(12493) A. E. S. asks: 1. Can you inform your subscribers the degree of coefficient of expausion and the malleability of copper. brass, aluminium, soft iron, and steel? ) . ''he coefficients of linear expansion for the metals you name are per degree Fahrenheit, and at a temperature of 104 deg. V'ahrenheit, as follows : Copper, 0.00000610 ; brass, cast, 0.00001041; brass wire, 0.00001072; aluminium, 41.00001285; soft iron, 0.00000672; annealed steel, 0.00000607. No figures regarding malleability are reliable unless the condition of the sample is carefully determined. The general order of the pure metals in malleability, as given by Kent, is gOld, silver, aluminium, copper, tin, lead, zinc, p]atInur, iron. 2. What Is the metal or alloy Ita vlng the nearest coefficient to glass? A. Platinum is the only metal which has the same coefficient of expansion as glass. (12494) A. W. K. asks: Has anyone any experimental knowledge of a substance which, if shaped like a wedge, will weigh more when lying on its side than when lying on its back with the edge up? The writer frmly believes this to be possible, and that the heaviest substance is most likely to exhibit this phenomenon. A. We can answer your question that a wedge will weigh less when standing upon its head than when lying on Its face, since In the former position its “enter of gravity Is farther from the center of the earth than when It is on its face. It would r"quire most delicate balances to show this in any piece of metal which such balances can weigh correctly. (12495) F. R. S. says: I was interested in a method given in query 12456 for inscribing a hexagon in a circle, and hereby submit a geometrical solution for s a me . It is only a combination of two problems in the ordinary text books. I thought the solution might be o f interest to your readers. AllCa truelsc. C^. A. Theorem: Line 11 i j is side of inscribed pentagon. Proof: First, to prove that A C is a meun ratio between A R and R ( or A R :AC::AC: OR AW = A E' - E n' = (AF+ FE)' - E -i' = (AF + EB)'- /H' = AF'+2AFX EB = AF(AF + 2bB) A O(A F + FGl == AC (AC + AR) since A2R R E = —3- ( const ruetl-On) =a~C'+aOxab :. A R' - AC X AB= A 0' : . AB (AR - AO) = A C'' .·.ARXCB = AC or AB = ttt; ' . .AR: AO:: AO: OR AO CB MakeAS= CB :.SB = AO Now, from above : - AB: BS:: B8:A Sby construction and A D = A 0 by construction. :. A R : A D:: A D : A f, hence “ s BA D and S D A are .imilar, but “ 1 A D is isosceles.'. “ SDA is isosceles and A D = DS = 8B = A 0 .'. “ S D B is isosceles and < DBA = < A D S, but < D S A = < DBA + B D S = 2DBA. Hence <DSA = 2DRA:. Sum <sof “ ABD=5X < ABD = Srt. <s and > A BD = ! of 2rt. <s or “u of 4rt. <s .·. arc A D = i. of a circumference ur arc D A H is ! oj a cil'cumjcrcnce! Q. E. D. (1 2496) G. O. B. says: Y o ur answer to query No. 12467 in your June 10th issue interested me greatly. I want to ask: 1. If the rise in temperature of air during compression is due to the more frequent collisions of the molecules? A. The compression of a gas is the- effect of a mechanical force against the outward pressure due to the heat energy of the gas, which varies with its temperature. The result of the compression is to bring the molecules nearer together and produce more collisions per second by reducing the mean free path throug! which a molecule can move before it collides with another molecule. Tle outward pressure is increased, and the collisions are both morc numerous and more vio- lent. The tempemture is raised for both reasons. 2. What is the cause of the drop in temperature upon the air being released from pressure < A. The opposite aetiol, namely, expansion, produces the OPPOSitl effect, namely, a drop in temperature. The distances between molecules are increased, the mean free path is lengthenpd, and the number of collisions is reduced. (12497) O. W. E. asks: Would you kindly tell me where I could get some info 1Ilation regarding “colloidal solutions,” or a finely divided metal in a liquid? I am particularly interested in copper. If you have any SupIle1nts containing anything on this subject, kindly tell me what they are. A. You wiII find valuable articles upou colloidal solutions in the SullIement Nos. 1477, 1581, 1779, 1804, price ten ccnts each. The subject is treated in all the physical chemistries. We can send you Jones's “Physical Chemistry” fo] $4; also Zsigmondy's “Colloids and the Ultra-microscope,” price$3. (12498) J. S. R. asks: 1. I would like to know if there is auy SUbstance of any kind that smoke will dissolve or act on in any way. A. Smoke is a mixture, differing with the fuel which is burned, and with the incompleteness of the comhustion. The black POl tion whIch we usually call the smoke is simply the unconsumed carbon drifting away. This cannot dissolve anything. The gases from the combustion are able to act upon many materials and corrode them. There is also much hot-water vapor in smoke, which becomes water when it is cooled and aids the rusting of iron or corrosion of other metals upon which it may be condensed. 2. Is mercury a conductor of electricity, or anything in liquid forll that is? A. Mercury is a conductor of “'ectricity, as also are all Slutions of metallic salts, such as copper sulphate and common table salt, and most acids mixed with water. Th"rc arc thus a great many liquid c0nductors. (12499) H. O. S. says: Regarding the sounds given forth by the reproducer of a talking ma(hine, the manager of the record department of one of the pri.cipal companit's asserts that dul'ing a band selection all the instruments playing at one instant are given forth by the producer at one instant or at the same time. Now will you kindly answer this : Is it not a fact that any object giving forth different tones by vibration can have but one rate of vibration, with its accompanying tone, at any one instant or fraction of a second, it bf'ing irnpoR,ible for it to vibrate at two dif f(,l'PIt l'att'R at the samp inRtant O I have always understood and believed this to be so, and it seems to me to disprove the record department manager's assertion. Taking the length of the record groove paRsed over by the reproducer during one second, my opinion is that there is but one sound at any one time; but as there is one sound each smallest fraction of the “('('Dud, and tlwy follow each other so swiftly, tlH ear cannot compr('hend that it is lwing-dCcci ved, and beli(ves it hears more than one instrument at the same time. Could not this be positively ascertained by having two trombones or cornds play each a different sustained note, and see if the reproducer would give the two tones together? Or perhaps two differpnt notes on an organ would be more rneehanically exact and even. A. It Is not a fact that any object giving forth different tones by vibration can have but one rate of vibration with its accompanying tone at any one instaut 01 fraction of a second. It is very possible for it to vibrate at two different rates at the same time. The difference in tone quality of different voices and instruments is due to this very fact, and a vibrating string of piano or violin vibrates at a large number of rates at the same time. The record"r of a talking machine takes a form of motion dnl to. the resultant of all the forms of motion which it receives from the sounding instruments, and for this reason the record can impress upon the reproducer the same tones as it has received from the motion of the recorder. Doppler's Principle is the accepted explanation of this faot. Many tracings of combined tones have heen made. It is of course