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The Bachelet Magnetic Wave HealingSystem.

Lesson on Electro -Plating.

How To Make It Department.

Crystal Detectors and Electro -ThermalAction.

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"THE EXPERI1vTENTER'S MAGAZINEAmericanRadioHistory.Com

H. GERNSBACK, Editor H. WINFIELD SECOR, Associate Editor

7r1 x

ri CAVOL. II NOVEMBER, 1914 NUMBER 7

High Voltage Discharges Thru Vacuum TubesSome of the Wonderful and Spectacular Éffects Obtained

THE discharge of high voltage, moreparticularly that delivered by an in-duction coil of the "Bull Dog" typeand giving one inch or more spark,

thru vacuum tubes, gives very beautiful

Fig. 1.

and wonderful results, as will be evidentfrom the illustrations herewith. First,

Fig. 5.

we see how such a discharge looks whenpassed thru the flame of a candle at Fig.

1. Beautiful striae or stratification takesplace, the current seemingly not findingan evenly conducting path thru the can-dle flame. The striae seen are believedto be due to a shifting of the gaseousatoms or ions about the path of the dis-charge or an action takes place similarto electrolysis.

An elementary form of Plucker's Va-cuum Tube for observing the striae cre-ated by a high voltage induction coil cur-rent passed thru it, is observed at Fig. 2.This tube has its central portion greatlyconstricted and the smaller the bore ofthis part between the end electrodes, the

Fig. 6.

more pronounced the striae effects.Plucker has used such a tube with thebore thru its major or central position.so small that it resembled a capillarybore.

When a powerful magnet has its mag-netic field of flux concentrated on thestriae in such vacuum tubes, (includingall Geissler tubes), the effect created isboth very wonderful and instructive. AtFig. 3 is illustrated the effect known asPlucker's plane, when the flux of themagnet is concentrated on the negativeelectrode of the vacuum tube. Stratifica-tion is often produced in this mannerwhen none was observable previously.

How the magnetic flux effects the streamof electrified ions at the negative elec-trode of a ball shape tube is shown at

Fig. 2.

Fig. 3.

Fig. 4, which phenomenon takes thename of "Plucker's curve" after its dis-coverer. How this curve forms itselfwhen placed over both poles of a power-ful magnet is depicted at Fig. 5; thenegative electrode phenomenon being

` 1

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here picturedillustration.

Fig. 4.

also, as in the previous

"The Electrical Experimenter" is published on the 15th of each month at 233 Fulton Street, New York. There are 12 numbers per year. The subscription price is 50 cents a

year in U. S. and possessions, as well as Canada. Foreign countries 75 cents a year. U. 8. coin as well as U. B. stamps accepted (no foreign coin or stamps). Single copies 5 cents

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All communications and contributions to this Journal must be addressed to: Editor, "The Electrical Experimenter," 233 Fulton Street, New York. We cannot return unaccepted

contributions unless full return postage has been included. ALL accepted contributions are paid for on publication. A special rate is paid for novel experiments; good photographs accom-panying them are highly desirable.

Title registered U. S. Patent Office. Copyright 1914 by E. I. Co., New York.

AmericanRadioHistory.Com

Nov. 1914 THE ELECTRICAL EXPERIMENTER 99

The form of the electromagnet usedfor this work is seen at Fig. 6, as alsothe insulated cradle support for the va-cuum tube. Beautiful effects are obtain-

IDIBi11tII1011lulLu1I1IiuI!1lirul'J.'ulll

Fig. 7

able when Geissler or Vacuum tubes arerotated. A device for driving a "Star"of three tubes by hand, is illustrated atFig. 7. A vast number of substancesnot sensibly phosphorescent when ex-hibited to any light rays, are made sowhen subjected to a high voltage electric

Fig. 8discharge in a vacuum. Mr, Crookes, ofvacuum tube fame, found the diamondto be one of the most sensitive and re-liable substances for this experiment.

Our illustration at Fig. 8 shows thephosphorescent diamond, caused by plac-ing it in a vacuum thru which a high

Fig. 9potential electric current is passed. Inall these experiments much depends ofcourse upon the degree of vacuum in thebulb or tube; entirely different effects

THE BACHELET MAGNETIC WAVE HEALING SYSTEM.Bachelet, of Aerial Railway fame, has

also given us a new and efficient meansof treating certain human ills, so it isclaimed, and a number of careful testsmade by duly qualified medical men hasproven that the "Bachelet MagneticWaves," as they are termed really do

A Patient being treated by

perform and effect efficient results.Moreover these results are obtainedwithout the usual Tesla or Oudin highvoltage and high frequency apparata,which is somewhat dangerous to useand also there is sometimes a bad nerv-ous shock given the patient when theseman -created lightning flashes are ad-ministered. All this fear of electricshocks, et cetera, is done away with inthis apparata, which is used as shownin our illustration.

The patient or that part of his anatomyunder special treatment is placed be-tween the two magnetic wave coils ofthe Bachelet machine. In accordancewith the well-known rules of magnetism,and especially when alternative currentis passed thru the coils, an alternating,sinusoidal, and rhythmical magneticfield of flux is produced or set up be-tween the coils and also in any bodiesplaced in the space separating the coils.These alternating flux lines are sug-gested by the arrows path in our illus-tration, and of course, depending uponthe frequency of the A. C. supplyingthe coil, this magnetic field reverses itspolarity many times a second, and afrequency of 60 to 120 cycles, etc., canbe employed. The magnetic flux linesthus created set up or induce alternatingcurrents in the bodies placed betweenthe two exciting coils and these inducedcurrents produce heat and other cura-tive results thereby, as positively provenby research in the matter due to severalprominent physicians.

Where direct current only is availablea special switchboard and rotary con-verter is supplied with the apparatus asalternating current, or at least a pulsa-ting current, must be utilized.

In the words of the inventors andperfectors of this apparatus:-

"Bachelet" Magnetic Waves.

When in operation a sphere of magneticlines of force is created between thegenerators. An inconceivable numberof minute magnetic particles, each withits negative and positive pole, are throwninto space by each generator, exchangingpolarity with each other within thissphere and penetrating all substances ofa non-conductive nature and setting uppowerful currents of low voltage andhigh amperage in all electrical conduc-tors, thereby exciting molecular andcellular activity in the tissues of thehuman body, magnetizing at the sametime the iron, oxygen, and other positiveelements in the blood and tissues.

Normally the magnetic field of theearth's atmosphere accomplishes thisresult.

This magnetization constitutes what istermed "The Electric Potential" of thehuman body, and without this magnetiz-ing influence it is more than probablethat life could not exist upon our planet.

When the electric potential of thehuman organism is at its normal heightthe body possesses the necessary vitalforce to ward off and combat disease.When this vital force becomes diminishedthe body loses its power of resistanceto the attacks of disease and graduallythe latter wins the upper hand.

It has been proven by numerous teststhat the Bachelet Magnetic Wave Gene-rators DO raise the electric potentialof the human body as much as 33 percent.

being observed with low and high va-cuum respectively. A number of com-mon minerals are mounted up in fancyGeissler tubes obtainable on the market,as diamonds are too expensive for thispurpose. The phosphorescense of ru-bies, (which can be a number of small

inexpensive or reconstructed ones), isseen in Fig. 9. The effect is very beauti-ful and no matter how deep or pale the"natural" hue of the stones, the phos-phorescense effect is a bright, rich red;utterly beyond description or imitationin black and white.


100 THE ELECTRICAL EXPERIMENTER Nov. 1911

Experimental Electricity CourseBy S. Gernsback and H. Winfield Secor

LESSON 15.ELECTROPLATING.

PART I.Electroplating is the term applied to

that art involving the use of the electriccurrent in the electro -deposition of metalsor their salts on other metals, or metall-

WAX MOULD

E.I.Co.NY.Fig. 1

ically coated substances. Common formsof electroplating, well known to everyone now, are the familiar nickel plate onvarious fittings, utensils, instruments;gold plating and silver plating, as em-ployed in the finer arts, including jew-elry, etc., etc.

Fig. 3-B. Foot Power Drive.

Besides these more well known phasesof electro -deposition of metals is thatbranch formerly termed galvanoplastic,

Fig. 2. A Useful Copper Plating Outfit

which has now been abandoned for theterm electrotyping, or the electrotypeprocess. The several industrial branches

of electro -chemistry, including electricalrefining and analyzing, electroplatingand electrotyping are now embraced un-der the general nom de plume of electro -metallurgy.

Electrotyping was originally evolvedby De La Rue, in 1836, who observedthat in a Daniell's cell, the copper de-posited from the solution upon the cop-per plate electrode serving as a pole,took the exact impress of the plate, in-cluding all scratches, indentations, etc.,upon it.

During the year 1839, Jacobi in St.Petersburg, Spencer in Liverpool, andJordon in London, independently devel-oped out of this discovery, a method ofobtaining by the electrolysis of copper,impressions in reversed relief, of coins,ornaments and stereotype plates, etc.Murray, another investigator, made theimprovement of using molds of plasteror wax, coated with a film of plumbagoin order to provide a conducting surfaceupon which the deposit could be made.

The making of copper electrotypes isreadily affected by suspending a suitablemold in a cell containing a saturatedsolution of sulphate of copper. Thruthe cell a battery current is passed, themold being connected to the cathode ornegative terminal. A copper plate im-mersed in the solution of the cell, actsas an anode, or positive terminal. Thecopper anode is gradually dissolved intothe solution at a rate equal to the rate

Fig. 3-A. Buffing Head

of deposition at the cathode. Utilizingan external source of current, is moreconvenient than producing the electro-types in the actual cell in a Daniell's bat-tery, except, if it is especially designedfor the purpose. This process is widelyemployed at the present time to repro-duce repousse and chased ornaments,works of art in fac-simile, and principallyfor the purpose of multiplying copies ofwood block cuts for printing.

The process of forming electrotypes isalso sometimes called metallizing. Tometallize a non-conductor, such as seal-ing wax, or rubber, some finely dividedmetallic powder, such as bronze powderor pulverized plumbago (graphite) isdusted over it. Before applying thepowder, the article or mould may, ifnecessary, receive a very fine coat ofwax. Metallizing may also be accom-plished by chemically coating such ma-terials as glass, or other objects toofragile to be treated in the manner usu-ally employed in electroplating, with sil-ver or gold by the ordinary chemical sil-vering or bronzing processes.

The following simple experiment is ofinterest:

Having procured a brass button, orother stamped metal article with a de-sign in relief, it is well soaked andcleaned with methylated spirit to re-move lacquer or grease. Now take apiece of cardboard and, holding it abovea Bunsen gas flame, but not igniting it,it is sufficiently warmed to melt good red

sealing wax. The wax may then berubbed into a pool on the úpper side ofthe card. An impression is now madeinto the wax, having previously breathedon the surface of the brass button justthe same as in regular wax sealing. Thedepth of the impression at the edge neednot be anything much below the centreof the edge of the button.

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If this has been done successfully, thecard is trimmed down, a few drops ofalcohol are put on the surface of thewax mould when fine powdered plum-bago is brushed over it by means of asoft camel's hair brush. The whole sur-face exposed should be thoroughly coatedwith the plumbago, finally brushing offall superfluous máterial.

Fig. 4. Primary Cell

The free end of the copper wire con-nected to the zinc electrode of the plat-ing cell depicted at Fig. 1, is heatedslightly and embedded in the sealingwax, with the point projecting just clearof the mold. Over this point a littleplumbago is brushed to complete theconnection to the face of the mold. Theprepared mold, with its plumbago coat-ing, is now to be suspended in the innerporous pot of the plating cell, Fig. 1, as

Fig. 5. "Electro" Type S.S. 6 Volt.4 Ampere Generator

shown, utilizing a weight to hold it downif necessary. The weight should be in-sulated if used.


