a

Su JPPLE} LER MEN’ Ne: 142 7

eT anes ies —————

st (ftice « ew York, N. as Second ( jase Matte r Copyright, 10% y Munn & Co, scientific American, established 1845 y alanine , >L” r > 4 oT Scientific Ame . le $5 a year ; ( , O O28 Sci rican Supplement, $5 a year. scientific American Supplement, Vol. LV. No. 1428 J NEW ) Kt kK, M A . 16, 1905. { Scientific American and Supplement, $7 a year

CASTING IN THE GREAT FOUNDRY,

ROLLING A HEAVY ARMOR PLATE. THE KRUPP WORKS AT ESSEN.—IL

9287

(Concinded from SupeLewent No, 1427, page 22862, }

THE KRUPP WORKS AT ESSEN.—IL.*

By Day ALLEN WILLEY

Born Friedrich and his son, Alfred Krupp, believed hat a successful industry should own not only the facilitie for production yut the ources of raw ma- terial forming the base ind this is wh he coal and re mine in connection with the blast furnaces form uch a notable adjunct of the enterprises under consid ration (one of he principal oal mines ocated practically on the ite of the Essen works he othe vo being ituated near Bochum in all hey ym prise even working pi of which three are at Essen The former have a maximum depth of 1,700 feet, and it present no le han en ein of coal are ene vorked on two level Line eins varying trom to i Leet n thickmne Most of he oal ecured by hand mining yt ie works are quipped with both

overground and underground draining machiner i

hvydraulle ir compre or for operating ventilators while a separating and washing floor ; installed which has a capacity of 100 tons hourly Che worl ings near Bochum contain thirty eins with a tota thickness of 112 feet They are much more extensive than the pits at Essen, and irnish most of the total output of the Krupp mines vhich represent near! 1.500.000 tons yearly They are ilso provided with overground and underground draining machinery, a well as hydraulic air ompressot vhich have a ca pacity of 10,000 ecubie feet hourly, in addition to four ventilators and four eparation plants, treating 00

connection with the mines are sets total daily output of 700 tons mut

hour In of coke having a These are of the vertical type vith apparatus for

tons an vens

erved from above

are not provided securing by-pro

ducts, such as is installed in most of the modern ovens of the United States rhe irious groups of iron-ore deposits produce annually about 520,000 tons They include, as stated, 667 different allotment producing hematite and red ore as well as manganese rhe

inder the

and a ine

Krupp interest in the Spanish held title of the Oreonera [tron Ore Company ]

of steamships owned by the Krupps is devoted to

mines 1s

its transportation to Germany The blast furnace capacity not as large as might

be imagined when contrasted with the capacity of the

SINGLE

other, works. The principal plant, the Rheinhausen, 8 comparatively new, being built in 1896 It ineludes three furnaces of 14,150 cubic. feet capacity each, pro- lucing from .200 to 225 tons every 24 hours. The furnaces are provided with steam hoists, four Cowper heaters, and produce principally Bessemer and hema tite pig iron An interesting feature in connection with the plant is the service of le ore, a series of Brown hoist conveyors electrically driven being used for transferring the ore from shipboard to the plant

The blowing engines are of the vertical compound

type, furnishing 32,000 cubie feet of air per minute but the power plant also includes a gas.engine fed by furnace gas which operates an electric motor, two 250 horse power steam engines for operating ynamos and two compound pumping engines. The other fur

aily, which livision of the Krupp furnaces at Mulhofen

naces produce the balance of the 1,900 tons « is the average output of

industries They

this

include foul

works, three at Hermanns works, and four at Johan nes works, but none are of modern type The Germania shipyard, or the Kiel, plant as it is

called, after the

located is one of the

name of .the city oldest in

neat Europe

sometimes which it is

Originally a specialty was made of marine engines and boilers. The present works were located at Gaar den, a suburb of Kiel, in 1865, and were leased by the

Krupps in 1896, and only purchased last year. Fried

rich Krupp realized their value as an adjunct to his other industries, and since they have been under the present control, they have produced marine architect ure, not only in battleships, cruisers, and smaller

While the plant Kiel Harbor of

war vessels, but merchant vessels

at present in use has a frontage on

about 1,300 feet and covers 350 acres of ground, an viditional area has been purchased, which is more than double its present capacity As it is, slips are provided for the construction of seven vessels at one

the slips ranging in length from 377 to 640 feet width of from 8&5 to 100 feet. Three others which are planned will range from 600 to 836 feet each, but as will be noted from the dimensions, the facilities are such that, the largest type of battleship vet planned can be built in the most capacious of these

time with a

inclosures, They represent the latest idea in con- struction, the lower portion being of concrete with

* Specially prepaved for the ScLENTLFIC AMERICAN SUPPLEMENT.

