"'MODERN LOCOS. 4: ELEC. TRACTIONOF S.R.," 1 6 postage 3d. extra.

" CARDBOARD ROLLING STOCK ANDHDW TO BUILD IT." 24, by post 24.

TYLDESEEY & HOLBROOK.Its Deammate, Manchester 3.

'Phone : Btu. 7312

WedsWanted!

They may meanmoney for you

e are open to consider anyideas or patents of practical

,worth with a view to makingand marketing them. Writein confidence to :

Edron Industrial Group,7 Park Lane. London, W.I

NO MAN CAN KNOW TOOMUCH OF HIS PRODUCT

BE fl hill 31 0 DE

Full particularson request. The Ultra Lens Company,

RICHARD BOCK,75, Finsbury Court, Finsbury Pavement,

London, E.C.2.

The Ultra Lens is a revealing eye of sixactual diametrical -36 area magni-fications, which brings out points ofstrength or weakness. Whether you

are engaged in manufacturing, buying orselling, it is an ally of real value. No

instrument you can buy will morequickly justify and pay for itself.

For the close scrutiny of every conceivableobject, metals, tools, fabrics, fibres, minerals,precious stones, paint, print, manuscripts,biological and botanical specimens, cuttingedges, fractured surfaces, raw materials,and innumerable other purposes, the ULTRALENS is invaluable, and presents in manyinstances hitherto unsuspected data whichcan be used to advantage.

The price is 14-54 complete in case with sparebulb, battery, and transparent measuring scale.

BOLT DOWN THAT MACHINE IN HALF THE TIME

with CINCH Bolt AnchorsSuitable for all fixings to walls, ceilingsand floors of cement, brick, stone, etc.

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manently. Will not slacken orwork loose. Sizes to suit all

needs. IMMEDIATE DELIVERY.

FreeSAMPLE AND DETAILS ON RECEIPT OF TRADE CARD

HOYT METAL CO. OF GT. BRITAIN, Dept.P.M., Deodar Rd., Patney, London, S. W.IS

FIVE gross of mixed B.A. screws,0 to 8, in brass and steel, round, cheese,countersunk heads, in, fin. and lin.long ; 8s. 6d. the lot. Three gross ofsnap -headed copper rivets, popular sizes,5s. 3d. the lot. Parcel of model maker'sbrass angles, 8ft. in Ift. lengths, 6s. 6d.tin. bore copper tube. 6d.per ft. 3/16 in.O/D brass tube, 6d. per ft. tin. borecopper tube, Is. 3d. per ft. kin. borebrass tube, Is. 2d. per ft. 3/16in. dia.polished steel rod, 4d. per ft. kin squaresteel rod, 5d. per ft. 18in. x l2in. x1/I6in. polished steel plate, 6s. each.

x tin. steel bars, 7d. per ft. Gauge 00brass coach wheels, 3s. 6d. per dozen.150 toy casting moulds, including soldiers,machine -gunners, cavalry, 12s. each.4in. Drummond lathe, all complete, inperfect sound condition, ektra changewheels, countershaft tools, £55 ; onlyused once. Steel moulds for castingmodel plane wheels, 25s. each. 2ft. x tin. xlin. copper bars, 4s. each. 21:in. borebrass tube, 3s. per ft. lain, bore brasstube, 2s. 3d. per ft. -W. Roberts(Engineer), Blaen Cwm, Penmachno, Nr.Bettws-y-Coed, N. Wales.CHEMICALS and Apparatus -many un-obtainable. -Price list from L. .1. Tuck,48a, Kenpas Highway. Coventry.

NEW Machinery. electric Motors, allsizes, Drilling MaChines, Pumps, Grinders,Welders, etc. -John P. M. Steel. Bingley,

FREE Electric Light this winter fromwind, build your own wind charger fromcar dynamo, easily built, reliable. Fullinstructions, drawings for building mast,head, propeller, 2, 81.-Pearse, Midta-phouse, Liskeard, Cornwall.

SECRETS of the Cinema." Newbooklet explains Projection, Sub -standardFilms, Sound, Technicolor, Trick Effects,Etc. Ideal for beginners. 1/6. Post paid.Library (9.5 mm.) and Accessories lists'3d.from P. F. U. Wellwood, Beaminster,Dorset.

12in. POWER BENCH BANDSAWS.Make your own. Send 10/6 for workingprints and photograph. Sound, simpledesign.-Rawlinson (PM), 34, CaegwynRoad, Whitchorch, Cardiff.