Nov. 1914 THE ELECTRICAL EXPERIMENTER

The setting up of the plating cell (ofthe "Electro" make) is done as follows:

The glass jar and porous cup arewashed out, and the charge of blue stone

Fig. 6. Current Controller

(vitriol) is emptied into the porous cup,which is then filled to within 1/" of thetop with hot water, not boiling water.After letting it cool for ten minutes, themixture may be stirred with a woodenstick. Its color should be deep blue.The zinc cylinder electrode is next placedinto the glass jar, and same is filled witha solution consisting of twenty parts wa-ter and one part sulphuric acid. Theacid must always be poured into the wa-ter, and not vice versa, or else the con-tents of the vessel may be violentlyejected into the mixer's face. The por-ous cup with its solution is placed intothe zinc cylinder, noting that the heightof the two solutions are both the same.

The object to be plated is attached asseen, to the lower end of the copperwire held by the adjustable clip, allow-ing of raising and lowering it. Oncethe object is attached, it is lowered intothe porous cup and the plating begins.A very good deposit is obtained in fromten to fifteen minutes, on metal objects.The deposit, of course, is copper. Anymetallic object may be coated with it,directions for preparing and cleaningsuch objects being given fully a littlelater on.

To resume the subject of metallizingthe wax mould with its plumbago coating,it is lowered into the cell solution, withinthe porous cup. If by chance, the cur-rent is too strong, evidenced by burningof the copper deposit which manifestsits presence by dark brown smears andmarks around the edges, which shouldnormally be of pale salmon pink color,the zinc is suspended a trifle out of thesolution. The wax mould is left in theplating cell for approximately twenty-four hours, when it may be removed andstripped. If this does not occur easily,the wax can be melted off with slightheating applied. The electrotype maybe cleaned with methylated spirit. If anypin holes appear in the deposit, it ispractically certain it is due to imperfectdepositing of the copper, or to the pres-ence of loose plumbago on the surface ofthe mould. When the process has beensuccessful every detail of the original im-pression is reproduced exactly. If the

Fig. 7

specimen is to be preserved, a littlechloride of zinc may be brushed over thehollow back of the electrotype, having

previously cleaned the surface well. Asheet of tinfoil can be burnt on byspreading it over the surface and hold-ing the electrotype face downward overa Bunsen gas flame after which the bodyof the shell can be filled with molten tinor lead. The following current densityvalues are good ones, being given inamperes per 100 square inches of surfaceexposed. For copper electrotyping froman acid bath solution, best quality toughdeposit 1.5 to 4; good and tough deposit,10 to 25; solid deposit sandy at edges,25 to 40; sandy and granular deposit, 50to 100. For copper deposit from acyanide bath, 2 to 3; zinc, for refining,2 to 3; silver, 1 to 3; gold, 5 to 1; brass,3 to 3.5; iron (steel facing), .5 to 1.5;nickel, begin at 9 to 10 and graduallydiminish to 1 to 2.

For copper plating metal articles, suchas brass, iron, etc., the object shouldfirst be thoroughly cleaned. Begin byhanging the article in boiling caustic sodasolution for five to ten minutes, whichserves to remove all dirt and grease fromthe surface. Rinse the object in coldwater and it is then ready for plating.In case the object emerges from the plat-ing bath rough with fine holes on thesurface, it is most probably due, to in-sufficient cleaning; and it should be re-cleaned. Brass and iron objects shouldhe particularly well scrubbed with thehot caustic soda solution to remove alldirt from crevices, etc. When the plat-ing deposit has been made heavy enough,the article can be rinsed in cold water,

Fig. 9. The Ammeter or Current"Quantity" Gauge

and dried by rubbing with a piece offlannel, or by rolling in fine sawdust.The latter is the method usually em-ployed in all commercial plating shops.

Small animals, flowers, lace, etc., aremetallized by first cleansing in methyl-ated alcohol and while moist, they arethoroughly dusted with plumbago, fillingall the crevices and indentations. A wireis then fastened to any part of the objectand plumbagoed to the object to makeperfect connection. It is then suspendedinto the porous cup and the copper plat-ing begins. Very beautiful and artisticwork can be accomplished in this man-ner. A cut of the "Electro" copper plat-ing outfit is shown at Fig. 2.

For cleaning up articles preparatory toplating, a power head or buffer head, con-sisting of an iron standard with a shortshaft threaded to fit nuts at each end,and mounted with a driving pulley atthe centre, as seen in Fig. 3-A, is veryuseful. The buffing wheels employed forpolishing the plated articles are soft andcomposed of numerous discs of cottonflannel, sewed in circles and held on thebuffing head spindle by a flange plate andnut, as seen in Fig. 3-C. Scratch wheelswith wooden or wire bristles can alsobe fitted onto the buffing head as well asemery wheels, for preparing articles forplating. To drive the buffing head spin -

101

dle, a foot power treadle will be foundhandy if motor power is not at hand.A usual form of foot power drive isshown at Fig. 3-B.

Fig. 8. Water Motor for DrivingDynamos

For small plating work batteries canbe employed for the source of electricalenergy. Some form of closed circuit bat-tery is imperative, a good type being theGordon primary battery cell, depicted atFig. 4. These cells give about 7/10 volteach, and have enormous ampere hourcapacity ranging up to several hundredampere hours in the large sizes. Theyare suited to constant load and sufficientcells can be connected in series to givethe desired voltage. For some outfits, aplating dynamo may be more suitable,as when water power, etc., is available todrive it. A. suitable dynamo is depictedat Fig. 5. Plating dynamos, as a rule,do not deliver over 6 volts but 15 to 20amperes in small units, and they aregenerally shunt wound, viz., the fieldwinding is connected on multiple withthe armature brushes; series dynamosare too apt to be reversed by back E. M.F. from the plating tank, which acts asa battery. The "Electro" No. 810 andtype "S S" dynamos are suitable.

A useful variable resistance or rheostatfor controlling the amount or strengthof the plating current, is seen at Fig. 6.This rheostat permits of the finest reg-ulation and can carry 2 amperes forany length of time. It is connected inseries with one of the lead wires goingto the plating tank.

In preparing smooth finished articleson the flannel buffing wheel they are heldagainst it firmly, applying some polish-ing rouge from time to time to the wheel.Rough surfaces must be dressed downbefore attempting to plate them by filingand grinding on an emery wheel, finish-ing them on the flannel wheel with pol-ish rouge.

Having given these details considera-tion, attention may be turned to the sub-ject of nickel plating. The first part willdeal with a small nickel plating plant,such as that built by the Electro Import-ing Company. The illustration, Fig. 7,

Fig. 9. The Voltmeter or Current"Pressure" Gauge

shows their nickel plating set complete,with glass jar for holding the solution,nickel salts, etc.

(To be Continued)


lavAPY -rriiata cwis-rrtuc-rwi ,1121L1BUILDING AN OZONATOR.

Much has appeared in various mag-azines about electrical ozonators. Anozonator is an apparatus for producingozone. Ozone is a colorless gas havingthe odor of moist phosphorus. It canbe produced by means of electrical dis-charges.

The construction of a very efficientozonator is detailed here. It consists ofthree parts; first, the discharger; second,the'coil or transformer for producing theelectric tension; third, the fan for forc-ing the air across the gaps where theelectrical tension exists.

The discharger is made similar to acondenser. The articles necessary arenine glass -tubes, each having a bore orinside diameter of 3/16 inches and alength of about seven inches. Each tubeis sealed at one end by means of analcohol lamp. One end is left open.Nine brass rods, eight inches long by5/32 inches in diameter, each threadedfor 34 inches at one end only and eachrod is equipped with two nuts for con-nections. Also two clamps for holdingthe glass tubes a specified distance apart.viz., 1/16 inches. The tubes are thrustover the rods or vice versa.

Rods: The metal rods may be fas-tened on the tubes by mearis of someparaffine or wax. The first tube isplaced with the open end, i. e., with the

Brous rodi fann/h alb

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frq/ Dr3thorger

Mó/a-Genero/ Orrongemen/

nuts on, toward the right. The next onetoward the left, and so on. All rods andtubes are clamped evenly between theclamps as in Fig. 1. (In some case itmay be necessary to leave every otherglass tube out in order to produce a suf-ficient amount of ozone.)

The motor is equipped with a fan andplaced directly behind the discharger soas to force ozone out into the room. Thefan may be made of sheet brass or anyrigid metal. It is five inches in diameterand has four blades. It can be con-veniently fastened to the shaft of a motorby a small piece of wood or a tube (AFig. 2).

The discharger is connected as in Fig.1, the leads going to the transformer asassembly shows.

A safety gap should be placed in thecircuit if a transformer is used; connect-ing it across the secondary terminals ofsame.

This discharger may be connected toyour wireless coil already in use, but itis preferable to make it portable. Do notuse a transformer over 250 watts; 110watts is the best and any voltage trans-former may be used, i. e., over 5,000 volts.This set works admirably on 110 watt,13,000 volt transformer and fills a spaci-ous room with ozone in a very shorttime. If a spark coil is used, one giving

A SIMPLY MADE LOADING COIL.Here is a description of a neat and

efficient loading coil.The woodwork is made of one -quarter

inch hard wood and you need two pieces5" square; two pieces 10"x5" and twopieces 10"x4%". In Fig. 1, the blade is aNo. 5,000 E. I. Co. Rheostat blade costing10 cents, with a half dozen E. I. Co.switch points and the terminals are hardrubber binding posts. In Fig. we seea cardboard tube 5"x11" which may beprocured from the "Electro" people for

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25 cents and taps are brought out atevery two inches along the winding andare fastened to the switch contacts asshown. The tube is wound with No. 24B. & S. single cotton, or enameled mag-net wire. The drawings serve to makeeverything quite clear. This coil in con-nection with any ordinary receivingtransformer will tune to about 3,500meters.

Contributed bySTUART SANDREUTER.

IMITATION RUBBER BASES.All high class Radio instruments have

hard rubber bases. Amateurs often de-sire hard rubber instrument bases, butare held back by their high cost. Agood substitute is described below, whichis made comparatively cheap.

A hard rubber base of desired size isobtained and which should be but 4inch thick. The parts are mounted onthis base and then a hard wood base the

Nord rubberI Wood base

`..Coun/erborein mood

same size as the rubber base but aboutTA inch thick, is procured and holesdrilled in it in such a manner that noneof the metal parts touch the wood.

The next step is to paint the wood basewith a black shellac which contains ani-line dye, but no carbon. If aniline dyeis not available you can use thin blackasphalt paint. Of course the edges ofthe wood and rubber should be wellmatched before painting.

Contributed by W. R. COTTRELL.

a two or three inch spark, is preferred.All material mentioned here may be pur-chased of the E. I. Co. The motor maybe such as Nos. 100, 179 or 1880.

Contributed by J. NORDSTROM.