very difficult, if not Impossible, to extend such records to the very complicated resultants of the impressed curve of the disk of a talking machine for an orchestra, but the fact that thil is true of “impler compositions of tone leads with c(,l'tainty to the belief that it is also true of the complex tones of the' hand Or orch('stra. We do not look for any change in the accepted theory on the matt"r, 'rhe opinion of the manager of the record department which you quote is entirely in accord with our own. (12500) J. W. N. asks: Under the rules of science, as taught by the institutions of the world, is it possible for any man or 'gency to forecast the weather for montls Do yon know how to judge a motor oil? My booklet “Motor Lubrication” will help you. It tells of the perfect lubricating qualities of Panhard Oil For Motors- But it is mor f than an ordinary advertisement. I will send it free i£ you will give the name of your dealer. Don't merely ask for good oil-say “Panhard,” because: It is refined from the finest oil ill the wOl'ld-Pennsylvania crude. ALsolutely uniform in 1lll , l iLY, WII! uot carbonize if pr o perly O\ s l d. Just euough filtration-all free carLon removed. Not excessively filtered-perfect lllbl'ic:.ting body. Iubricates always at l,11 01” llorlai temperatures. Sold in .. Checkerbo,ud “ cans or in :; . 35 years of Oil lisuerieude ls been put into ,: Motor r.u)ricationf,-:nd this isfor )ou-if you write to.rlay. GEORGE A. HAWS Main Office, 74 Pine St., New York City /Ji:aler8: TFrite t( 1i s l 'fcial l'o-fJJ,naf-ve 1'lu·n Elbridge Aeronautic Motors Positively automatic in operation. Guaranteed to run ten hours at 1200 or more r. p. m. without adjustment or attention. The result of years of careful experiment under all conditions of flight. The lightest and most compact reliable mo tor ever buil t. American Amateur Aviation, a history of 1910 amateur achievements and our 1911 catalog for six cents. Elbridge Engine Co., 4 Culver Road, Roche.ter, N. Y. SWITTE ENGINES® Gas-Gasoline-Distillate Horsepower at one cent per hour avera)ej saves f () el, lepairs and time. Cheapest of all powers. (;IUH·aJltN·(1 1 i\'e.Years Speeia: pd,'e to illtl"odnee ill llew localities. \Y rite fo! eataiog stating size wuuted. WITTE IRON WORKS CO. 160S Oaklund Avenue, )(unsns City, lIissoul'l RunnIng Water If tbe Country Home Wllhout Fuel Cost m n lu mping engine costs you money for fuel every mmute it runs-a windmill ruus only when there is w i nd-both constantly require rq,airs-• but, the Niagara HydrauliC Ram cPutUIUOllSiy pUlllpS waLeI' :4 houl's a . . without cost of fuel, yearjifieryuanvlthhut necessity of repairs. “rite “at once for catalogue AA and guaranteed estimate. NIAGARA IlYDRAtLIC ENGlN n t0. 750 lleed Bldg., PbHa. Factory, Clie*tfr, I'm, JL RIFE RAM Water Raised to Any Height and in big quantities without pump-ma expense or bother with automatic Rtfc Rams, ] \.\ i¦ i ¦ water 30 feet for jrMcfa foot of foil -no treuhte or \ pumping expense. Satisfaction I uuaranteed. ******* ' | HI I RIFE ENGINE CE.t snna Trinlly Blag- N.Y, Learn Watchmaking We teach it lboroughly in as ld any mOllths as It formeriy took years. Does away wit 11 te(ious apprenticeship. 1loney earned while studymg. Positions secured. Easy terms. Send for ca taJog. lT. L.OUIS W A'I'UnMAKING 8UJIOOL.! L.St. Lou)., : se. NewYork Electrical School Offers a theoretical and practical course in applied electricity without limit as to time. Instruction, individual, day al(\ night school. Equipment complete and up-to-date. 8tudents learn by doi]ff:r 3 by practic:l applicttion are fittT3 to e;ter all fields of electr\cal r E gustry fu11; qualified. School open all year. Write for free prospectus. 27 West Seventeenth Street NEW YORK You Can Now Purchase A Complete Curti.. Power Plant With a Genuine Curtis.! Moior and Propeller. Curtiss power plants have been tried. tested and proven. When you buy one. it relieves you of all worry on this part of the equipment. In other words. it assures the success of your aeroplane. No experimenting or thought on your part is necessary-it has all been done for you by skilled experts. You receive the finished. perfected product. Model “ A” 4 cylinder, 25 H.P. Model “B” 8 “ 60 Propeller, radiator and equipment especially designed for each motor. le8cri m t''e Cil'cular “A" ft a tJi.e asking. THE CURTISS l[)'J'()K ( O. UlllllOlidspolt, N. Y. A erol a1 -otor by July 22, 1911 SCIENTIFIC AMERICAN 89 ahead, as is done by a few self-assert ; d prophets and so-called weather bureaus of this country? A. It is not possible to foretell the weather for any extended period, heyond the most gl'neral terms. The U. S. Weather Bureau after more than forty years of contiuuous practice do,s not att(mpt specific predictions for more thau thirty-six hours. Long-range forecasting is not yet reliable. The conditions which determine the motions of the vast m:sses of the atmosphere arc too little known. When a stonn appears in our western region, it is not Vossible to tell at what point it will !l'a ve the Atlantic coast, or what its path will Ie across the ciuntry. Tbe success of tle U. S. Weather Bureau in forecasting storms, frosts, and l'inl' foods is very l'email\able, and this work of the Bureau is worth many times its cost, hilt ttt'se men are very careful to disclaim tl” ability to predict the weather for any speciled place for any extended period. NEW BOOKS, ETC. TI Shipping World YeaR Book. A Desk Manual in Trade, Commerce, and NavIgation. Edited by Evan Rowland Jones. London: The Shipping World Offices, 1911. 8vo.; 175G Pi. The tw enty-fifth ed ition of this well-known annua l is bigger and bett er than evc'r before, Scarcely anything of value coming witnin its scope has ueen omitted. 'h( new tarls of Austria-Hungary, Bulgaria, Franc", Japan, Th” Netherlands, Sweden, and Greece are given. 'here is a complete port and harbor direc tory of tlie British Isles and a dil'lctory of all the commercial ports of tile world, with particulars as to accommodations, cbarges, tides, ti'ades, pilotage and towage, l'evispd up to the hour of vrinting . .mong new features of the (dition may ue mentioned the tables of fre(board, a digest of the merchant shipping .\cts from 18H. to 1\09, tahlt's of forl'ign moty, weights and measures, with English equ ival en t s, foreign tr ade statistics for 1 910, details o f t il wor l d 's shipbuilding outp ut for the pa st yp ar, and a m a:g of invalu able in tormation which the exhaustil'p index makes ('asily available. A I'W map of the world, esppcially prepared by J. G. Bartholomew, F. E. U. S., folds into a poc , et at the back of thp volume. This stlO\S tilt' l'ouhs of st<amers and railways throughout the world, ald the produets, ports, coaling stations and coal fields of all countries. ARgentina and Hel People of To-Day. By Nevin O. Winter. Boston: L. C. Page&Co., 1911. 