' .. INVENTIONS DISCOVERIES RADIO AUTOMOBILES AVIATION HOME WORKSHOP R EM IN(, TON !:1(.1-1 U"(LER JANUARYHow to make the new and thrilling winged toboggan.Page7225CENTS nventions I Hope toakeEdison I A 'i . I . Nomatterwhat set you buy,be surethedealer .. putsmgmmne Radiotrons: UV-199$2.50 UX-199$2.50 UX-120$2.50 UV-201-A$2.50 UX-201-A$2.50 UV-200$2. 50 UX-200$2.50 WD-11$2.50 WD- 12$2.50 WX-12$2.50 UX-112$6.50 UX-210$9.00 Rearons: UX-213$.7.00 UX-216-B$7.50 A " UX"or" !JVX " 111beis the same as thfcormponding '"UV"or" WD" iube, excptinthe designof thebase. Radiotron UV-201-A, stan dardvacuumtubefor storagebattery sets. I ) ' . or every ristmas .. 10 .useon(y genuine RCARadiotrons UEADalltheclaimsofalltb.emakersofradio ft.sets-and thenremember thiswhenyoubuy-that getting whatisclaimedforasetdependsupon thequalityofthevacuumtttbeputinto- it.Y oil cannot getdearness-you cannot get distance-you getvolume-unless the tttbes get it.That is whyitissoimportanttolookatthebaseof every tube,to besureitisa genuineRCARadiotron. great gift foraniJfall- atS2?0 Aradiofanwillappreciatea"spare"Radiocron, justasanautoist asparetire.Burd1e Radiotrori-a genuineRCARadiotron- costsonly $2.50.Ifyountewhatmakeof secamanowns, anydealercantellyouwhichtype of Radiotronhe uses,andyoucangivehimexactlywhathewould choose forhimself. for ownersof Super-HeterodlJnes thenewtube EveryownerofaRadiolaSuper-Heterodynecan bringhissetrightup-to-darewiththelatestim-, provemenr,ifyougivehimthenewdrybattery powerRadiorronUX-120,andtheadapter.The adaptercostsbut$1.50.Andthisnewtubemeans greatvolumewithbettertonethanever! RADIOCORPORATIONOFAMERICA CHICAGONEW YORKSAN FRANCISCO .. MADEBYTHEMAK E R SOFRADTOLAS Copynghted matenal .... _, __ January, 1926POPULARSCIENCEMONTHLY e4 ow olster Model 6-C is a six tube,antenna set,loudspeak_trenclosed,ample $pace for rectifie-r and all ba:uries. Parade of Stations One station after another parades by as you turn the Kolster regulator. Whateverisontheaircomesiri easily, perfecdy. : evea s ' ''L Subtle overtones now developed.Awon-drous achievement in . tonal perfection Reproduction such as you've never heard be(ore. Theclimaxin reception,theidealin reproduction.. Yourearwill instantlydetectKolster superiority.. You'11 a rangeof notes,allthedelicate shadingsandindi viduality. If Zimbalistplays,it isZimbalist-as if you were actually in the studio.There: isnointerference,nomuffling,noexag geranons or represstons. If thePresidentmakesaspeech,if McCormacksings,ifLope4 if Godowsky plays the piano--whoever or whatever is broadcast is reproduced faithfully. AKolster neither adds to nor subtracts from broadcasting. Sonowcomesnewreality.Allthe rich tonal coloring in its natural beauty-not meresoundbut vivid;lifetike. And all with simplicity.Just turn from one station to another.The Kolster has a singlecontrol.No .. tuning;with numerousdials.Nochartofstfl\nge numbers. Free frominterference.No howls.No }:>ackgroundnoises.Nooverlapping; of stations. '.. Inshort,theradioyouve: :exp_ected. Therefinementsyou'vewanted.Radio at its best. To hear a Kolster gives a new thrill.It sets new standards. Hear the Kolster in your own home or at aKolsterdealer'sshop.Five beautiful De luxe, but not expensive. FEDERALTELEGRAPHCoMP.ANt (of California) Woolworth Building,New YorkCity 1 Thla aeal on aradio or tool advertisernent "aignifiea the approval of the INSTITUTEOFSTANDARDS.See page 6,(opynghtL'd 2 0 uar c1ence 'fheMagazineof InventionandDiscovery JANUARY,1926;Yo!.108,No.1 25a ntsaCopy;$2.50aYear Publishedin NewYorkCitya: 250FourthAvenue Features in This Issue outdoorsisthestudioof RemingtonSchuyler,thenoted AmericanI ndianpainter ;butno-where, wethink you willagree, hasheportrayedthetingling thrillofwintermoremaster-fullythaninthepaintingon thecoverofthisissue.I f this picturemakes you want t o buildawinged tobogganand try it on thenearest hill,your enthusiasmwillbedoubled whenyoureadthegraphic descriptionofthisfascinating new wintersportbyitsorig-inator.Turnto page 72. *** WHETHER clothesmake themanbrnot,itis fairly certain that spotted and shabbyclothesnevergeta manveryfar.Foreveryonewho valuesthemeasureofself-respect to be drawn fromaneatappearance, t heart iclebyanexpertdrycleaner onpage23holdsawealthofusefu I informationonali ttleunderstood subject. Thea utogiro,amazingflyingmachine. t hatfl apsita wingslikeabird, described onpage13ofthis issue A FTER allthat hasbeensaidand .