ELECTRICAL WEATHER VANE.Below you will find drawings as near

accurate and as clear as I can draw themof an out -door weather vane, whichregisters in your own room. The broomstick, in which is set the arrow, maybe of most any length and should beset in a six inch square wood block,not less than seven or eight inches high,which should have its lower end restingon a brass ball to let the rod turn veryeasily. On the rod is screwed an armwith an E. I. Co. slider secured at theend of it, as in the drawing, to makecontact with the commutator. This rodis connected with a copper ring at thebase as shown with a wire. The com-mutator should be constructed as fol-lows:

A wooden block seven inches squareand an inch thick with a hole six inchesin diameter cut from the center. Thebest way to do this would be on a latheas the whole secret lays in the perfectshape of this hole. Around the insideof this hole should be tacked four equallengths of very thin copper. Theseshould be tacked on with a small spacebetween them, about an eighth of aninch, and they should not touch as itwill cause a short-circuit. This com-

Broom handle "alb ski Ma- arrow

Schematic arrangement of electric WeatherVane indicator

mutator is held in place by strips fast-ened to the post to hold it firm. Fromeach section of the commutator, insu-lated wires are lead to lights with let-ters or names on them as in drawing.Now when the wind blows it will swingthe arrow, causing the broom stick toturn, thus connecting the slider with therespective segment of the commutatorand consequently lighting the light.which is connected with its respectivesegment. A switch may be put in thecircuit as in drawing, thus enabling thewind direction to be read at will.

Contributed byRANDOLPH ROLAND.

DISSIPATING FOG BY WIRELESS.The North Railroad company in

France is making experiments on theuse of wireless waves for clearing awayfog. It is well known that electric wavesmake up fog, so as to dissolve themand turn them into vapor. Followingthis idea, it is claimed that as much as600 feet can be cleared up in front ofthe electric wires which are sending outthe waves, the fog being at least par-tially dissipated, and this will have agreat value in practice, especially forrailroads and ships.

102



ELECTRIC LIGHT ON CANE.Imported canes and walking sticks are

often fitted with electric flash -lights forthe convenience of the owner, and theseare usually quite expensive of course.An electric flash -light cane is easily im-provised by any one, as shown in theillustration, and all that is needed is asmall 2% volt flash -light bulb, such asthe E. I. Co., supply, (No. 5,008 at 25c.) ;

Push bu//on

-Me/a/ Sleeve

-Lock

>2 ce// bolt.

a 2 cell battery No. 10,420 at 25c.; aminiature receptacle No. 1,052, some flex-ible silk -covered cord, and a small pushbutton, as No. 4,285, or this may be madefrom a piece of brass and a screw fora contact. The lamp battery and pushbutton are wired in series in the usualmanner. The cane, which should be afairly thick wooden one, is to be cutin two near the handle, and a 7/16"drill run down into the base section, toform a chamber for the battery of twocells, (placed end to end). The handlemay be joined to the base by a piece ofthreaded brass tube forced or threadedinto the wood of same, and also intothe cane base section. The flash -lightbattery here used comprises two cells,each about 7/16" by 2" long. The brassshell from the socket is removed fromthe porcelain or an "Electro" miniatureto candelabra adapter shell No. io,005may be utilized. The ingenuity of thereader will serve to arrange the canein a neat and strong manner.

ELECTRICITY FROM DUST.The curious experimental electrical

machine described by W. A. DouglasRudge to the Cambridge PhilosophicalSociety depends on dust.

When clouds of dust are raised-eitherby the wind or by artificial means-theyare always strongly charged with elec-tricity, which is positive or negative ac-cording to the nature of the material;and it is possible to obtain a continuoussupply of electricity by using suitableapparatus to drive a dust -laden streamof air thru an insulated tube.

While the dust is passing the tube willyield a steady stream of sparks, some-times more than two inches long. Theair escaping also carries a charge whichin a room may be retained half an houror more.

The charge is probably due both to theactual raising of the cloud and to frictionof the dust against the tube. Such dustmay be used as flour, sulphur, road dustor fine iron filings.

ELDON GARDNER, RADIOENTHUSIAST.

Eldon Gardner, son of R. D. Gardnerof Adams, Mass., has just completed awireless aerial 40 feet in height and 70feet in' length. It is suspended fromthe chimney on the house to the flagpole on the barn. He has a completesending and receiving set which he con-structed himself and with the newaerial he expects to receive messagesfrom 300 to 500 miles and send mes-sages about two miles.

A rising Marconi receiving wireless signals "a labedstead" according to the "Wireless World"

BOOK REVIEW."Experiments" by Philip E. Edelman,

Published by the author. 1914. 250pages, Profusely illustrated. Cloth.Price $1.50 Net. Postage 8 cents.

Mr. Edelman has given us an interest-ing treatise on Experiments in chemistry,electricity and mechanics, for those whoare interested in these subjects. Thereare 34 chapters in all, arranged in 2parts. The elements of applied experi-mental science are given in an interest-ing way with suitable illustrations. Highfrequency and wireless currents arecovered with data on spark coil con-struction up to 10 inch coils; Experi-mental aeronautics; microscopic photog-raphy; Electricity in Horticulture;Blow -pipe work; Novel Experimentswith glass, and many other inviting sub-jects.

QUEEN CITY RADIO ASS'N.Following the disbandment of the

L. W. O. of W. N. Y., the faithful mem-bers who still held together organizeda much better association. This newlyorganized association is to be known asthe "QUEEN CITY RADIO ASS'N."The club has a good start and we meanto take advantage of it. We hope tolive up to the motto we have chosen.

The aim of the club is to advance thenewly invented science among theamateurs in BUFFALO and vicinity andalso produce good fellowship among thefellows. The officers are R. E. Corts,Pres., Harold Capen, Vice-Pres., RolandHouck, Treas., Harold Stoeckel, Chief -operator, Lawrence H. Wolff, Secretary.The secretary will be glad to take careof any correspondence addressed to himat 63 Goembel Ave., Buffalo, N. Y.

103

IMPROVEMENTS IN LECLANCHEBATTERIES.

A note in a recent issue of the "Engin-eer" gives details of a French patentrelating to a primary battery of theLeclanche type, in which in the posi-tive electrode of dioxide of manganeseand graphite the graphite is replaced bylamp -black obtained from the decom-position of acetylene. When acted uponby an electric spark discharge, gaseousacetylene decomposes to hydrogen andcarbon, thus giving a chemically purecarbon. Its density is only 09, whilethat of graphite is 2.17 to 2.30. In thisway it is possible to increase the pro-portion of dioxide of manganese and ob-tain a more regular working of the cellthan with natural graphite whose com-position is variable. The finely dividedstate of the acetylene carbon is alsoclaimed to give a more intimate mixturewith the dioxide, and hence a betterresult. Another patent relates to amethod of working batteries of theabove type so as to use considerablecurrent from them and at the same timenot to run the battery down. The in-ventor treats the usual dioxide andgraphite mixture by adding to it an oxideof mercury, preferably red mercuricoxide, and in such case the output ofthe cell may be increased several timesand the battery can thus give heaviercurrents than before, while still maintain-ing the voltage. He further strengthensthe battery by using an alkaline electro-lyte, such as caustic soda or potash.

(The Electrician, London.)

ENERGY PROMMAINS IALTR. CURRENT

TO TRANSFORMERPRIMARY)

Ilieirnoyol R.oeoRonol uG.nnowé IRtione

EN.RGY IAISRI:S IN LO. _NR LO MIS LO ESTo WINDINGS& IN IN IN

TR.ANSMITrINO IRON CONDUCTORS DIELR TRICS SPARKANTENNA

ENERGY IN WAVESRADIATED

DIRECTION

,maiena¡ of promotion I

I:NERtIY IN WAVESREACHING RECS.

ANTENNA

1.05519 51ABSORPTION IN

AIRÍ... LORlER IN !DULL.tn

CURRENTS IN LOSSES INEARTH NEAR ANTENNA ANTENS_I

MERL' IN ENERGY INWAVES IN REQUIRED WAVER IN OTIlIAl

DIRECTIONS

LOSSES IllABRORPnON IN

SURFACE OPEARTH I SEA

ENERGY ABSORBED LOSSES DUE TOBY RECEIVING DAMPING

ANTENNA IHIAIWNU RESONANCUI

e SLuuny of antennamad N...,..iaw 'owning ...us) tm

I.NEWIY DELIVERED ENF.RG5 LOST JtRI1.RAN LO9RI:STO DETECTORINRE,RADIATION IN EARTH ANDWNDUCTORR

dnlurwr o/Smum

ENERGY PASSEDDN TO TELEPHONES

IA48ES INDETECTOR

Chart showing the successive losses occurring ina radio system.

(From Dr. W. H. Eccle's article in"Wireless World")

Following nine years' experiments withwireless and wire telephony, Dr. F. H.Millener, experimental engineer of theUnion Pacific, states that he has de-veloped his apparatus so that it is nowcommercially practical in all respects,and that a complete system of com-munication is ready to be installed onUnion Pacific and overland trains.


WJFL& DEI.F4L\Ftriqrm--Crystal Detectors and Electrothermal Action

By Dr. W. H. Eccles*

IN a paper to the Physical Society Dr. Eccles deals from anew theoretical standpoint with "Electrothermal pheno-mena at the contact of two conductors," and develops atheory of the action of crystal detectors.

In his introductory paragraphs he says:"When ,an electric current is caused to pass across the

interface between a pair of conducting masses, heat is in gen-eral liberated or absorbed in accordance with the law ofPeltier. When the masses are in contact over a very smallarea, as, for example, when a cylinder of graphite is laidacross a copper wire, there may be, in addition, appreciablegeneration of heat in accordance with the law of Joule. Ifthe substances constituting the contact are bad conductorsof electricity and of heat, and if they stand far apart in thethermoelectric series, the phenomena arising when a currentis forced across the joint become very striking, for in suchcircumstances relatively large amounts of heat may be de-veloped, the heat is conserved, and therefore the thermo-electric effects enhanced.

"It is evident that the thermoelectric forces called up bythe local heating may assist or may oppose the E.M.F. ap-plied to produce the current and that the phenomena of asymmetric conduction at once arises. But besides the Jouleand Peltier effects, the Thomson effect may contribute to thephenomena. In the case of bad conductors of heat the tem-perature gradients very near the contact will be very steep,and thus the Thomson effect will be localized in the imme-diate neighborhood of the contact.

"Further than this it is obvious that, on account of thetemperature changes, the portions of the substances nearthe contact will suffer a change in the magnitude of theirelectrical resistivity. It has been shown* that this effectalone leads to remarkable and important results and is suf-ficient to account for all the principal features of the single -point coherer used in wireless telegraphy.

"The thermoelectric forces and the changes of electricalresistance that arise from differences of temperature are muchgreater in combinations of such substances as iron pyritesthan in combinations of ordinary metals. A pyrites -leadcouple yields an E.M.F. some 200 per cent. greater than abismuth -lead junction, between the same extremes of (or-dinary) temperatures; while the temperature coefficient ofresistahce of pyrites is probably four times as great nu-merically as that of copper. But the thermal conductivityof pyrites is so very much smaller than that of lead that allthese thermoelectric phenomena are greatly accentuated inthe former case. Contacts between non-metallic conductorsare of special interest, for the reason that the bulk of thewireless telegraphy of the world is carried on by aid of de-tectors that consist of nothing else than a contact involvingat least one non-metallic conductor.

"The thermoelectric constants of such substances as py-rite, zincite, carborundum, etc., are not easy to measure ac-curately, and their coefficients of increase of resistance withtemperature are exceedingly difficult to determine. The au-thor has made numerous determinations, and has found thatall the materials examined follow with fair precision theordinary thermoelectric law that their thermoelectric powersare linear functions of the temperature, and also that theirtemperature -resistance coefficients are all large and negative."

The writer goes on to consider a circuit including a loosecontact, such as that formed by a piece of pyrites pressingagainst a piece of metal; the other junction making a verygood contact, so that its temperature remains unchanged.