8vo.; 421 pp.; illustrated. Price, $3. Argentina, like the other countries of South America, has received far less consideration than it is entit l ed to. One of the greatc'st food-producing conn tries of the globe, qlH-'tn or the Suuth American republics, first among thell all in import and export trade, with a capital ranking as one of the greatest citin of tlh world, Argent ! llu must quidH'll the lluIsf' of all who ar( atlractpd by the new, the progressive, the resourclful, and the ambitious. lYe have in the volume lefore us, to use the author's own designation, “an account of the customs, characteristics, amusements, history and advaneement of the Argentinians , and thl development a1 rfSOUICes of their country.” It is a brightly - w I'il lc'n and Well-made volume enriched by charming vipws and illus trations. KoRth Devon with West Somelset. By-Beatrice and Gordon Home. New York: Frederick Warne&Co. 12mo.; 220 pp.; illustrated. ''his is a little volume to fit the pocket, con taining some very good views of the countlyside, coast scenery, and pictlllesque buildings. The part of England with which it deals has an exceptional and distinctive beanty, as ev(ryonp knows. Such nantes as CovelJy, JIfl'ucombe, and Exmoor conjure up pictures of appealing quaintness, glimpses of rugged promontories and far-flung hays lying in purplish light, and stretches of wild mour and wild-blown spaces. We are now in the land of Lorna Doone and her “girt Jan nidd.” The book is not a ster('otyped guide, although its large-scale maps Rligllt nothing, but is almost like a gift-book in style and make - np-would, indeed, admirably serve that purpose-and is full of sympathetic de scription and discriminating illustration. Homestead. The Housflholds of a Mill Town. By Margaret 10 BYington. New York: Charities Publication Committee, 1910. 8vo.; 292 pp. Price,$1.50; postage, 20 cents. Homestead is a town. Homestead is also the mill which perpetnates the towu. But 2iargaret Byington's hook is mainly of the home life the mill town l('adR on the wages whieh the mil! pays. It is a comIunity at working men, repres(nting an parly 'euton· Celtic wave of immigration and a later Slavic lntlux. I'erhaps the main interest of the survey (' enters on “life at $1.65 a day.” We arf not so much drawn to a stUdy of middle-class living and humdrum resppctability. Ouq literature must give us either the prince or | the pauper—either Brewster's millions or the I w.dow's nute. “ese nme-dol lars-a-we ek m(n I wrth wives and familips can allow themselves · IJllt twenty-two (,pnts ]pr man for a day's food.! The Committee on Trade and Commerce estl-I mat",l that in Pittsburgl.l a liberal provlslOn of food for a fam.ly of five could not be PUl -chased for less than$11.88 per week. From th('s!' contrasting fgures we may draw our own conclusions as to the uuenviable state of the unskilled work(r in the steel mills. Rents are high. The twelve-hour day, continu('d in many cases through the seven days of the we('I, leaves no time for anything else save food, a pipeful of consolation, and sleep. This is of course the shadow of the picture, tlH'l'e are ligher lights. The yolure is one of the six which comprise the notable Pittsburgli Survey findings, and Is remarkable for tIll way in which it goes to the very heart of things and tabuiatps human strivings, ]ongingH , and lim.tatiollK in column: of cold type. TIle Chemistly of tIle Coal Tal Dyes. By Irving W. Fay, Ph.D. New York: D. Van Nostrand Company, 1911. 467 pp. Price, $4 net. 'ie hook gives a good presentation in con dsc form of the prilcipal classes of organiC dy('stuls. An idpa of its contents and their all'angPIllt'nt 1WlY I obtainrd frolu the chaptp1 hpadings, \vhicll 31'p as follows: 1. Intro duction ; 2, Coal Tar and Its Products ; ; and 4. The Hydrocarbons and their DerivativeS. G. The Nitro and Nitroso Dyl's. 6. 'rhe 'Iri-l)llenyllllC'thanp Dyes. 7. rhe Classileution of the Coal-Tar Dyes. 8. The Azo Dyes. 9. The Seven Food Colors. (Devoted to the seven dyes whose use in foods and beverages has ueen sanctioned hy the U. S. Uovernment). 10. The Pyronines. 11. 'be IndaIines, IndoplH-noIs, Thiazinp8, Oxazines. 12. The EUllIodines and Safraninps. 13. 'he Quinoxaline, Quino-line, and Acridine Dyes. 14. Aniline Black. Hi. The Alizarine Dyestuffs. 16. Indigo. 17. The Sulphur Dyes. 18. Mordants. 19. Experimental Work. In point of publisher's technique the book deserves the highest praise, and there is a wealth of fully written out structural formulae. Th e tn'utm ent of the subject leaves nothing to be desired. A nU lllb"r of new prints an an occasional loughncss in literary style should be ditn'ina tpd by tension in a later pdition. A cUiiols omission ot'L'urs in the index, which, und"l” the entry “Indigo,” fails to give the most important l'efel'l'nee, nalnely, that to the chapter on Indigo on page 37G. The last portion of the book, pages 417 to 458, forms a laboratory guide for the prepara tion of sor” of the typical dyestuffs . Dictionary of English and Spanish Technical and Commelcial Terms. By William Jackson. New York: Spon&Chamberlain, 1911. 12mo.; 164 pp. Price,$1. An excellent idea is embodied I this neat little glossary, for it concerns itself with listing and intprpl'pting tllP Rpccial terms of the Iron, stepI, hardware, aul engineering trades for the benefit of those who are pngaged In ordering or in filing orders for thes” products lltween English - speaking and Spanish-speaking cOlin tries. As it is ilposilJle to find many such t(>('hnical na les in the ordinary dietionul'Y, this eompilation should promote ease of comlJll'reial intel'course and find favor with a large class of buyers and shippers here and abruad. Between three and four thousand words and phrases are alphabetically listpd. How to Make a Wm!less Set. By Arthur Moore. Chicago: Popu ar Mechanics Company, 1911. 12mo.; 84 pp.; illustrated. Price, 25 cents. Boys all over the country are dabbling in “wireless,” and lllany more will take up the hohIJy whpn tlll'Y find how l'asily a short distancp outtit may he constnted. rrle instructions here givpn are for the making of a set that will transmit to a distance of four or five miles. How to Live in the Countly. By E. P. Powell. New York: Outing Publishing Company, 1911. 8vo.; 300 pp.; illustrated. Price, $1.75 net. Mr. Powell is well known as a prolific and sympathetic writer on rmal subjects. le speaks from the fulness of an appreciative personal experien('e, and in this instance tells how a large life may be lived on a small acreage. Both the dweller in the country and the city lllan wh o dream s o f f arm life lllay gai n str pngth and b readth of o u tlook from tl aut hor's prac t ical wisdom a n d inSpllllg description. The work is primarily a guide to choosing and ma , ing the most of a country hOllie. The chapt"r entitled “Can we maku it pay?” touches upon what is to most of u the vital point, and warns while it encourages . The Book of Roses. By Louis Durand. New York: John Lane Company, 1911. 8vo.; 101 pp. Price,$1 net; postage, 8 cents. The rose is everybody's favorite, symbolical of all the beauty and fvagrance of life. Almost any soil can be made to grow roses of one kind or another. The various soils and their preparation forms the theme of the first two chapters. The question of planting is argued. and budding, sowing, and striking as methods of propagation are examined with thoroughness. Much space is given to describing the YarietiEs-wiId, autulll blooming, decorativC, and climbing roses. 