TOYS, MODELS and NOVELTIES.Send for range of popular designs withinstructions and hints on toy making.2/6 only, post free. -Harrod (P), 10,Beaconsfield. Road, Maidstone.

PROJECTORS, Films, Model Engines,etc., bought and sold.-Alderwick's CineSupplies, 33, Bridge Street, Haverfordwest,Pem.

ENLARGEMENTS, 81 x 6/. 61 x 4,brnited from 31 x 2k negatives, minia-tures, photograph. Stamp particulars.R. Hobbs. 83, Curling Crescent, Glasgow,S.4.

A.G. BATTERY CHARGERFor charging car accumulators, either 6or 12 volt at I amp., in enclosed metalcase, with change -over switch, inputand output flex, leads and pilot light.A thoroughly efficient ,ob. Price 601-,post paid.TRANSFORMER AND METALRECTIFIER only, with blueprint ofconnections. Requires wood baseonly. Price 361-, post paid. ..Parts,as above, for 2-voli radio cells, 1216,pest 8d.FOR TRICKLE CHARGING CARCELLS, parts with diagram. OutputIs amps. for 6v. cells, 301- set. For12v. cells, 351- set.

MICROPHONE BUTTONS, 213.

TELEPHONE WATCH RECEI-VERS, TI6 each.

ECONOMICELECTRIC CO.,/4, London Road, Twickenham,

Middlesex.Tel.: PCPesgreve 1319.

Whatever your age, you can nowstudy for the all-important Matric-ulation Examination at home on" NO PASS -NO FEE " term's."MATER "is the accepted pa0-port to all careers, and opens tipopportunities which would other-wise be completely closed to you.Ensure the success and security ofyou and yours through post-wardifficulties by writing for ourvaluable "Guide to Matriculation"immediately -FREE and withoutobligation. B.T.I. (Dept. 160),356, Oxford street, London, W.1.

RATCHET & REVOLUTIONCOUNTERS

Ask foeLeaflet No. I813'Speed up to6,000 r.p.m.

B. & F. CARTER&Co. Ltd., Bolton 5

ZiXtUarii.

Easily madeF r o ra Our

Castings.

&HALLAM& SON,

Upton, Poole,Dorset.

MINIATURE PETROL ENGINES forAeroplanes and Speed Boats.

Ins) oarier,d,",

Kits of Parts forsmall well tested, reliable

POWER DRIVEN FRET -DG -SAWwith complete instructions for assemb-ling. etc.. and three ways of obtainingMotor easily and cheaply.

Price 20/- each.Will cut out TOYS, FANCY GOODS,PATTERNS and 101 Saleable articlesin Leather, Wood, Plastics, etc.P. N. It ARHA " HllItoo."Wedmore Green, Coulsdon, Surrey.

SILVER PLATING SETSas supplied to Electroplaters, but inminiature, Pot` small parts, etc., in-structive small sets, 1.9!-, inc. post.Send 2d. stamp for printed folder.Materials for use with Electric Curriant,permanent Electroplating is carried out.Regret that no materials for Chromium,Nickel, Gold or Copper can be suppliedowing to permits being required.ARGENTA PRODUCTS (D. C)90. Harrogate Road, LONDON, E.9!

MYFORDLATHES -SALES and SERVICE

GARNERSSHEFFIELD ROAD, BARNSLEY

'Phone : 2866

iv

One of the following Courses taken at home in yourspare time ran definitely be the means of securingsubstantial promotion in your present calling, or entryinto a more congenial career with better prospects.

ENGINEERING, AERO, ETC.Radio-Aero Engines-Aero Navigation-AircraftDesign-WeIding-Aerodynamics--Electrical Engin-eering-Television-Electric Wiring-Talking PictureWork-Generation and Supply-Works Management-Metallurgy-Refrigeration-Planning, Estimating,Rate-fixing-Time and Motion Study-Aero Inspec-tion-Automobile Engineering-Sheet-metal Work-Engineering Draughtsmanship-Aero Draughtsman-ship-Jig and Tool Draughtsmanship-Press Tool andDie Draughtsmanship-Structural or RiF ConcreteDraughtsmanship - Sanitary Engineering - R.A.F.AND R.N. PILOTS AND OBSERVERS.

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Men and Youths urgently wanted for reservedoccupations as .Draughtsmen, Inspectors, etc.,in Aero, Jig and Tool, Press Tool, Electrical,Mechanical ancIother Branches ofEngineering.Practical "experieriCe is unnecessary for thosewho are willing to learn-our Guaranteed

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148, HOLBORN, LONDON, E.C.I

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