"Let an E.M.F. be applied to the circuit in any manner soas to produce a current in the direction opposite to theE.M.F. that would be produced by heating the contact. Theheat liberated near the contact is, per absolute unit of elec-tricity flowing through the contact, equal to the thermoelec-tric force e plus the heat absorbed at the cold junction.

"This heat tends to be concentrated in a small volume ofthe substance near the contact, but is dispersed continuallyby thermal conductivity and radiation. We will assume thatthe rate of loss of heat by these agencies is, as a whole, pro-portional to the éxcess of temperature of the junction overits surroundings. The rise of temperature causes an altera-tion of the electrical resistance of the joint; let the true re-sistance at any temperature above the temperature of the

"Proc." Physical Society of London. Vol. XXII., p. 869.

surroundings be expressed by p (i+fO) where f is a tem-perature coefficient dependent on both the substances at thecontact."

His mathematical investigation leads to the obtaining ofan equation for the current y sent across a typical detector -junction, in terms of the P.D. (voltage) between the extremeends of the conductors which vary in temperature. If thisP.D. be represented by x, the equation obtained, omitting negli-gible terms, is

ax2y2+cxy2+bxy-x+py=o.The constants a, c, b in this equation are mainly dependenton the Thomson effect, the change of resistance with temper-ature, and the Peltier effect respectively. If the part of thecircuit which undergoes no appreciable temperature -changepossesses the constant 'resistance r, and the applied E.M.F.be denoted by e, then x = e - ry, and the steady currentcharacteristic curve as usually drawn from observations ofapplied E.M.F., and consequent current is identically that ob-tained by applying to the curve drawn from the above equa-tion of a homogeneous shear of amount r parallel to the axisof x.

The author proceeds to deal with particular cases in thisequation assigning various values to the constants a, c, andb, and showing the derived curves.

The paper itself should be consulted by all who are inter-ested in the subject; it is too long for a full abstract to begiven here. Among other interesting conclusions arrived at,it is indicated that when the constant a is positive, the cur-rent produced by a definite voltage is greater when the volt-age is negative than when it is positive; while when a isnegative or zero the positive produces the greatercurrent. Now, various writers (if we remember rightly, Pro-fessor Pierce in particular) discredit the theory that crystal -rectification is due to thermoelectric action, on the groundthat when some such contacts are warmed by direct com-munication of heat the thermoelectric force is in the oppositedirection to the current produced by the rectifying action.Dr. Eccles considers that this argument is a fallacy; for theobservation of the direction of the thermoelectric force pro-duced by direct heating shows only the sign of the Peltiereffect and not the sign of the Thomson effect in the circuit,and thus ignores the sign of the important constant a.

There is, we think, another argument against the thermo-electric explanation of crystal-action-the fact, obtained ex-perimentally, that the maximum current produced thermo-electrically may be thousands of times less than the rectifiedcurrent produced from an alternating current which givesrise to the same increase of temperature at the contact.

We do not know whether the experiment referred to wascarried out in such a way that the two cases could truly becompared, but we should doubt it, since the current producedby rectification would depend on what point of the curve wasbeing worked on.

We have submitted the above point to Dr. Eccles, and hetakes the same view, pointing out that his mathematical treat-ment shows that if the E.M.F. e is adjusted to a sharp bendin the curve, the rectified current might be enormous com-pared with the thermoelectric current. Thus things whichshow no thermoelectric E.M.F. may be good rectifiers, andhe quotes as an example a pair of pieces of galena, whichform a very good rectifier at a certain E.M.F. (aboutvolt), but which show no thermoelectric action.-Wireless World.

E. A. Strong of Winnipeg, Man., Canada, writes The E. I.Co. the following:

"I received the type 'S S' dynamo No. 1,331 in good order.I am well pleased with it and I must thank you for theprompt attention you gave my order and the prompt ship-ment also.

"As a motor, I think it is a wonder; such power for so smalla machine. I am using it as a generator driven by an induc-tion 110 volt A. C. motor and it sure is a perfect littlegenerator."

104


)tIk4 r.1J``1j J-`%11-rl b.E.I.Pi-Vnidta`'.This Department will award the following monthly prizes: FIRST PRIZE $5.00; SECOND PRIZE $2.00; THIRD PRIZE $1.00.The idea of this department is to accomplish new things with old apparatus or old material, and for the most useful, practical,and original idea submitted to the Editors of this department, a monthly series of prizes will be awarded. For the best ideas sub-mitted, a prize of $5.00 will be given; for the second best idea a 52.00 prize, and for the third best a prize of $1.00. The article neednot be very elaborate, and rough sketches are sufficient. We will make the mechanical drawings.

FIRST PRIZE, $5.00.

A USEFUL ELECTROMAGNET.By Henry G. Morrison.

An electromagnet is described belowwhich can be used for a variety of pur-poses, such as lifting, demonstrations,

3l'..- 4-1 ; :%4-ZOMoc/.fcrr,wiyrgf /ronYoke261-

' .---Fibrecheeks

r 1111113ICI

32

Eye

trrg7ironArmofl/rez"i

window displays, etc. The iron partsconsist of commercial wrought ironstock, procurable from any iron dealeror blacksmith. It should be soft annealedstock. The drawing shows the dimen-sions of the magnet frame and windingspools. These are made of %" fibre, hardrubber or wood discs of circular form,with holes drilled in the rear discs tobring out the leads from the coils, whichleads had best be made flexible so thatthe inside lead cannot be broken offeasily, which creates no end of trouble.

The coil bobbins should be wound fullof magnet wire and about 31b 5 oz. ofNo. 30 enameled copper wire is usedon the both spools; (total wire) for 110to 115 volts D. C. service. For batterycircuit the coils are composed of thesame amount of wire, but No. 20 S. C. C.or enameled wire is used. This considersabout 12 volts battery potential and 1.15amperes. If 6 volt battery current is tobe used on it then the two coils can beconnected on parallel, when the currentwill be twice the above of course, or 2.30amperes. On 110 volts the magnet isextremely efficient and takes but onetenth (0.1) ampere. Its maximum trac-tive or lifting effort is about 28 tbs. astested by the writer with the 115 voltD. C. winding. The resistance of the twocoils in series (No. 30 wire windings)for 115 volt D. C. service is 1,100 ohms.For the 12 volt winding the resistance isabout 10 ohms. The heavier wire hadbest be wound in even layers for high-est efficiency. The magnet cores be-tween the fibre and discs should be cov-ered with three layers of oiled linen orempire.cloth. Paper can be used for thiswork. Shellacking the coil gives a goodtough outer coating, but for the fine wirewinding the coils ought to be coveredwith paper or bookbinder's cloth to pro-tect the wire from damage. Enameledmagnet wires gives the maximum ef-ficiency as more turns can be put in agiven space than with any other insula-tion. The pole faces are tapered slightlywhere they make contact with the arma-ture, to increase the flux density at thesepoints.

SECOND PRIZE, $2.00.

MAKING A HOT-WIRE AMMETER.A Hot -Wire Ammeter is usually a

luxury beyond the purse of the averageradio amateur and the simple style heredescribed will undoubtedly be of interestto your readers. It is made up of anold alarm or other clock movement, asperceived, and all the wheels are removedexcept the balance wheel and hair-spring. To the top of the balance wheelis secured a pointer which deflects overa scale, calibrated to read in amperes,and fractions thereof.

To one side of the balance wheel isfastened a piece of silk thread whichends in a glass bead thru which passesthe heating element wire, which is.drawn between the two binding postson the case of the meter. The partsshould be so adjusted in relation to oneanother, that when no current passesthru the instrument, the pointer is atzero on the scale. The heavier the wire,the greater the capacity of the instru-ment, but to be accurate on high fre-quency or wireless currents, the wireto be heated by the current must bekept small. If the heating strand is tocarry the whole current and no shuntsare to be employed, as is the best prac-tise for this class of measuring instru-ment, then the heating element may hecomposed of several strands of No. 36B. & S. copper wire connected in multi-ple and those are preferably arrangedor mounted side by side and parallelwith a slight space between the strands,to allow of equal heating and coolingof each strand. The proper number ofstrands for a certain capacity in amperesis found easily by experiment and thecalibration is carried out on direct cur-rent, connecting this hot-wire meter anda regular D. C. ammeter in series. When

1 ampere shows on the scale of theD. C. meter then the point reached bythe needle of the new meter on its scaleshould be marked. In this way thewhole scale of the meter is calibrated,and a rheostat, together with a few bat-tery cells, etc., serve to give the neces-sary current valtes for the purpose.One of the small "Electro" ammetersis excellent for this work, as they arequite accurate indeed. Also a 16 C.P.carbon filament lamp on 110 VTS. D. C.passes about % ampere; A 32 C.P. 110VT. lamp passes about 1 ampere; Two32 C.P. lamps or four 16 C.P. lamps onparallel take about 2 amperes on 110VTS., etc. Of course the two binding

posts and the whole heating element ofthe meter are to be well insulated bymica or other washers placed aroundthe base screws of the binding posts.This principle here described will servefor making a hot-wire radio type am-meter for any capacity and also themultiple stranded heating element en-sures accuracy in the high frequencyreadings.

Contributed by H. CAINE.

THIRD PRIZE, $1.00.AN ELECTRO -CHEMICALPOLARITY INDICATOR.

The following is a description of asimple and efficient polarity indicatorwhich the writer has constructed and isusing with excellent results. The ma-terials needed are a glass tube, piece ofhard rubber and 2 switch points. Pro-cure some phenolphtalein and dissolveone tablet in 1 oz. water. Next add asmuch salt as the solution will dissolve.Cut a piece of glass tubing about threeinches in length and turn two pieces

Goss /WeAirbuó6/e, Nordrubber

disc`u= w' Srvi/ch point

,46243

jo/u//on ofphenophlho%inso//and wo%r

of IV hard rubber to fit tightly into tube.In the exact centre of each piece drilla hole exact size of shank of switch pointsand mount same on each side.

Fill tube with the solution and closeup ends by inserting rubber discs;leaving a small air bubble in the tube.Now any current passing through thetube will turn the solution near oneelectrode red. This is the negative pole.

I f the tube is tilted so that the airbubble comes in contact with the redpart of the solution, the red part willdisappear and the tube is ready foranother test.Contributed by J. L. GREEN.

RENEWING DRY CELLS.A worth while and inexpensive way ofrenewing old flashlight batteries is to

put a small amount of vinegar in the top,in which can be made a small hole toadmit the vinegar. If let stand a whilethe battery will be nearly as good asnew.

This may also be successfully appliedto old dry cells that have been discardedfrom automobiles, etc.

If this method is to be used on drycells it will be a good plan to drill twoor three holes about AT of an inch indiameter and as far down as possiblebeing careful not to pierce the bottom.Plug up the holes after recharging.

Contributed byLEO J. PRINDIVILLE.

105


PP rinklrs lrrripts Nrrrrnultts lintsBy S. Gernsback.

Under this heading we will publish every month useful information in Mechanics, Electricity and Chemistry.This department will be edited monthly by Mr. S. Gernsback.We shall be pleased, of course, to have our readers send us any recipes, formulas, wrinkles, new ideas, etc., useful to the experimenter,

which will be duly paid for, upon publication, if acceptable.

FORMULA NO. 3.Lacquerings for Metals.

Always apply lacquer with a good brushwhen the metal is warm, otherwise it willnot spread evenly.'

Black Lacquer -1 lb. Asphaltum, % lb.Lamp -black, / lb. Rosin, i qt. Spirits ofTurpentine. Dissolve the asphaltum androsin in the turpentine ; then rub up the lamp-black with linseed -oil, only sufficient toform a paste, and mix with the others.Apply with a brush.