'he full-page plates will delight the heart of the flower lover, for they s(em almost to exhale the perfume or the specimens they picture. The ambition of every tiremaker in the world is to some day make a non-skid tire as good, and as popular as the famous NOBBY TREAD Eighteen months ago, Nobby Treads were first placed on the market. Since then they have been sweeping the country, replacing every form of non-skid tire or non skid device on cars in every state iu the Union, and in every possible kind of service. Skidding Protection - These Lig, thick. diagonally pliced knobs grip the slippenest road or pavement at every possible angle. They hold th,e wheel against skidding, and drive slipping” even on a wet asphalt pavement. They reach down deep into muddy or saudy roads. and hold the whfd secure where a plain tread \ouJd spill around unhindered. Wearing Quality-In decided contrast to the ordinary, so-called. non-skid tires, those tough rubber knobs expose so large a surface to the wear and lear of the road that it takes thousands of miles of the hanlest kind of serVice to wear them smooth. When they finally do wear dOWII, a plain tread still remains good for many more miles of service. For sa(ety's sake-foT economy7s sake equip your car with “ Nobbies “ WHAT do you want Ktobuy f We can tell you where to buy anything you want f Write us for the addresses of manufacturers in ANY line of business Machinery, 9 f Novelties, Special Tools, Equipments •I New Patent Labor Saving Devices MUNN&COMPANY, Inc. PUBLIS HERS OF THE SCIENTIFIC AMERICAN 361 BROADWAY, NEW YORK, U. S. A. Own a Good Saw A poor one is not “good enough” for anybody. You want a saw that cuts quick and true and holds its sharp teeth edges-a «t Simonds SaW (Pronounced Si-mondJ) It's made of tough, hard Simonds Steel, rolled and tempered by us especially so the teeth will hold their sharp, quick-cutting points against hard usage. -\ Nearly 80 years' experience is behind every \ Simonds Saw and our guaranty. \ Write for “The Carpenter's Guide Book"- j, \ FREE-and learn how to care for a saw. SIMONDS MFG. CO., Fitchburg, Ma •• Chicago Portland, Ore. San Francisco ^^f4M&£^2 New Orleans New York Seattle %:'/?;".$%£'•' ift?»~><^S«»* 90 SCIENTIFIC AMERICAN July 22, 1911 Wood-Working machinery For ripping, cross· cutting, mitering, grooving, boring scroll-sawing, edge moulding, mortising; for working wood in any f."Dner. Send for l'atalog'lle A. SENECA FALLS MFG. CO. 695 Water Street Seneca Falls, N. Y, U. S. A. THE SEBASTIAN 1S-INCH ENGINE LATHE HIGH GRADE LOW PRICE Auto m obile Bu ilde rs. Ga rages. Re pair an d G eneraI Jo b bing Shop s fnd this the ideal lathe for their w ork. Cata log free. The S ebas tian Lat he Co . 120 C ul vert SI .. Cin Cinna ti. Ohio Friction Disk FOR LIGHT WORK. 1118 TheMe Great Advanta-e8: The speed can be instantly changed from 0 to 1600 wltbout stopping or shiftIng belts. Power appilad can be graduated to drive, with equal safety, the smallest or Jalgfst drills within its range-a wonderful economy in time and great saving tn drill breal.age. t Send for Drill Catalogue. W. F.&Jno. Barnes Company Drill 1»»” Ruby Street, Established 1872. Koekford, III. Make$20 to $40 Dav 111aaL selling the Automatic rCI ffCCK Combination Tool in your home county. AFenceBuilder'sTool, Post Puller, Lifting Jack, Vice, Wrench, etc. Used by Farmers Teamsters, in Factories, Mills, Mines, etc Weight 24 lbs. Capacity 3 tons. No experience necessary. Free instruction. Write forspecial offer to liveagents. Send no money. Name County where you live. Automatic Jack Co., Box 46* Bloomfleld, Ind. ELECTRIC D:!m!S SPECIAL Grinders MACHINES Polishers ROTH ELECTRIC MOTORS 198 Loomis Street, Chicago, IIIs. ?§uUS£«RINDST0NE8P If so we can supply you. An sizes mounted and ulmounted, always k(!pt in stock. Remember, w*> mnke a specialtyuf select ir;t> st ones for all ape . cial pUrp(Se8. ;ewt for catalogue “ 0 “ The CI,EVELAN 0 STONE O . 6th Floor, Hickox Bldg., Cleveland, 0. Complete lists of manufa<rers in all lines supplied at short notice at moderate rates. Small and special lists compiled to ordec at various prices. Estimates should be obtained in advance MUNN&COMPANY. Incorporated, PUBLISHERS List Department Box 773 New York City MASONS NEW PAT. WHIP HOISTS save expense and liability i ncid ent to 1levators. Adopted by principal storehou ses in New York& Bo s t o n Manfd. by VOLNEY W. MASON&CO., Inc. Pro,'ldenee. 1,. I.. U. 8. A. Experimental&Model Work Circular and Advice Free Wm. Gardam&Son, 80·86 Park Place, N. Y. INVENTORS Let us build your model before you apply for a patent. Advice free. G. SCHWARZ&CO., 123 Liberty St., N. Y. THE SCHWERDTLE STAMP CO. »SEEl STAMPS LETTERS&FIGURES. BRIDGEPORT CONN. Modh&Experimental Work INVENTIONS DEVELOPED SPECIAL MACHINERY . , . E.V. BAILLARD CO., 24 Frankfort St.,N.Y. mw ANTED rpUi :s s I experience in maktOg Dies. Tools and SpeCIal Machtnery, Exnert work. Complete eqUlpment. NATIONAL STAMPING&ELECTRIC WQRKS aw <n r, limrnn Street. - - ChIC8fO, Ill. IliBRlCATESVc UNO 118.1Y2J4 n orNib6 (lntoD St ' C. B fS LVa co fL'Ift” £USA ll.f|]l||jnn Corliss Engines, Brewers and Bottlers' Machinery l A . VILter MFG. CO. 899 Clinton Street, Milwaukee. Wi•• !Hf A Comparison of the German and American Navies (Oontinued from page 78.) 9%, and ours from 9 to 12 inches-all Krupp armor. The upper sides of all these !Ships are protected by plates averaging 7 inches in thickness. But the American !hips mount main batteries of modern 12-inch guns, against the greatly inferior 11-inch weapon in the Teutons. The eight “Connecticuts” have each a broadside of four 12-inch 45-caliber rifles, which, as we have said, will send a shell through any plates the Germans carry, while the latter's 11-inch 40-caliber weapons are useless against more than 6-inch armor at 8,000 yards! And every one of the five “Georgias” and three “Maines” mounts four 40-caliber 12's which are effective at 8,000 yards against plates 8% inches thick. The remaining ten “Wittelsbachs” and the older Americans are probably of too little offensi"e value to be seriously considered ex ? ept for a second line of offense -certam I t IS, however, that the olld 9.4's o f t h e '' Witt e I sb achs “ wou ld b e ab so I uteIy useless at ranges where the 13's of the “ Ala bamas, ,, “Kearsarges” and “ Indl.-anas” could work fearful havoc with their 1,100-pound shells. The superior speed of the German vessels might indeed enable them to close in upon the Yankees, so as to sgive their guns a chance, but they would be fearfu].]y punished before they could hope to even mat- UNITED STA STATES __ SERMANY AT 8.000 yaRos F KRUPPARM RUBBERExpert Manufa cturers Xv vJ£jfJl_4.Ev Fine Jobbning Work PARKER, STEARNS & CO., 288-290 Sheffield Ave., Brooklyn, N. Y. CRUDE ASBESTOS DIRECT_FROM MtNES R. H. MARTIN, (FICE. ST. PAUL BUILDING 220 S'way, New York, PREPARED ASBESTOS FIBRE for Manufacturers use This diagram shows that the batteries of United States ships have far greater penetrative power than those of the German ships. ters up in that way. We have hitherto taken no account of the secondary batteries; because so greats is the skill to which gun-pointers have attained in recent years that it is doubtful if battleships would fight at ranges at which the lighter guns would be greatly destructive. It is true that they could even at a distance inflict much harm on the unarmored portions of the hull (fore and aft) and upper works, but almost all the complement of a modern battleship are stationed behind armor; and furthermore, the high trajectory of the 8's, 7's and 6's makes it more difficult to hit with them than with the larger pieces. Armored Cruisers. When it comes to armored cruisers the navies are more evenly matched. ThB splendid “Von del Tann” finds no counterpart on our list, more's the pity; and even the “Bluecher” has some advantages over our “Montanas"-as in the matter of speed, for example. But the rest of the Germans are a sorry lot, and our own “West Virginias” are not much better. As for the three “Charlestons"-they are hardly worth mentioning, being utterly useless from an offensive point of view. In the matter of torpedo-boat destroyers, the Germans are much better off than we are. They have ninety-six of these ready for sea, ranging