\..writtenabout-memoryandhow toimproveit,aColumbiaUni-versityprofessoratlasthasrca 11 y hit the nail on t heheadonpage26of thisissue.He offersusno short cut to perfectmemory.I nstead he shows .. ushow we canmanagemore efficiently themarvelousfiling systemofourmindsandso increaseitsworkingcapacity. ProfessorRobertS.Wood-worth also citesinteresting in-stancesofmenwhohavenat-urallyremarkablememories. *** HAVE youbeencaughtby thehardcoalshor tage? T here's asure way to beat the problem,asyouwilllearn whenyouturntothearticle onpage 34. I ttells you just how you can burnsoftcoalin yourfurnace almost,ifnotquite,asef-fectivelyasanthracite. *** THAT often - dreamed- of achieverrient-v e r t ica l flightfrom t heroofsofbuildingsand homes-may be brought a stepnearer realitybytheremarkableflying machine,theautogiro,picturedhere. Onpage13youwillreadofitsre-markabletestflight. And 200Other Articlesand Pictures,including-Pace Popular ScienceInstitute o Standards. . .. ..6 WhyCuriosityPays .. . .. . .. .. . . .. . . ... . ..q By Thomas L.Masson T heInvisibleLifeline o( the $c.II ByPeterVischer FlapsIts WingslikeaBird............. .13 By A rthurA. Strtart Inventions Edison StillHopest o)la ke. . . . .. .14 By JohnR.Mdfoho11LessnnsinMa&ic ... .. ... ,,,............. . .16 ByHoudi11i TgTbjs theFace o fFutureMan? By ErnestBrttmecke,Jr. SouthA1nericanSnakeEnrmItftI0I!!$ f0 8} Francis Gow-Smi ell CuriositiesjnSnor t . . .. . .. . . ... . . . . . ... .. . . What aCleanerHnsIcttrnccl 19 20 22 23 ByWatso11G.Clark The1926Ecl ipse. ...... . ..................25 ByNt11ulo11Burke IsYourMemoryJ3adlyManager!? . ,. . . . . . .. .26 ByRobertS.Woodwortlr .PI!. D. WhenTrainsCrash.. ., . .. . . . .. . .. .. . . .28 By Trtunall Stete11 s Prize-Winnersinthe Contet. ....... . Where Ol dHo usesGo,:::. ... , , .. WhenBurnjng SoftCo'\\ ... ......... . Tracking theKiller byis ......... . 3 1 3.1 MechanicalFarmHandMilksCo\vs Page 38 Boards andBoxes from\Vaste ... ... .. . BOV!iBuildSCenicRllilw;ur ... .. . . , . ,, ...... . AmericanHome ShippedtoFrance ......... . AutoCarries Wire. Cutter ...... . ..... . ..... . 38 39 39 40 I a king a5awmlll Into theI"orest . .. . . .. . .. . .40 Know Your Car.................40 Powder Puff CanBeChanged EailY, ,. ,, , ,,41 "Vacuum Cleaner"Unloads Cargoes .. , . .. . ..41 OdditiesonWheels. , ., , ,.. ,. ..42 ueer Boats and Their Skiers . . . .. . .. .. .. .43 F jye:PoundMotion- Pictur eOutfit,I0 It Reflectors Teachhaw toDralv Stlesl'nI ndustrialGasMasks. .. . . ..... . ScienceIs Pu ttinewcas tose . ....... . Have YonSeenT hem AnYBigger?. ., .. .. .. CampFire Girl MadeofButter . . ... ... .. . . LihthouseIsaRadioSet. . ... ... . .. . ..... . Wher eRnotsAreDugorPipes .,,, ...... , .. CcleCar fro mAirlaneParta ............. . FoucBottles anE .......... . Trc.veling DollseachFirstid ......... .. . . RadioSt>iMade into aBook , , , , ,.. , .. , .... . NewestM acvels o fAyiatjon.... He FriesEggs onIcc .................. ..... . . 49 50 so 5 1 Sl 51 52 54 POPULARSCIENCEMONTHLY ... '' HomeWorkshop .. . . .. . . . ...71 Better Shop Methods . . .. . . . . 76 And OtherTimelyArticlesand Pictures l&luedmonthly.Singlecopy,25 cents.'venrly subscription to United States, Itsp088e9illoos,and Canada, 12.50: lorelgn countries,S3.Entered!as second-class matt.er Dec.28 .1918.at the Poet 011\ceat New York under the net orMarch 3. 1879; a.ddltlollAlentrY asaeoond-classmatteratDunellen, N. J ,Entered as aecond-clas8 matter at t he omce Department, Canade..Printed In u. s. A. Cop)Tight1925. bY\be Science Publlshlng Co.,Inc.Thecontentsof tblll lllll!!BZinemust not oo reprlnt.edwithout perml.sslon.InpreeenttngIntis editoriAlcolumnanumerousstories or newproducts of applledscience.P OPOLAR Scu:NCMONTHLYdoes not underwrite the businessmethodsofthetndlvlduallll or con0Cl'll8 pi'Oeluclng t hem.The WJe of POPULAR Sci:ENC MO!lTKLTarticles,or quotatlonafromt hem ror ato