(i) Japan Lacquer-All Colors.-i lb.Gum Sandarach, 2 ozs. Balsam of Fir, 2ozs. Balsam of Tolu, 2 ozs. Acetate of lead,/ pt. Linseed Oil, 2 qts. Spirits of Tur-pentine. Put all into a suitable kettle,except the turpentine, over a slow fire,at first, then raise to a higher heat untilall are melted; now take from the fire, andwhen a little cool, stir in the spirits ofturpentine and strain through a fine cloth.This is transparent; but by the followingmodifications any or all the various colorsare made from it.

(2) Black.-/ oz. Prussian Blue, 2 ozs.Asphaltum, / pt. Spirits of Turpentine.Melt the asphaltum in the turpentine; rubup the blue with a little of it, mix welland strain; then add the whole to one pintof the first, above.

(3) Blue.-Indigo and Prussian blue,both finely pulverized, of each / oz.;spirits of turpentine i pt. Mix well andstrain. Add of this to one pint of thefirst until the color suits.

(4) Red.-Take spirits of turpentine/ pt.; add cochineal / oz. Let stand15 hours and strain. Add of this to thefirst to suit the fancy.

(5) Yellow.-Take i oz. of pulverizedroot of - curcuma and stir of it into i pt.of the first, until the color pleases you, letstand a few hours and strain.

(6) Green.-Mix equal parts of theblue and yellow together, then mix withthe first until it suits the fancy.

(7) Orange.-Mix a little of the redwith more of the yellow and then with thefirst as heretofore, until pleased.

(8) Pink.-Mix a little of the blue tomore in quantity of the red, and thenwith the first until suited.

In this simple and philosophical wayyou get all the various colors. Apply witha brush.

Gold Lacquer for Tin.-Transparent, allcolors.-/ pt. Alcohol in a flask, add i oz.Gum Shellac, 1/2 oz. Turmeric, % oz. RedSanders. Set the flask in a warm place,shake frequently for 12 hours or more,then strain off the liquor, rinse the bottleand return it, corking tightly for use.

When this varnish is used, it must beapplied to the work freely and flowing,or, if the work admits of it, it may bedipped into the varnish, and laid on thetop of the stove to dry, which it will dovery quickly; and they must not be rubbedor brushed while drying; or the articlemay be hot when applied. One or morecoats may be laid on, as the color is re-quired more or less light or deep. Thisis applied to lanterns, etc. If any of itshould become thick from evaporation, atany time, thin it with alcohol. And bythe following modifications, all the variouscolors are obtained.

(2) Rose Color.-Proceed as above,substituting % oz. of finely ground, bestlake, in place of the turmeric.

(3) Blue.-The blue is made by substi-

CONTROLLING SPEED OF AMOTOR.

Many times it is desirable to controlthe speed of a battery motor such asthe "Electro" type "S S" 1/30 H. Poperating on 6 volts, from dry or stor-age batteries. This motor is shuntwound, i. e., its field winding is con-nected on parallel to the armature ter-minals. The connection of two No.5000 Rheostats for controlling the mo-tor speed above or below normal, is in-dicated plainly in our sketch reproducedhere. One rheostat is inserted in series

Tasurre+n/

with the armature circuit as at Rl;while the other rheostat at R 2, is inseries with the field winding. Thisenables the motor speed to be readilyraised or lowered in accordance withthe rule that weakening the field of amotor will raise its armature speed, andvice versa; also that speeds below nor-mal are obtainable by a variable resist-ance in series with the armature. It iswell to place a fused switch in all motorservice mains; or a couple of small E.I. Co., fuse blocks No. 918 may be usedon battery service quite effectually.

A SIMPLE GEISSLER TUBE.An incandescent lamp is connected to

one post of a "Bull -Dog" spark coil.The other post is connected to the top

of the globe, but does not have to be.When the current is turned on, a bluishglow will result which resembles theglow of a geissler tube.

Contributed byGEORGE F. STIMMEL.

A WATER WHEEL FOR DRIVINGDYNAMOS.

I recently spent a week in the countryand built a small water wheel whichdeveloped considerable power suit-able for driving a dynamo for electriclighting and thought I would describesame for the benefit of your readers.The drawing explains itself very well,and the brook was converged by awooden pile wall as shown or concretemay be advantageously employed toincrease the velocity of the water thruthe water wheel channel. The wheelmay be made large or small dependingupon the amount of water available andthe pressure; also the wheel blades may

be of metal or wood,and bucket shapedpaddles are of coursethe most efficient.

The pulley on thewater wheel is soproportioned that thedynamo will bedriven at the properspeed to develop itscorrect output. Therule for pulley com-putations is that thediameter of one pul-ley, times its speedi n revolutions p e r

minute, (R. P. M.) divided by thediameter or speed in R. P. M. of thesecond or other pulley gives directly themissing quantity for the second pulley;both pulley diameters being figured ininches. Many farms having access to alake or brook can in this way produceelectric lights without any maintenanceexpense, excepting the initial cost of theplant; including dynamo, storage bat-tery, etc., which are fully described andpriced in the E. I. Co.'s New Cat.No. 14.

Contributed by EDWARD MENNIE.(For a comprehensive article on Hydro -

Electric Plants of small size, with data onhigh pressure turbines of "Electro" make,see the May, 1914, "Electrical Experi-menter.")

f zmc ae ran plates /%/6%6

/' /Inv.(md©m

fichczr

Puller

tuting pulverized Prussian blue / oz. inplace of the turmeric.

(4) Purple.-Add a little of the blue tothe first.

(5) Green.-Add a little of the rose -color to the first.

Here again philosophy gives a varietyof shades with only a slight change ofmaterials or combinations.

Lacquer for Brass (Transparent). -1 oz.Turmeric root, ground fine, / dr. bestdragon's blood put into alcohol i pt. Placein a moderate heat, shake well for severaldays. It must be strained through a linencloth and put back into the bottle, and addpowdered gum shellac 3 ozs.; then keepas before in a warm place for several daysfrequently shaken; then again strained,bottled and corked tight.

106



THE "ELECTRO" MAGNETICCOMPASS AND ITS USES.

The "Electro" magnetic compass, simi-lar to all compasses of this type, consistsof a hardened steel needle, magnetizedand pivoted at its center, so as to freelymove over a calibrated scale, marked offwith the usual geographical points, suchas N. E. S. W. and intermediate points.This compass is extensively used in

The "Electro"S , , Compass

rig. 2

every day electrical work for variouspurposes, and can also be used of coursefor Orientation or the science of findingone's location.

Orientation consists of allowing thecompass needle, which is a magnet, tocome to rest and in doing so its North-seekinp pole or arrow -head will alwayspoint in the direction of the North Mag-netic Pole of the earth. The compasscase with its scale, should then be turneduntil the letter "N" on same is directlyunder the Arrow -head of the compassneedle; and of course it is then easy todetermine where E. S. and W. lie withrespect to the operator's location, whichmay be in the deep woods or in anypart of the country. This is the methodused for steering the large ocean ships,and also by explorers for laying outtheir journey, etc. See Fig. 1.

Testing magnetic polarity by meansof this compass is the commonest ac-curate way in which to test the polarityof a permanent or electro -magnet; inaccordance with the well known rule ofmagnetism; "like poles repel each other,while unlike poles attract one another."Accordingly, if the North (really theNorth -seeking pole of the needle, andactually its South pole, in accordance

-A -. Iwre

fí9.3

with the foregoing statement) pole ofthe compass needle is attracted by amagnet pole, then the latter's polarityís NORTH; and inversely, if the South-seeking pole, of the needle is attractedby a magnet pole, then the latters'polarity is SOUTH. This is the usualmethod of testing the polarity of thefield poles in motors and dynamos byelectricians. In the sketches here shownthe arrow -head on the compass needleis considered the North -seeking pole ofthe, needle, or in reality its South mag-netic pole; and likewise its tail is theSouth -seeking pole, or its actual North

-8-

magnetic pole. The various positionsassumed by such a compass needle in thefield of a steel horseshoe magnet isshown at Fig. 2.

Testing Live Wires by means of smallcompass such as this one is readily ac-complished by placing the compass eitherabove or under the wires carrying anelectric current as at Fig. 3; the needlewill then be deflected either to the rightor to the left, depending upon the posi-tion of the compass with respect to thewire, and also depending upon the direc-tion of the current thru the wires asindicated in the diagram. A magneticwhirl of field of force is present aboutevery electric conductor, and this iswhat causes the magnetic compass needleto deviate as shown. A piece of bellwire held over or under the compasswill cause it to be actuated even thobut % ampere passes thru same, asfrom an electric bell.

Making a voltmeter with this instru-ment can be effected by winding a num-ber of turns of the insulated mag-net wire, about No. 28 or 30 B.& S. gauge, about the center ofthe compass case, as indicated atFig. 4, so that the turns pass over thetop and under the bottom of the mag-netic needle, and parallel to its axis. Inusing the instrument so arranged, thecompass needle should be allowed tocome to rest naturally; or it may bebrought to a point of rest artificially by

w

E

Compass

Compass

N Moyne/ /eof eor/b

Fí9.4a small magnet placed near it. Thecoil of wire and compass case shouldbe turned until it is directly in line withthe needle. Now when an electric cur-rent is passed thru the coil, the needle willdeflect, and if quite a number of turnsare used in the coil the instrument willprove very sensitive indeed, and thusforms a simple and efficient galvano-meter, suitable for the testing of electriccircuits, spark coils windings, telephonereceivers, etc. By comparing the instru-ment so arranged, with a standard volt-meter, various deflections of the needle,with different currents passing thru thecoil may be thus checked up; so thatafter once making such a comparisonwith a regular voltmeter, such as thosesupplied by the E. I. Co., etc., futuremeasurements can easily be made withsame. It can also be calibrated withordinary dry cells, as these give quiteclosely, when new 1.5 volts per cell.Thus the deflection for 2 dry cells (largeor small) is 3 volts, etc. Fractions ofvolt deflections may be judged quitereadily in this way.

- -

A successful demonstration of wirelesstelegraphy at 100 words a minute wasrecently given in England by the Mar-coni Company between Chelmsford andLetterfrack (Galway).

107

HOW TO RECHARGE DRY CELLS.First remove the cardboard wrapper,

then with a piece of emery cloth cleanthe zinc covering. Next with a drillpierce holes round the cell and all theway down making the holes about 1 in.apart. The perforated cell is then putin a 2 -lb. glass jar with water and 3 ozs.of sal -ammoniac. This makes an efficient"Leclanche" cell, and will give from 1to 1.5 volts according to quality of drycell. If zinc covering is badly eatenprevious to perforating wrap a piece ofmuslin round it; and make the zincconnection from an ordinary cylindricalzinc, as used in Leclanche cells.

The above cell will give voltage men-tioned until zinc casing is completely -eaten away.

Another method is as follows: Pro -

Zinc Coveringof Dry Ce//

No/es about1st" deep

cure a machine drill of. about 4" to3/16" in diameter and drill holes carefully till the drill touches the carbon.Do not be afraid to drill through theentire portion of the depolarizer, as itis necessary that it gets air and electro-lyte. It is obvious that drilled holesdo not throw up a rim, but leave a flat,clean hole, making short circuit entirelyout of the question. We would recom-mend to drill about 8 or 10 such holes,being careful to see that all manganese -

(black filler) is carried out of the hole.Blowing hard in the hole will usuallyclear it perfectly. We also recommendto drill each hole as rapidly as possible,because the drill .itself, being in contactwith both zinc and depolarizer during -

the act of drilling, for the time shortcircuits the cell.