from the ,latest models of 620 tons and 34 knots speed to old and slow (25-knot) craft ')f 400 tons. We possess sixteen 400-tonners of 25 knots !Speed and twenty brand-new boats of 700 to 750 tons and upward of 31 knots speed. On the other hand, the American navy has some twenty-six submarines to the GeIan navy's eight; but this kind of craft is more especially adapted to the work of coast defense, and therefore need not be taken into considBration to any great extent. In fast protected cruisers and gunboats the German navy has a considerable superiority over our own; but however useful the former may be as scouts for the fleet they cannot have any actual value in battle. Theref?re we have left them out of our consideratIOn of the relative strength of the two navies. A summary of broadsides (for modern strategy pOI'nts to the universal adoption of broadside firing in actions between feets) of the various groups of ba ttleships' as in the accompanying table, will show at a glance the immense superiority of the American ships in the ability to deal telling blows. Herewith is given in graphic form a diagram showing the oveTwhelming superiority of the American battle fleet in the matter of heavy guns; 68, or exactly half of the total, being 12-inch rifles capable of successfully attacking at 8,000 yards the heaviest armor worn by the Germans. On the other hand, not a single one of the Kaiser's ships could at that distance pierce the main belt of any of the Americans, and only 32 of the newest rifles (ll-inch, 45-caliber) would be effective against the Yankee topsides. In time of stress it is .the armored ships that count, arid the tables given above demonstrate beyond peradventure of a doubt the present offensive superiority of the United States fBet. Germany is contemplating equipping her newest dreadnoughts with ordnance of 12.2-inch caliber, but these undoubtedly powerful weapons will be more than compensated for by the new 14-inch rifles which are to be mounted in our “Texas” class. recently laid down. All this, however, is beside the question, as our object has been to demonstrate that at the middle of the year 1911, the German navy, far from being a menace. is not by any means the equal, offensively, of the fleet that flies the Stars and Stripes. Heart Diagnosis by Electricity (Continued from page 81.) the main circuit. This gIves the various “derivations” or “leads": (1) Right arm and left arm, (2) right arm and left foot, (3) left arm and lrft foot. The wire from the left fQot always goes into the same main wire and the left electrode occupies· the same position in the circuit as the right arm does, otherwise an inverted electrocardiogram will be obtained. It is neoessary to attend to these details, because' s('m e diseased conditions cause an Inverted electrocardiogram. From tho switehes the two main wires lead to the galvanometer. In· most instances when the patient is connected to the galvanometer, there is a large permanent difference of potential between the two parts of the ' body (so-called body-current) where the electrodes are attached. This deflects the fiber far to one side, aud must be compensated. A commutator is placed in the circuit which serves the purpose of connecting in and sending in either direction around the main circuit a current from a battery (reduced to suffcient strength by a resistance coil). This is sent in the OPPOSite direction to the “bOdy-current,” and serves to neutralize the primary body potential, and to effect what is called “compensation of the zero-current." For making phonocardiograms simultaneously with electrocardiograms, the microphone is wired to a smaller galvanometer. The wiring of the microphone is simple. It is conneeted with a dry battery in a circuit with the primary of an induction coil. Wires from the secondary lead to the junction points of the wires from the galvanometer and resistance coil. The constant battery current passing through the primary induces no current in the secondary: Changes, however, in the strength of this primary current, as the result of sound vibrations on the Valuable Books The Scientific American Cyclopedia of Formulas Edited by ALBERT A. HOPKINS. Octavo, 1077 pages. 15,000 Receipts. Cloth.$5.00; half morocco. $6.50. ( This valuable work is a careful compilation of about 15,000 selected formulas, covering nearly every branch of the usefuI arts and i I.dustries. Never before has such a large collecbon o / valuablef ormulas, useful to everyone, been offered to the publif. Those engaged in any b ranch of industr y wi ll p iobab ly find In this vo lume m uch tha t is of p ractIcaI u s m thetr respeb. ye callings. Those in search of salable articles wJlch can be manu factured on a small scale. will find hundreds of most exceDent suggestions. It should have a place in every laboratory, factory and home. Handy Man's Workshop and L a b ora t ory Compiled and edited by A. RUSSELL BOND. 12mo .. 467 pa.es, 370 illustrations. Price,$2.00. ( This is a comp:Ition of hu m dred. of valuable .ugg estions and ingeniouS ldcas for t. e mechanic ar.d those mechamcallY lncl. ned, and tells how all kinds of jobs can be done with home-mace tools and appliances. The suggestions are practical. ard the sol utions to wh ic h th ey re f er a re oof f req u ent o occ ur ren ce. I t m lY be regar de d as th e best collection of id eas of r eso urc efu l: men pub lished, a nd a p p e als to all ll those who fn d use for too s .• ittier in the home or workshop. The book ls fu!IY l llustrated. m many cases with working drawing.. which show dearly how the work is done. Concrete Pottery and Garden Furniture By RALPH C. DAVISON. 16mo., 196 pg. 140 illustrations. Price, $1.50. ( This book describes in detail in a most practical manner the various methoc of casting concrete for ornamental and usef e l purposes. It te lls h ow to make al l kinds of c oncrete vases, ornamental flow er p ots^ concrete pedestals, co n crete benches* concrete fe nc es. e tc. F ull practical lttruc h. on s are aleven- for constructing and finishing the different kinds of molds. maki e- the wire forms or frames, selecting and mixing the ingredien!s. covering the wire frames, modeling the cement mCrtar lr.to form. and casting and finishing the various objects. Wlth the lOfona-'_:JD given in this book, any handy man or novice can make many useful and ornamental objects ID cement for the adorn ment of the home or^ garden. The information on coo work alone is worth many times the COlt of the book. The Design and Construction of Induction Coils By A. FREDERICK COLLINS. Octavo, 295 page. 159 illustration.. Price,$3.00. « This work g iv e s in minute details full lractical direclio:s lor making eight different sizes of COlIs. varylOg fr?m a small one giving a one . half-inch spark to a large one SWIng twelve-lDch sparks. The d imensions of each and every par t down to the smalles t screw are given, and the dlrecbons are w ritten in language easily comprehended. ^ Much of the matter In this bo o k has never before been published as, for iDstance, the Icuum drying and impregnating processes, the !akm g .f adjustab. mica condensers, the constru m tion of interlo cking reversing switches, the set of complete wiring dl agrams, etc The dlustrations have all been made from origmal drawmas, which were made especially for this work. Industrial Alcohol Its Manufacture and Uses By JOHN K. BRACHVOGEL. M.E. Octavo. 