SCIENTIFIC AMERICAN SUPPLEMENT, No. 1428.

ire closed by pontoons Four sides, but are suffi- overhead traveling that the ma-

side walls of granite, and are inclosed with lofty to allow the use of operated by motors, so transferred in this manner without de- extensive is so arranged that a ordinary

glass roofs and ciently cranes terial can be lay One of the most flotilla of four or five boats of the size can be constructed at desired The mechanical equipment is on a par with the Essen works in design and capacity rhe various de

electric

torpe do

once if

partments, such as the forging, fitting, and bending hops he plate yards, mold loft, joiner and paint hops, are provided with a complete outfit of steam ind lectrically-driven machinery Other notable di

also for the boilers, a marine

making water-tube

model and plant for

plant for eylindrical plant, and a

visions are a manufacture of

opper-torging testing

boilers and engines The equipment includes about 1.000 machine tools in addition to 10 steam hammers ind 7 ivdraulic and electric cranes The electric power is distributed by a ries of 260 dynamos and motor It is at the Germania yard that the cele

installed for weights on

placing battle

brated 150-ton crane has been ordnance, engines, and other heavy

ships and merchantmen

Reference has already been made to the importance of this plant in the construction of war vessels. Among the notable raft completed are four battleships for he German navy, including the Worth of 10,000 tons, the Zihringen of 11,800 tons, and another ship recently placed in commission of 15,000 tons \ number of the principal naval vessels, such as the battleship Jaden have been rebuilt Recent addi tions to the fleet of German cruisers, such as the Prinzess Wilhelm Nymphe,” and \mazone were

constructed in these lips One of the most notable

pieces of work was the Askold,”” for which the com- pany secured the contract from the Russian govern ment in competition with several other German firms is well as Italian and Russian yards This cruise

which is of 6,000 tons, was not only built for speed, but to carry unusually powerful batteries She pre- sent 1 peculiar appearance from the fact that she

arries five funnels After being completed she at-

tained a speed of no less than 24 knots an hour with her triple screws, one knot more than the required rate, developing 19.999 horse power Among the ad litions to Germany's merchantmen built at the Ger

May 16, 1908,

posite vessels, and in the under-weter fittings of ir

and steel ships

3. The decay of the brazing-metal in copper stear

pipes +. The deterioration, as distinguished from oxida tion, of cast iron used for parts of marine engin«

appliances which were in freque1 or continuous contact with sea-water.

>. The decay of propellers made of the paten when fitted to copper-bottomed vessels. In the case of was apparent tha metal became eaten away into holes, whil mentioned the metal appeared t former action is “cor

ind also for other

some bronzes condenser-tubes it ome of the in the ther cases retain its original form. The rosion,’ and the latter “decay.

Chemical analysis of the that a shange had occurred in the metal, but did not explain why its so completely modified It showed that in alloys the process had been mainly one of dezinckification, or loss of zine hile in cast iron, part of the iron, and also of the manganese had disappeared, the whole of the graphitic carbon re- maining

portions showed composition of the strength and prop

decaved

erties were

copper ine

possibly

Although the decay of copper-zinc alloys had been known for many years, the first published researc! into its cause appears to have been made by Prot

case of the fail steam-pipe He pointed o pipe, when microsco)i was seen to possess a duplex structure Muntz metal, both constituents bein definite chemical compounds of copper and zinc, but one richer in copper than the other; and he attributed the decay to local galvanic action set up between these constituents, whereby in the first stage, the one less rich in copper becomes dezinckified, and hat richer in copper also lost its zinc, the whole becoming a spongy mass of copper

Microscopic study showed that the Muntz metal tube plates, had been subject to similar decay to that pointed out by Prof. Arnold, and also that in the decay of cast iron the complexity of structure doubtless led to the same result, the decay in this case advancing along the lines of the graphite plates and leaving th: phosphide eutectic portions till the last

This explanation of local galvanic action,

Arnold, who in 1898, investigated the ure of a marine boiler that the brazing-metal of the ally examined,

similar to that of

subsequently then

rods, et«

however,

SHEET OF METAL ROLLED AT THE ESSEN

mania yard are the Lloyd ships “Bonn” and “Halle also the famous “Kaiser Wilhelm der Grosse,” which has made such a record in trans-Atlantic service.