Next prepare a solution of 10 parts.(by weight) water and 5 parts of chloride-

of zinc, which can be bought for about50 to 60 cents per pound. Ten cents.worth will do for about a dozen drycells. If the solution is kept in a wellstoppered bottle it can be used over andover, as each cell does not absorb muchliquid.

The solution must be well heated be --fore used, but should not boil. Insertthe cell in this liquid and leave in same -for about 20 to 30 minutes. The cells.should then be taken out and rolled onthe floor. Each hole should now beinspected to verify if it is clean and ifno filler touches the zinc.

Now dry the cell carefully, and ifpossible insert in each drill hole a drywooden plug, which can be cut off flushwith the zinc.

The battery is now ready for use andin most cases will register from 8 to 12'amperes and about 1.3 volts.

A. B. Tyrrell, of Medford, Mass.,,writes the E. I. Co.:

"The instruments I purchased fromyou some time ago are working per-fectly. I am more than pleased withthem and would advise any amateur orprofessional looking for good instru-ments to purchase the E. I. Co.'s as.they do the work. Will favor you withan order in the near future."


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THERMOSTATIC CIRCUIT -CLOSER (Fig. 1)-Really a thermometer withtwo electrical leads mounted in the walls of the tube, so that widue heatcauses the mercury to rise and short-circuit the sealed -in leads ringing abell, etc.

BATTERY LAMP MOUNT (Fig. 2)-Readily attached to any dry cell;lamp arranged on a metallic cap slipping over the paper carton of battery.

TELEPHONE TRANSMITTER (Fig. 3)-Improved transmitter having itsdiaphragm resiliently mounted to minimize distortion of the voice.

AUTOMOBILE SIGNAL (Fig, 4)-Electric lamps illuminate nal orstop signs; a colored light being thrown on movable signal arm when it israised. When the arm falls colored light goes out and signal sign lamplights.

DRY CELL (Fig. 5)-A dry cell (so-called) containing a liquid lectro-lyte with the negative electrode suspended in same. The outer u 1 shellforms the positive electrode, and the whole is hermetically sealed

' SANITARY MOUTHPIECE (Fig. 6)-A telephone mouthpiece designed tohave a liquid disinfectant held in an absorbent between the perforated wallsof same.

ANOTHER ANTISEPTIC MOUTHPIECE (Fig. 7)-The powdered anti-septic is held in an absorbent annular chamber, with perforated walls, andthe whole device is made attachable to any telephone mouthpiece

ELECTRIC SHEARS (Fig. 8)-A simple electric shear using a hand con-trolled switch and a suction or solenoid magnet to actuate the blades.

ELECTRIC DISINFECTANT DISTRIBUTER (Fig. Si-Disinfectant holderarranged to be mounted in front of a desk fan, and fumes from same to bethus blown outward with the air draught.

FLASH -LIGHT (Fig. 10)-A removable lamp, switch and handle ar-ranged to fit on any common dry battery, and made of 14 -inch metal strip.

k9

4

ELECTROLYTIC INTERRUPTERSAND HOW TO USE THEM.

By H. Winfield Secor.Electrolytic interrupters are widely

used for operating X-ray spark coils andwireless coils, etc., but do not alwaysgive the best of satisfaction, and justwhy this is so is explained briefly below.

It has been found in practice, andseveral authorities, including Dr. J. A.Fleming, in his excellent work, "ThePrinciples of Electric Wave Telegraphy,"state that the self-inductance (not re-sistance), of the circuit connected inseries with these interrupters is not al-ways sufficient to properly operate same,and if no inductance is included in thecircuit the interrupter will not work atall. This is quite an important matter,and is frequently lost sight of by theuser of such apparatus. Besides increas-ing the working qualities of the inter-rupter, an adjustable reactance (such asa choke coil), connected in series withthe circuit containing the interrupterpermits of limiting the current passingin such a circuit, and this is essentialto prevent flickering of the lights onhouse -lighting circuits, which trouble isoftentimes very pronounced.

The electrolytic interrupter when con-nected in series with the primary wind-ing of a good % kw. transformer coil(of the open core type; closed coretransformers cannot be operated by it),should draw from 5 to G amperes. The

circuit voltage may be from 50 to 110volts, A. C. or D. C. The A. C. fre-quency should not be lower than50 cycles, and better 60 cycles. Thesolution for the interrupter is com-posed of 5 parts pure water and 1 partof pure sulphuric acid. In mixing theseingredients, the acid should always bepoured into the water, and not vice -versa,as otherwise the solution is liable to beforcibly ejected from the containing ves-sel. The frequency of the interruptervaries with the amount of inductanceand voltage of the circuit, and sometimesreaches a value as high as 7,000 inter-ruptions per second, as compared to twoor three hundred per second, obtainedfrom ordinary spring vibrators.

In cases where the interrupter fails towork satisfactorily, or passes too muchcurrent, a choke coil is generally thesolution of the problem. Such a coil iseasily made for ordinary purposes, byusing a soft iron wire core 8 inches longby 1 inch in diameter, the weight beingabout 1.33 pounds. This core should beinsulated with three layers of Empirecloth or shellacked paper. Over theinsulated core is wound 3 layers of No.14 B. & S. gauge enameled or D. C. C.copper magnet wire (about 2 pounds isrequired); leading taps off from eachlayer so that the self-inductance in cir-cuit may be varied by connecting toone or more layers as required. It isbest to arrange the iron core to be movedin and out of the coil, which gives a very

wide range of reactance adjustment.When the electrolytic interrupter is em-ployed the spark coil vibrator shouldbe cut out by screwing up the contactscrew tight; or short circuiting the vi-brator with a piece of copper wire.

Another easily remedied trouble withelectrolytic interrupters is that of heat-ing, the solution often becoming veryhot especially where X-ray coils areoperated steadily for long periods. Theremedy for this trouble is to form acooling worm out of thin lead pipe,having an inside diameter of % to 11inch, and the worm may have 4 to 6convolutions. This pipe worm shouldjust fit nicely into the interrupter jar, soas not to interfere with the working parts.Cold water is circulated through theworm by attaching one end cf it to anordinary spigot by means of a piece ofrubber tubing, and the other end of theworm is connected with a piece of rub-ber tubing to a sink.

An easier way, but not as effective,is to place the interrupter jar within alarger vessel, and circulating cold waterthrough same. This outer vessel is prob-ably best composed of metal, as it is thenan easy matter to provide a waste out-let by soldering a small piece of brasspipe into the side of the vessel, near thebottom. The water is fed into the topof the container, and thus a steady cir-culation of cool water is maintainedabout the interrupter jar,-Reprinted fromJanuary, 1913, issue of Modern Electrics.

108AmericanRadioHistory.Com

A01 OP1 :J 1-1 iJfUrtAMATEUR RADIO STATION CONTEST.

Monthly Prize, $3.00.This month's prize winner.

WIRELESS LABORATORY OF W. MORRISH.I am so glad to see you are starting to publish photos

of wireless stations in The Electrical Experimenter. I am en-closing a photo of my wireless station. My receiving setconsists of tuningtransformer, d o u -b l e slide tuningcoil and a loadingcoil, with -galenadetectors, variableand fixed condens-ers and 1,000 ohmMurdock phones.The aerial has fourwires, 60 feet long,suspended on twopoles; one 40 feethigh and the other32 feet. My groundis of iron buried inthe earth. I amquite satisfied with

my receiving set. I can hear W. S. L.; N. A. A.; Cape Cod,and many nearby stations. My sending set consists of anautomobile ignition coil, condensers, spark gap, helix, bat-teries and key. I can transmit about two miles. I have anamateur's Government license, but at present we are all sus-pending operations on account of the war.

Yours truly,W. MORRISH,

Gravenhurst, Ontario, Can.

GEORGE RIEGER'S RADIO OUTFIT.Here is one view of my wireless station.A one inch spark coil is seen on the left hand side of the

picture. In front of this is the spark gap, which I made, andin back of the spark coil is a glass plate condenser. In thecenter is the aerialswitch and on theright hand side, alittle to the frontof the picture, is aMesco key. Backof this is the tuningcoil with two slid-ers and in front ofthis a variable con-denser.

The detector isto the right of thevariable condenserwhich is of silicontype and a fixedcondenser is usedalso. I also have a buzzer test.

A pair of 75 ohms receivers are laying on the left handcorner of the table. The Electrical Experimenter is enjoyed bymy brother and myself every month. I don't see how you canpublish it so cheap.

GEORGE RIEGER, Jr.,Penllyn, Pa.

WIRELESS ON DELIVERY VANS.Motor delivery vans of one of London's largest tobacco

firms have been equipped with wireless apparatus in orderthat help may be rushed to needy smokers on the receipt ofthe signal S. O. S., meaning, "Send on Smokes."

This firm claims to be the only one in the world using thewireless in its delivery system. The firm communicates thrua station on the roof of the building. Aerials are placed onthe vans, manipulated by an operator inside.

W. R. Hughes, of Vonore, Tenn., writes the E. I. Co.,N. Y.:"I have bought several dollars worth of wireless goods

from you. I have your 3000 ohm receivers, and I hear Say-ville, N. Y., 'N. A. A.,' and several other stations, mostlyevery night, and some days, with a galena detector."

U. S. WIRELESS TRUCK HAS 800 -MILE RANGE.Remarkable advance in the construction of portable wire-

less sets for army field service has been made by the SignalCorps of the United States Army. For the next field opera-tions of the army there is available a wireless truck whichcan be set up for use in twelve minutes and send messageswithin a radius of 800 miles under favorable conditions.

The truck was built especially for the Signal Corps by theWhite Company, of Cleveland. In tests that have alreadybeen made this set has received messages from points 2,500miles distant. The electrical pressure reaches 90,000 volts atthe top of the antennae. The great range of the new equip-ment and the speed with which it may be brought into actionis due to the employment of a powerful electric generatordriven thru a train of gears by the thirty -horsepower motorof the White truck.

The generator delivers electric current of 500 cycles at 110volts and from eighteen to thirty-two amperes. This currentis interrupted by the relay, operated by the sending key, andis transformed so that it leaves the sides of the wireless truckat a pressure of 22,000 volts and an amperage varying fromeight to twelve. As the current rises to the top of the anten-nae the voltage rises to approximately 90,000 while the am-perage approaches zero.

The radiation under these conditions gives a sending abil-ity from 200 miles under the worst conditions in day timeup to 800 miles under good conditions obtained in the earlyhours of the morning when there is less electrical disturbancedue to electrical plants of various kinds.

The antennae is of the umbrella type, mounted at the topof an eighty -five-foot mast which is built in nine sections.The first, or top, section is raised by hand but the other sec-tions are lifted by a block and tackle suspended from strutsmounted on a platform on the roof of the truck.

Anent The "Radioson Detector."Harry Fostrom, of Indianapolis, Ind., writes the E. I. Co.,

under recent date:".I received the `Radioson Detector' cartridge you sent me,

and it is all right. Have tried it out and find it works well."

C. R. Cutter of Melbourne, Victoria, Australia, writes us:"The little 'Electro' set I bought from them in 1910, isstill doing good service and it has played its part in gettingthem considerable business from several parties in Mel-bourne."

32,000 H. P. TURBINE.The Westinghouse Machine Company of Pittsburgh, Pa.,

has received an order from the Edison Electric IlluminatingCompany, of Brooklyn Borough, New York, for the largeststeam turbine engine of the single unit type that ever hasbeen constructed.

This engine will be rated at 32,000 horse power and willbe used for the generation of electric current to furnish elec-tric light and power.