528 page', 107 illustrations. Price, $4.00. <]I This is a practical treatise, based on Dr. Max Maercker's Introduction to Distillation “ as revised by Drs. Delbruck and Lange. It comprises laW materials j malting, mashing nod yeast preparation, fermentation, disti llation, rectification and purfcation of alcohol, alcoholometry, the value and slgmficance O a tax-free alcohol. methods of denaturing. its utilization far light, heat and power Jro l uction. a statistical review and the United States law. ThI IS one of the moot author! tabve bok issued o n the s ubject and is ba sed u pon th e re ear ch ei and writin gs of thh e most eminent of Ge r man y 's spe ciali sts in the sciences of ff erme ntati on and di stm ation . It cov ers the ma nufacture of alcohol from the raw material t o the final rectified and purified product. including chapters on denaturing, domestic and commercial utilization. fny 0 / these books will be sent, postpaid, on receipt 0 / adverlised price MUNN&CO., Inc., 'Publishers 36 I Broadway New York City m Maf ApPr!!us: PJL^*^S Grand Book Cataloeue. Over 700 enicravines 25c, Parlor Trick. Ca t alogue . free . M ARTINK A&C O .. Mfr• . ,4H3 S ixtb Ave .. New York Your PATENTS aDd BUSINESS In ARIZONA Incorporate Laws the mos t liberal. Expense tbe least. Hold meetiu2s. transact busineu anywicre. Blanks. B y ·Law. and forms for makin r stock full-paid for cash. property or services. free. President Stoddard. FORMER SECRETARY OF ARIZONA. re.iel aeen! for many tbouland companiel. Reference: Any bi Ariroafc STODDARD INCORPORATING COMPANY, 80xOOO PHE. ARIZONA July 22, J911 SCIENTIFIC AMERICAN 91 microphone, set up induced currents in the secondary, and these are recorded by the galvanometer. In healthy people the electrocardiogram assumes, in the majority of instances, a certain typical form. The term “typical” or “schematic” is used instead of “normal,” since slight deviations from it may occur in people with normal hearts. When any muscle is excited to contract, the active portion is always electrically negative to the part at rest. This is true, therefore, in the heart, and electrical changes show the course of excitation. The curve for each heart period presents throughout three principal waves upward, indicating an electrical negativity of the base of the heart with regard to the apex at three different instants in a single cardiac cycle. These three elevations have been designated by Einthoven as P, R. and T. The curve presents, also, in many instances, two slight excursions or waves downward, depressions, indicating a negativity of the apex of the heart with regard to the base at two different instants in each cardiac cycle. These two depressions, though less constantly present than the three elevations, have 'been designated by Einthoven as Q and B' By the course and height of these waves, as shown in the records, the physic ian can tell by eye whether the heart undergoes normal electrical changes or abnormal; in 'e latter instance an analysis of the abnormal 31ppearances of the record throws light upon the disease of the heart-muscle which is present. The two accompanying illustrations will give a clearer conception of the method of observation. The upper of the two diagrams is an electrocardiogram. The lower is a diagram, on an enlarged scale, of a section of the electrocardiogram, which will make plainer the changes in a Single cardiac cycle. Waves with the· apex upward indicate that the base of the heart or the right ventric:e is negative to the apex or left ventricle, and is therefore excited at that time. Waves with the apex downward have an oppOSite significance. Wave P is due to the excitation of the atrium (or auricle). Waves Q, R, S and T occur during the excitation of the various portions of the ventricle. What this instrumental investigation signifies not only for the discovery of disease, but also for diagnosing its preClse cracter, It IS as yet too early adequately to judge, but many physiologists and pllysicians believe that it will prove to be a very valuable aid to the medical profession. While the galvanometer, the phatographic recorder and the auxiliary instruments have in this country already furnished data of importance in connection with animals as well as human beings^ the work in Europe has been far more extensive, as a larger number of stations have been established. Light-producing Bacteria and Fireflies AFEW years ago Prof. Molisch determined that of all the light-producing bacteria Pseudomonas lucitera produced the brighest light. F. Alexander MeDer-mott presented before the Biological Society of Washington the results of his own further experiments with this organism. A culture of these bacteria was sent to Washington by Prof. Molisch, so that the form used was identical with the original material. Mr. McDermott finds that the bacteria will grow in gelatin or a liquid medium, doing better however in gelatin; in all cases it needs the presence of from 2.5 to 3 per cent of common salt, or certain other mineral. A culture will continue to give off light actively for about a week, reaching the maximum 48 hours after inoculation. The light is a soft green af “considerable intensity.” The following formula furnished the best culture medium: Peptone, 1 per cent, Asparagin, 1 per cent, Magnesium chloride 0.5 pel cent, Sodium chloride 2.5 per cent, Glycerine 0.5 per cent. Solutions of greater cancentration were not so favorable to the growth of the baderia, and Mr. McDermott suggests that the organism is “apparently sensitive to overfeeding.” It is perhaps simply an indication, however, of the osmatic limits of the minute cell. The spectrum of the light emitted runs from yellow-orange to indigo and is less J constant than the light from certain firetlies, though similar in appEarance to the naked eye. Although the light from cultures in a liquid medium looked whiter to the eye, the spectrum was the same. The luminous tissue of fireflies had already been shown capable of again emitting light when moistened, after having been dried in a hydrogen vacuum-even after the lapse of from thirteen to eighteen months. It had also been found that the light was brighter when the tissue was moistened with hydrogen peroxide solution. Similar results are now reported for dried cultures of Pseudomonas. Oxygen under pressure also restored the luminosity. The general character of the light produced by the firefly and by these bacteria is the same. but there is no reason to suppose that the process by which it is produced is the same in the two cases. But it is probable that the luminosity is connected with oxidation in both organisms. Th e C urrent S UppI ement THE opening article o the current SCpplement, No. 1855, deals with the Grand Trunk Transcontinental Canadian Railway.-Major George O. Squier's paper on Multiplex Telephony and Telegraphy is continued.-The heat-insulating efficiency of vacuum-jacketed bottles is dis-•cussed by A. A. SOerviIIe.-Commandant Renard's paper on “What Constitutes Superiority in Airships” is concluded.-Before the Society of German Marine Engineers, the contributions of Goethe to science and industry are considered.-Jacques Boyer writes on the application of the Duss>ud principle of illumination to moving picture projection.-The Berlin correspondent of the Scm"tiYic America” describes an apparatus for recording loss in weight.-The possibilit l es of aeroplanes in naval warfare are discussed by a German naval officer.-Illustrated descriptions of automobile novelties are presented.-Ralph C. Davison writes on the enormous discharge of dynamite rendered necessary in the construction of the new cut-off of the Delaware, Lacka'Wanna and Western Railroad near Andaver, New Jersey-A gaod article on taxicalogy is contributed by Professor Levin' of the University of Berlin. The Secret of the Maple IT is probable that every observant person who has visited a maple-grove in the early spring, while snow-banks are yet lingering in sheltered hollows, and has seen pailful after pailful of sweet sap drawn from the auger-holes in the trunks, has wondered what forces govern the flow or the sap. When the warm sun touches the tree-tops the flow increases. A rise of a few degrees in temperature often causes a great increase of flow, if the rise passes the zerO point, on the Centigrade scale, that is, the freezing-point of water. But a considerable change of temperature in which the fluctuations dO not cross the zero line causes no marked change in the fow of the sap. In the consideration of these and other related facts, the conelusion has been reached that neither expansion of gas in the wood, nor expansion of water, nor expansion of the waod itself, is the underlying cause of the pressure which produces the flow, but that this pressure arises from the effects of temperature in altering the osmotic permeability of the pith-ray cells. A New Route Across Africa.-The German Government is rapidly progressing with the railroad that is to connect Daressalam with Tabom in German East Africa. A force of 10,000 laborers is at work on the new road, of which 374 miles have been constructed. According to the Deutsch Ostafrikanische Zeitunf the uIHmate extension of this road to Ujiji, on Lake Tanganyika, is practically assured. As the Belgians have now decided to extend their upper Congo railway system to the west shore of Tanganyika, the time is not far distant when H will be possible to travel by rail, lake and river acrass Africa from Daressalam to the mouth of the Congo. It's a pleasure to fix things up about the house -if the tools are sharp. Ask your dealer for Carb.rundum sharping stones. The m.st remarkable sharpening agent ever discovered. H your dealer hasn't them send direct. No. 107-F Round combinati.n st.ne for carpenters . .$1.00 No. 108-F Oblong combination stone . . - . - . 1.25 No. 108-F Oblong combination st.ne in aluminum box . 2.75 No. 191-F Scythe and grass h.ok stone ...... .25 No. 1l4-F Sportsman's pocket stone in soft leather case . .75 No. 149-F Pocket stone in cardboard case..... .15 THE CARBORUNDUM CO. Niagara Falls, N. Y. HOW TO BUILD A 5 H.P_ GAS ENGINE AT HOME In Scientific American Supplements, 1641 and 1642, E. F. Lake describes simply and thoroughly how a five horse power gas engine can be built at home. Complete working drawings are published, with exact dimensions of each part. « Price by mail for the two Supplements, Twenty Cents. .. .. .. .. « Order from your newsdealer or from MUNN & CO., Inc., PUBLISHERS, 361 BROADWAY, NEW YORK dampproof - stainproof -finishes FOr CONCRETE ATTRACTIVE AND BRICK Trus-Con Exterior Wall Finish, applied with a brush, makes walls better than new-has a beautit,tl. uniform flat tone-is always clean because readily washed-has a dampproof. weather-resisting surface-hard as fint-becomes an inseparable part of the concrete, sealing the pores and filling the bair cracks-does not peel or crack off like paints. Trus-Con Exterior Wall Finish is a scientific preparation. especially compoundeJ for finishing and protecting concrete and masonry. Furnished in a variety of many pleasing colors. Write For Free Trus-Con Color Card. Tell us about your requirements. so we can gire detailed suggestions and name of nearest dealer. TRUSSED CONCRETE STEEL COMPANY, 402 Trussed Concrete Bldg .• Detroit, Mich. No-Rim-Cut Tires 10% Oversize Six Months' Sales, 220,000 The G.odyear No-Rim-Cut tire, as most motorists know, has changed the whole tire situation. The demand has become overwhelming. It is six t i mes as large as two years ago. These tires cannot rim-cut. The 650,000 in use have proven that. They are 10 per cent oversize. That means IO per cent Iore air - more carrying capacity. With the a ve rag e GOooR No-Rim-Cut Tires With or Without Non-Skid Treads THE GOODYEAR TIRE&RUBBER Branches and Agencies in 103 Principal Cities Canadian Factory: Bowmanville, Ontario car it means 25 per cent more mileage. Thousands have found that these two features together - No-Ri1l-Cut and oversize-cut tire bills in two. Yet these patented tires now cost no more than standard clincher tires. They fit any standard rim. Our Tire Book -based on I2 years of tire making - is filled with facts you should know . Ask us to mail it to you. COMPANY, First Street, AKRON, OHIO (B51) We Make All Sorta of Rubber Tire. Main Canadian Office: Toronto, Ontario 92 SCIENTIFIC AMERICAN July 22, 1911 Switch 'ower o Ideal 'crete Blocks, built by the Lake Shore ( Michigan Southern R. R. La Porte, Ind. Tycrete Blocks are the 20th Century Building Material This switch tower is the type adopted by the Lake Shore System and they have built 16 of these switch towers at various points along their line. More are constantly being erected. Tycrete blocks are particularly adapted for the construction of switch towers, store houses, depots, culverts or bridges. The IDEAL line of concrete machinery is the standard adopted and used by several railway systems. Write for our catalog and further information. It will pay you to investigate. Ideal Concrete Machinery Co. London, Ontario, Canada 510 S. Emerick St., So. Bend, Ind CONSERVATION The AUGUST Magazine Number of the SCIENTIFIC AMERICAN Issue of AUGUST 12th, 1911 The next magazine number of the Scientific American, August 12th, 1911, will contain a series of articles by leading authorities, which will deal with this vital subject of the conservation of our natural resources. Ex-Chief Forester the Hon. Gifford Pinchot, whose earnest fght for the preservation of the coal lands of Alaska has led to a favorable decision of the Land Office, which greatly strengthened the cause of conservation, will open the number with an article on the Conservation of our Forests. The Director and Chief Engineer of the Reclamation Service, F. H. Newell, will write a general article on the past work and future plans of the Reclamation Service. The Director of the Bureau of Mines, Dr. Joseph A. Holmes, will show that the waste of our supplies of coal is due not merely to careless and extravagant management in the mining of the coal, but also and very largely to methods in burning the fuel. Dr. David T. Day, of the United States Geological Survey, will prove, in an article on the conservation of oil and gas, that, as with coal, so with oil and gas, it is possible to effect large economies by judicious management in the oil and natural gas fields and by the use of improved appliances in burning these fuels either for light or power purposes. Dr. Hugh M. Smith, Deputy Commissioner of Fisheries, will contribute an article on the Conservation of Fish, Oysters, etc., and Seals. Conservation is a word to which we are liable to give too restricted an application. In addition to the above articles, the August 12th number will contain the usual Editorial, Aviation, and other Departments. Electricity U!loading Bananas by ElectricitY'- Fruit steamers I” New Orleans and MobIle are now bemg unloaded by means of electric conveyors. The conveyors are •provided with vertical legs that enter the hatches of the vessel. These legs support travelmg cha .ns four feet apart, which are connected by cross brs carrying canvas po()kets. Bunches of bananas are placed in these pockets and hauled out of the vessel. The loading of the conveyor is perrormed from three decks, each deck filling every third bag. Each conveyor has 1 capacity of twenty-five hundred bunches of bananas per hour. Avoiding Pole Lines in a Welsh Town. -In order to avoid the use of poles in the streets of a town in Wales, it was decided to run the wires on brackets supported on the sides of the buildings and the roofs. The brackets are made of angle i iron and extend about six feet from their support. At first there was some hesitation On the part of Owners about giving the right 'Of way over and along their buildings, but this was overcome by proper precautions on the part of the .company. The system has proved very successful, and it avoids crowding and disfiguring the streets with poles. Outdoor Ironing.