. INSTALL WIRELESS AT CAMP GROUND.An important side of modern warfare is emphasized at

the second brigade camp at the Joe Hooker campgrounds,Lakeville, Mass., by the practical work of Capt. Harry G.Chase. A wireless station was erected by the corps at thefarther end of the field, and baseball scores, horse racing re-sults and general business notes and bulletins of news werereceived by this means. In fact, the operator was in touchwith Wellfleet station, Siasconset and Charlestown, and fromthe station near the Middleboro railroad station orders weregiven and sent to headquarters at camp.

MELTING POINTS OF METALS.The melting points of some metals which fuse at very high

temperatures are published by G. K. Burgess and R. G. Wal-tenberg in the "Journal of the Washington Academy ofScience." The melting points are as follows: Titanium, 1795°C. (3,263° F.) ; vanadium, 1,720° C. (3,128° F.) ; chromium,1,520° C. (2,768° F.) ; manganese, 1,260° C. (2,300° F.) ; iron,1,530° C. (2,786° F.); cobalt, 1,478° C. (2,692° F.); nickel,1,452° C. (2,545° F.)

Donald Harris, of Deep River, Conn., has installed a verycomplete and up-to-date wireless outfit in the rear of hishome which is affording him plenty of amusement duringhis summer vacation. Harold French is also experimentingin wireless telegraphy.

109


c?).Jezia si I rjThis department is for the sole benefit of the electrical experimenter. Questions will be answered here for the benefit of all,

but only matter of sufficient interest will be published. Rules under which questions will be answered:1. At least one of the questions must deal with "E. I. Co." apparatus or instruments, or "E. I. Co." merchandise.2. Only three questions can be submitted to be answered.3. Only one side of sheet to be written on; matter must be typewritten or else written in ink, no penciled matter considered.4. Sketches, diagrams, etc., must be on separate sheets. Questions addressed to this Department cannot be answered by mail.

BATTERY SOLUTION.(178.) Norman Henning asks:Q. 1. Where can I find a price list of E. I. Co. chemicals,

and also how much Bichronate of Potash should be used toa pint of dilute sulphuric acid in batteries to prevent polariza-tion, and to increase the voltage to 2 volts?

A. 1. In reply to this query, would refer you to the Janu-ary, 1914, Electrical Experimenter, and prices of chemicalsare listed therein which the E. I. Co. supply and no orders forless than $1.00 worth of chemicals are accepted.

In regard to your battery solution inquiry, would say thatthe usual mixture for this solution is as follows:

5 parts water, 1 part sulphuric acid and 2 parts Bichromateof Potash, by volume.

SMALL DYNAMO TROUBLES.(179.) Chas. C. Haddock, Burkehaven, Lake Sunapee,

N. H., complains of trouble in operating an "Electro" No.810, 8 volt, 10 ampere, D. C. shunt wound generator, etc.

A. 1. We would suggest that the armature in the No. 810dynamo may be driven in either direction usually, and if itdoes not generate promptly upon driving same in say onedirection, it may be reversed, or also the shunt field con-nections may be reversed so that the machine can build upproperly from its residual field magnetism.

In case the machine should fail to generate at once aftertrying the above, a few cells of battery may be connected inseries with the shunt field winding for a few minutes, to mag-netize the field magnet. The positive and negative pole maybe ascertained by means of pole test paper; or also by placingtwo wires connected to the terminals of the machine into aglass of salt water, and the wire giving off the most bubblesis the negative wire.

INDUCTION COIL CURRENTS.(180.) James L. Green, Rosser, Manitoba, Canada, writes

us about the action of induction coils, etc. We advise him asfollows:

A. 1. Replying to your communication in reference to astatement regarding the action of induction coils as made inDr. J. A. Fleming's book, "Principles of Electric Wave Tel-egraphy," would say that this statement is correct, and allinduction coils frequently produce alternating current, butof course it practically never approaches anything like a truesine wave form.

\Ve refer you to the July, 1914, Electrical Experimenter,which covers this subject in detail, and also some oscillo-graphic curves are there given, as reproduced from a smallspark coil and also from a medical coil. The ordinary smallmedical induction coil, which does not have any condenseracross the vibrator, produces a fairly strong inverse or vi-brator MAKE current; but, however, the vibrator BREAKcurrent is always the more pronounced, and very markedly soin the case of spark coils of course, due to the action of thecondenser across the vibrator, etc., and the spark dischargefrom induction coils is always of d predominating polarity;and this may be tested in several ways as explained in thearticle aforementioned; and for small medical coils a low volt-age polarity indicator such as the liquid or chemical papertest can be used to ascertain the polarity of the secondarycurrent.

It is very difficult for us to judge what branch of ElectricalEngineering you would prefer to follow and this is always amatter of individual or personal judgment. It is also very dif-ficult to answer your third question, as to which is best toutilize for general experimenting, i. e., a 1 K. W. closed corestep-up A. C. Transformer or a 10" spark coil, but the Editorin general would prefer the 10" spark coil.

RADIO INSTALLATIONS.(181.) P. G. S., Jr., Boston, asks:Q. 1. Please give instructions for setting up and opera-

ting types S. O. 200 and R. O. 2,000 E. I. Co. Wireless Tele-graph sets.

A. 1. We are pleased to advise you as follows:Aerials.

The aerial for this set should be of the horizontal or in-clined type and have an average elevation above the groundof 100 to 125 feet. The aerial wires are spaced 3 to 4 feetapart, and are best composed of No. 14 Antenium wire orstranded cable, with insulators placed at the end of eachstrand. The lead-in wires are spliced onto the aerial strands

at one end, and a few feet below the aerial they are joinedinto one heavy wire forming the lead-in wire; and this is ledto the blade of the lightning grounding switch, so that whenthe blade is thrown to the grounded jaw, the aerial is effect-ually grounded; which should always be done when the sta-tion is not in operation or during electric storms. The lengthof the aerial may be 100 to 150 feet. All joints on the aerialfor best results should be soldered with a non -corrosive fluxsuch as resin or "Solderall." Great care should be exercisedto see that the aerial wires and the lead-in terminals are care-fully insulated, so that the high voltage sending currentsfrom the transformer does not leak away, instead of sendingout wireless waves.

Transmitting Instruments.The connection of the various transmitting instruments

will be readily perceived by looking at the blue -prints fur-nished with them, and the primary source of energy may be110-220 volts A. C. or D. C. and about 15 ampere fuses andknife switch, should be placed in the primary feed wires.Ground connections for the kick -back preventer should bemade to a separate ground terminal. Considering the highvoltage sending circuit, which is supplied with a voltage ofabout 50,000 from the 21A K. W. transformer coils No. 8050,it is seen that the plate glass condenser is connected acrossthe transformer coil secondary terminals. The adjustablespark gap of the set in series with the primary winding of theoscillation transformer is connected across the plate glasscondenser previously mentioned; and the wave length of theclosed oscillating circuit is varied by moving the contact onthe primary coil. The secondary winding of the oscillationtransformer connects to the aerial and ground thru theaerial switch; connecting the hot wire ammeter in series withthe aerial lead. In operating the transmitter the spark gap inthe closed oscillating circuit is always quite short and aheavy loud blue -white spark should occur in same, the lengthof the gap being about S to 3/16 of an inch in most cases.The transmitting set is tuned by adjusting the contacts onthe primary and secondary of the oscillation transformercoils; until the loudest spark occurs in the spark gap and thehot wire ammeter registers a maximum deflection, whichdenotes that the set is in tune, and that it is radiating maxi-mum power. The No. 8100 aerial switch is thrown forwardfor transmitting and backward for receiving.

The Receiving Set.The receiving set employs a loose coupler or receiving

transformer and the slider terminals of the primary or outerwinding are connected to the rear terminals of the aerialswitch as shown in the blue prints furnished. The two sec-ondary or inner coil terminals are connected to the variablecondenser No. 3500 and also to the rest of the receiving setas indicated. The small Jr. Fixed condenser No. 10010should be connected with a switch in series with it as shown,so that it may be disconnected from across the telephone re-ceivers, as it is only in rare cases that it is necessary. Thetuning of the receiving set is accomplished by adjusting theposition of the sliders on the primary coil, and also by mov-ing the secondary coil in and out of the primary coil; aswell as by alternating the secondary circuit inductance. Atthe same time the capacity of the variable condenser No.3500 is adjusted and this in some cases is used connectedacross the terminals of the primary winding. The incomingtelegraph code signals are heard in the telephone receivers asshort and long buzzes, and can be deciphered by any tele-graph operator knowing the code used, and the standardMorse radio code is the one in general use.

PLENTY OF ELECTRICITY.In the concluding part of a recent address before the wire-

less society of London, A. A. Campbell Swinton, speakingof the wireless transmission of power, first referred to thestrong belief of Messrs. Tesla and Penderson in its future,and then called attention to the fact that on a clear day theearth receives from the sun no less than 4,500,000 horsepower to each square mile of surface. This enormous supplyof power comes in the form of. electro -magnetic waves andvia wireless. Evidently, therefore, there is no doubt as tothe possibility of transmitting stupendous amounts of energywithout wires. Regarding the possibility of using thiscarrier efficiently for any other purpose than that of simplecommunication, Swinton seemed skeptical.

110


Nov. 1914 THE ELECTRICAL EXPERIMENTER 111

ELECTRICITY AND LIFE.The human body is an electrical machine. It, together with

all the intelligence it has ever had, or ever will have, camefrom the sun. Permeating the universe, being in fact theuniverse itself, is one supreme principle. This principle maybe called God, or the soul, or the supreme power, or anythingelse that you wish to call it; but within it, and it alone, lieseverything that the human mind can conceive of and count-less other things as well. It is the power, wisdom, andbeauty; the all in all, the Existence itself-there is nothingelse beside. There are not two or more, there is but one.Everything that exists is but a manifestation of it. Thisprinciple, for the want of a better definition and to get itwithin the range of the human mind, will be called sun -power,because the sun appears as its first seat in the natural uni-verse. In the sun it separates itself into TWO and appearsas electricity.

The TWO appear as ONE, being electricity, having twoopposite qualities, positive and negative. The positive andthe negative bear within themselves the law of attraction andrepulsion, without which no form can live. The positive cur-rent of electricity is acid, the negative is alkaline, and thesetwo principles stand at the head of chemistry exercising au-thority over action and reaction, thus directly giving rise tothe phenomena of matter and their countless changes.

The method whereby worlds are built is that a magneticor electric center sets up and connects with the sun. Theinstant this connection is formed, a stream of positive elec-tricity flows from the sun to the newly formed magneticcenter and this river of electricity carries with it the elementsand matter which are deposited at the magnetic center whenthe current becomes negative and starts on its return to thesun. Chemical action then sets up and as ages go by themagnetic center becomes filled in with minerals and otherforms of life until a vast and complicated productivity ofliving forms has been evolved. How really little solid mat-ter is in existence may be inferred from the fact that thecremation of the human body leaves an insignificant residue,while the burning of a large oak tree, would leave but com-paratively little ashes. This disappearance of bulk is but theretreat of matter into its more volatile forms, forms approxi-mating perhaps those utilized by it in its interplanetarymovements. The very seas themselves, vast as they are,may readily be rendered invisible to our eye and their bedsleft bare, thus showing that seas are not necessarily perma-nent in nature since provision for their movement has beenprovided. Indeed, the seas, as well as the rest of the earth,flows from the sun upon an electric current and if they everdepart from this globe they will leave it in the same wayand they will go to the sun or to whatever other electriccenter the earth may be connected with. The sun is themaster distributor of electricity in the solar system and elec-tricity is the only form of transportation and communicationbetween the sun and the planets.. The sun draws in the elec-trical energy from space and from exchanges with planetsand sends it out in definite, direbt streams to planetary bodies.A planet is a magnetic center, negative to the sun. Itsdensity is the result of being filled in with matter fromchemical action and reaction, arising itself from the acid andalkaline poles of the positive and negative current which con-nects it with the sun, its distance from the sun depends uponits density, the more solid planets being near the sun. Agaseous planet assumes a point remote from the sun towardwhich it moves as it is filled in by chemical action and as-sumes density, because the density is brought about by min-eral deposits and other chemical creations which make theplanet more attractive to the sun.