—One of the most dreaded days of the household in summer time, is ironing day. Even though elec-l tric flat irons are used, the heat may become almost unbearable owing to the fact that the 'W'Ork is invariably done indoors. 'rhe ,Commonwealth Edison Company of Chicago does nDt see why the ironing should not be done outdoors 'On the porch, or in some other convenient location. All that is needed is a sufficiently long conductor to conect the flat iron with a lamp socket in the house. This idea has been seized upon to provide a very attractive circular showing the advantages of Outdoor ironing and incidentally advertising1 the use of electricity for this branch of the house work. Electric Fans f'r the Sick. -According to pDpular impression public service corporations are organized robbers. It is almost impOssible to combat this prevailing idea. Recently, however, the Electric ¦Supply Company 'Of DeKalb, Ill., has demonstrated that it can perform a work of charity in which there is no personal gain whatsDever, except for creating a better feeling on the part of thB public toward it. The company has notified all the physicians in the city that it will furnish electric fans and power to operate them without ()harge, to aJI patients who are unable to pay for such service and who, on the suggestion of the physician would be materially benBfted by the use of fans. This applies not only to such houses as are wired, iut to others as well, the company offering to install the necessary circuits, gratis. New Lighting Apparatus.-A very eCDnomical method of producing light by means Of small incandescent lamps was shown by M. Dussaud before the Frencl Academy of Sciences. He mounts 16 small lamps with one-inch 'bulbs around the edge Of a revolving disk, provided with a set of contacts so arranged that when the disk rDtates each lamp receives ¦current for a fraction 'Of a second. It is well known that tungsten lamps have the property of lighting up very quickly when the current is applied. He uses a 10-volt lamp and it receives 20 volts, or much more than tle normal current, but for a very short time. Much more light is thus given fDr the same amount of current. Each lamp in turn passes when lighted before a fixed lens so as to project the rays, and as the lamps pass rapidly the light seems continuous. His main object is to provide .a suitable light for lantern projections, and he claims to secure a light equal to an arc lamp for a very small current such as a moderate-sized primary battery will give. Thus it can be used where there are no current mains at hand. It is well adapted to be used as a small searchlight upon fishing boats or to be carried by soldiers, and for army use the battery can be placed in a sack upon the shoulders, together with an optical signaling outfit. Such' an outfit can be used also I upon aeroplanes. Science Death of G. Johnstone Stoney.-Dr. G. Johnstone Stoney died recently at thd age of 85. He had been astronomical assistant to the late Earl of Rosse in 1848, professor of natural philosophy in Queens University, Ireland, in 1852. and secretary of Queens University from 1857 until its dissolution in 1882. He was known chiefly for his writings on astronomy. An Opera Glass Comet.-We have received a communication from Prof. Edward C. Pickering 'f Harvard College Observat'Ory, in which he states that a comet has been discovered by Kiess on July 6th in R. A. 4 h. 51 m. 51.8 s., Dec. 35 deg. 15 m. 2 s. The comet can be seen •w1th an 'Opera. glass, and at the time of its discovery was moving southwest and had a visible tail. Col'r Photography.-A patent, 992,151, has been issued t'O Rodolphe Berthon of Lyon, France, for a color photography apparatus which c'Omprises an objective with a diaphragm therein having a trichrDmatic screen, a sensitive surface and means interposed between the sensitive surface and the objective so that the images on the screen are separated by refraction at points in close proximity and projected in a microscopic state on the sensitive surface. The “Internati'nal Week” of Upper Air Observati'ns.-A circular from the headquarters of the International Commission On Scientific Aeronautics announces that, 'Owing to the fact that the attention of British as well as manv foreign meteorologists will be taken up with the meeting of the British Association during the early part of September, the dates set for the “international week” of aerological observation throughout the world, in 1911, have been changed ¦from September 5-9 to September 11-16 .. A Meteor'logical Outpost in the South Atlantic.-An important addition to the meteorological reseau of the southern hemisphere was made early this year in the establishment of a meteorological station of the first order in Fernando de N'Oronha, a little group of islands about 194 miles northeast of Cape St. Roque, 'On the Brazilian coast. The islands are used by Brazil as a penal colony, and contain upward 'Of two thousand inhabitants. Darwin has described a visit here in the “Beagle,” and the “Challenger” alsD touched here. The statioIi is under the charge of two German employees 'Of the Brazilian telegraph service, and sends daily telegraphic “eports to Rio de JaneirD. The Flight of Seeds.-1t is popularly believed that winged seeds from trees travel to great distances on the wind, but the investigations of a British sci entist, who has spent much time at Singapore, indicate that winged seeds have a far narrOwer range of flight than have “powder” seeds and plumed seeds. The greatest distance traveled by the winged seeds of a, fDrest tree Ofbserved by this authority was 100 yards. Under the most favorahle circumstances, he calculates, it would take this plant just one hundred years to spread three hundred yards, and 1,500,000 years to sprHad from the Malay Peninsula to the Philippines, if a land connection existed. Illuminati'n with Ne'n Tubes.-lI. Cli. Ed. Guillaume recently lectured before the Astronomical Society of France on the subject of neon light. Neon, one of the rare gases of the atmosphere, is now obtained on a comllercial scale in the process of making liquid air. In a vacuum tube it has several excellent qualities as an illuminant. Owing to its extraordinarily feeble dielectric cohesion the voltage required is relatively small. M. Guillaume exhibited a tube six meters long, which was illuminated with a current of 1,000 vol<s. A light of 1,320 candle-power was produced, with an expenditure off only 850 watts, or 0.64 watt per candle-power. The light, which is of a warm golden yellDw, is described as being peculiarly pleasing. The lecturer also described a 'process 'Of re1Oving from the tube traces of Other gases, especially nitrogen, the presence of which seriously diminishes the illuminating power of the neon.