The sun is not, therefore, a ball of fire, as has been sup-posed, but it is the center of electrical energy and it may bea very inhabitable place.* The influence that the sun exercisesupon living forms would indicate that our vital origin isresident in sun power and that we arrived on this planet ina stream of electricity that constantly flows from the sun tothe earth. If this theory is true, and it has much more torecommend it than most of the superstitious vagaries thatoccupy the human mind, then it is true that our real natureis one of High Power and that our ultimate destiny is onewhich our quondam gods might well envy. For then, withthe intelligence that research will give, will come the powerof inter -planetary travel and all that it implies. And withthis, too, comes the knowledge of chemistry in life processesthat will enable us to detach ourselves from a material bodyon one planet make the trip and instantly assume anotherbody suitable to existing conditions upon another globe, in-stead of, as perhaps at present, being obliged to await theslow process that natural law has provided for the period ofunconscious evolution.-"Riches."

"(Indeed??!! Ed.)

ELECTRICITY ON THE FARM.It is estimated that there are at least 2,000,000 gasoline and

oil engines on the farms in this country at the present day,and this number is being added to at the rate of 500,000 annu-ally. The average size of these engines is about seven horse-power.

A great many farmers who have already installed enginesfor power purposes would also like to have electric lights forthe house and farm buildings and other electrical conveni-ences, but do not know how to go about it to secure thenecessary apparatus.

The necessary auxiliary apparatus consists of a smallelectric generator, a storage battery and the necessary wiringand lamps. The generator is belted to the gas engine andrun until the storage battery is charged; then it is stoppedand not started up again until necessary. Generally, two orthree short runs during the week will be sufficient, and evenless where only a few lamps are used at a time.

A COMPLETE GALENA DETECTOR FREEHere is what we give you-Solid black fibre base 1%"xli4".

A piece of sensitive Galena mounted in the nickel detectorcup. This cup is also a binding post and the connecting wireis fastened by means of set screw. Sliding nickel rod is em-bedded in solid hard rubber handle %" in diameter. At theother end of the rod is fastened the phosphor bronze "Cat -Whisker" wire. The sliding rod slides in the nickel springstandard, which also forms a binding post at the same time.

No matter if you have a dozen detectors, you will want thisone. It is the neatest little instrument you ever saw and itworks as well as a $10.00 one.

Given FREE with one year's subscription to The ElectricalExperimenter. Price In U. S. and Canada, 50c.; Foreign, 75c.

"THE ONE ELECTRICAL MAGAZINE YOU CHERISH"

GALENANICKEL

DETECTORCUP ANOBINDINGPOST

SOLIDFIBREBASE

HARD RUBBERHANDLE

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aoz BINDINGPOST

MADE IN U. S. A.

WIRELESS AND ELECTRICAL BOOKS.We have on hand the following books of interest to every electrical and wireless

man, and any other hooks on these subjects you are interested in, will be quotedupon request.Uses of Electricity on Shipboard, (Kellogg) $1.00A. B. C. of the Motorcycle 1.00Wireless Telegraphy, (Sewell) 2.00Radium, (S. R. Bottone) .50Electrical Apparatus 1.00A. B. C. of the Telephone, (Romans) 1.00A. B. C. of Electrical Experiments, (Clarke) 1.00Electric Bells and All About Them, (Bottone) 1.00A. B. C. of Electricity 1.00Induction Coils, (Trevert)Radiography, (Bottone) .50Electric Light for Country Houses, by Knight .50A. B. C. of Wireless Telegraphy, (Trevert) 1.00Wireless Telephone, (Cloth Bound), by H. Gernsback .50How to Become a Successful Electrician 1.00Model Flying Machines .50Books of Plans and Building Construction .50Aeroplane Portfolio .50Electric Wave Telegraphy, by Dr. J. A. Fleming 7.50Electrical Dictionary, Pocket Edition, Full Leather, Thumb Indexed .50

VALUABLE 25c. ELECTRICALHAND -BOOKS.

Size 5 ins. x 7 ins. Sent Postpaid.WIRELESS

100 How to Make Wireless Instruments. The best experimental book ever pub-lished. Can't be matched for $3.00. Written by Twenty Wireless Experts.Tells how to make 25 different pieces of apparatus. 76 illustrations. 96pages.

101 The Wireless Telephone. By H. Gernsbaek. The first wireless telephone bookfor the experimenter and amateur. Chock full of valuable information.Tells how to make battery wireless telephone outfits, to work over severalmiles at low cost. 60 illustrations. 64 pages.

102 Construction of Induction Coils and Transformers. Compiled and arranged byH. W. Secor. It has different chapters on the construction and design ofInduction Coils from 44 inch to 12 inch spark. Also chapters on HighTension Transformers, Testa Coils, Transformers, High Tension Condensers,Iron Core dimensions, Sparking distances, Wire values. 72 illustrations.100 pages.

103 Wireless Hook -Ups. The best book on wireless connecting diagrams inexistence. 182 different illustrations for every imaginable kind of an out-fit are shown. 96 pages.

ELECTRICAL104 Electricity. The Study of Its Laws for Beginners. N. H. Schneider.105 Dry Batteries. flow to Make and Use Them. N. H. Schneider.106 Electrical Circuits and Diagrams. Direct Current. N. H. Schneider.107 Electric Bells and Burglar Alarms. How to Install Them. N. H. Schneider.108 Modern Primary Batteries. Their Construction and Maintenance. N. H.

Schneider109 Experimenting with Induction Coils. Full of interesting experiments. H. S.

Norrie.110 Small Accumulators. How to Make Storage Batteries. P. Marshall.111 Simple Electrical Working Models, and How to Make Them. P. Marshall.112 Electric Batteries. How to Make and Use Them. P. Marshall.113 Telephones and Microphones. Flow to Make Them. P. Marshall.114 Small Electrical Measuring Instruments. How to Construct and Use Them.115 Electric Lighting for Amateurs. P. Marshall.116 Small Dynamos and Motors. How to Make and Use Them. F. E. Powell.1.17 Static Electricity. Interesting Experiments for Everybody. P. G. Bull.118 Practical Electrics. A Universal handbook on everyday electrical matters.119 The Wimshurst Machine. How to Make and Use It. A. W. Marshall.120 Alternating Currents. Simply explained in ordinary language.121 Inventions. How to Protect, Sell and Buy Them. With the necessary forma

and how to fill them out. By F. B. Wright. This book is especially writ-ten for inventors and those who are Inexperienced.

THE ELECTRO IMPORTING CO.236 FULTON ST., NEW YORK CITY


DO YOU KNOW ? ?The New Wireless Law of August 13, 1913?How to Receive Wireless Messages?What Distance You Can Practically Telephone Per Wireless

Phone?The Wave Lengths of the Wireless Stations at Glace Bay,

Arlington, Etc.?How to Erect a Wireless Aerial?How to Receive Time by Wireless?How to Photograph Electrical Discharges?How to Experiment with Spark Coils?How to Test Storage Batteries?How to Make Tesla's Experiments?How to Calculate Radio Wave Lengths?What is Ohm's Law?What Resistance Have Different Metals?What Is the Capacity of a Condenser?What are the Dimensions of an L Aerial?How Far Does a Spark Coil Send?What Size Wire Receivers are Wound With?How You Can Charge a Storage Battery with A. C. Current?How You Can Produce a 3 -Inch Spark Without Batteries or

Coils or Current?How You Can Solder Aluminum?What Is a Joule?How Many Grammes are in a Drachme?

Thousand other questions are answered in our

ELECTRICALCYCLOPEDIA

Write today for your copy, using cou-pon below

236 Fulton Street,New York City.

I enclose herewith 10 cents instamps or coin for which pleasesend me your Miniature Wireless De-tector and your Electric Cyclopedia for1914, No. 14, 2nd edition, containing400 illustrations and over 1600 articles andvaluable information on Electricity and Wireless.Book also contains 20 free coupons for your 160page wireless course in twenty lessons.

ELECTRO Tearoff here andmailIMPORTING to our address. Iff

COMPANY, you wish our Cy-clopedia only

send 3 centsinstead of\ 10 cents.

Name

Address

State

Big Price ReductionThe Greatest Offer Ever

Made by UsAs is well known, we formerly did an extensive export business

with Europe, but on account of the war and the restrained ship-ping caused thereby, we are forced to sell a large quantity ofgoods which were to be shipped to Europe, in this country.

Most of our large European orders having been cancelled, weare offering our choicest instruments at prices from 33 per cent.to 15 per cent. lower than our already low catalog prices.

These articles are identical with the ones we have sold foryears at the higher prices, and bear our regular guarantee. Weguarantee full satisfaction on all goods.

Never in the 10 years' history of our business have we beenforced to sell goods at such unheard of prices, and it is herewhere YOU BENEFIT.

Look at the prices below and see what you will save. Youwill marvel how we can afford to do it.

FormerPrice

Cat. Page 15, No. 9300 Radloson $4.50" 18, No. 9255 Rotary Potentiometer 2.00

19, No. 9500 Commercial Detector 3.7520, No. 9700 Galena Detector 1.25

" 22, No. 8070 Phones 4.50" 23, No. 1305 Phones 6.35

24, No. 6666 Phones 7.75" 26, No. 3500 Condenser 4.00

27, No. 8486 Tuner 3.5028, No. 12002 Loose Coupler 4.0030, No. 8487 Loading Coil 2.5034, No. 8271 Sending Helix 6.00

Oscillation Trans-former 10.00

Lightning Switch, 250volt 2.25

Lightning Switch, 600volt 3.00

Transcontinental Out-fit 24.00

69, No. 1251 R. E. Storage Batteries 2.0069, No. 1252 H.O. Storage Batteries 1.2570, No. 555 Electro Storage Bat-

teries, 6 volt 60 A. H. 8.00No. 7199 Revolver Flashlight 1.50No. 12500 Rectifier 5.00No. 7000 Tesla Transformer 5.50No. 9000 Static Machine 4.50

di

44

di

id

34, No. 9600

41, No. 1616

41, No. 1617

56, No. 1600

75,94,96,

102,

NOW $4.001.753.001.004.006.007.253.503.253.502.255.00

7.50

2.00

2.75

22.151.751.00

7.501.254.254.003.75

Our terms on these special reduced prices are cash with order.No C. O. D. shipments sent. Now is the chance to buy! Wire-less Course allowed with these goods as explained on page 128

of catalog.

This very exceptional offer is made only for a verylimited period. No orders at these special prices will beaccepted after December 25th.

The Electro Importing Co.Manufacturers

236 Fulton Street New YorkFree Wireless Correspondence Course in Twenty

Lessons by S. Gernsback, A. Lescarboura, and H.W. Secor, E. & R. Eng., with every order. Seecatalog for information. WAR

In Europedon't affect our largestocks. We ship within24 hours as in the past.95 per cent of ourgoods are made in ourfactories in the UnitedStates.


FLWATRPPAML EXPERIMENTER.

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