The enlargement of this yard, carried out as planned by the late Friedrich Alfred Krupp, will make it prob- ably the greatest shipbuilding plant in the world, and give it facilities for turning out more than twice the tonnage which its former capacity represented, as a considerable portion of the present works will be rebuilt It irea of 600 acres, and em

about 3,000 men than the old yard, when shops are in operation Most of the have been completed features in connection with the described are the proving grounds for ord- nance at Meppen, laid out in connection with the Essen works, also the Gruson works It is here that the tests have been made which have given the Krupp reputation among military experts, owing trials, which have not only projectiles and armor plate manufactured: to attacked

will cover an ploy all of the new improvements interesting

more

lwo industries

such a elaborate and costly included ordnance, but Sections of every kind of armor plate grounds and

£uns

to the

fill orders are carried to these

by ordnance of varied caliber. Every piece of artil- lery is alsg-tested at one of the proving grounds be- fore being sent away from the works

THE DECAY OF METALS.*

By J. T. Miron, M and W. J. LARKE.

Inst. C. E

Tue durability of metals under the conditions in which they were actually is of great importance, and must always receive as careful consideration from engineers as questions of strength or cheapness. Cop- per, brass, gun-metal, and other alloys were chosen for use on account of their durability but even these metals were sometimes found to corrode or decay under seemingly obscure conditions. It was to cases of such decay, and to a discussion on their probable causes that this paper is devoted

The following examples of the decay referred to are adduced

1. The densers.

2. The decay of bras¢ or yellow-metal bolts in com-

used

pittine of the tubes of marine surface-con-

* Abstract of a paper presented before Institution of Civil Engineers,

WORKS.

account for the corrosion and decay of con having iron

did not denser-tubes which were made of an alloy not a duplex structure; nor did it expiain why cast in some cases did not decay, even although its composi tion and structure were the same as in other where decay took place

Condenser-tubes were usually sisting of, nominally, 70 per ent zine. The Admiralty spe« than 70 per cent and 1 per cent tin, the re mainder being of zine while one of the large mai! steamship companies, as the result of considerable ex perience, had the tubes made of 78 per cent copper, 21 per cent zinc, and | per cent tin.

‘These were nominal compositions, for commercial copper and zine were rarely pure If the impurities became uniformly diffused through the mass of tl! alloy it would still be homogeneous, but if they ha

cases

an alloy con cent and 30 per

ification was, not les

made of copper

copper

a tendency to segregate, as it was well known som: elements did in steel, there would still be such wan

of uniformity as might set up local galvanic action ar lead to local pitting or corrosion. Segregation wa not only possible during the solidification-of the. all in the original casting, but might also occur while tl metal was at a high temperature during the operatio: of annealing, which was several times repeated*in t! course of the drawing process

If segregation occurred during solidification only, t! drawing process would cause the impure portions<to

much elongated in the direction of the tube’s lengt and the resulting corrosion would be seamy;° where

if it occurred also to a marked degree during anne: ing, the corrosion would affect more rounded area Examination of the insides of condenser-tubes reveal cases of deen corrosion of both kinds; but in additi: it was seen that the general surface of the inside the tubes had become partially dezinckified to an ext«

sufficient to cause it to crack when the tube is+ fl tened. In order to determine whether the various impu!

ties which are commonly present in copper-zine alto do tend to segregate or diffuse during annealing«sor experiments, detailed in an appendix, were~mat These experiments incidentally threw some light up: the changes of structure which Muntz metal, and al the 70 to 30 copper-zine alloy underwent, due changes of heat treatment.

Considerable protection is given to copper-zinc alloy

l

l

I

May 16, 1908.

hen exposed to the action of sea water, by the prac- e, adopted by the Admiralty, of requiring the addi- n of at least 1 per cent of tin to all such alloys. rhe conclusions arrived at were: lron.—Beyond the very small portion which ibtless existed in a state of solid solution in the ss, iron occurred in combination with zinc as all isolated particles, which were neither diffusible r liable to segregation. These particles were prob- ly a zine-iron alloy. Lead 4 small portion of this metal would also ist in brass in a state of solid solution; but beyond saturation point, lead did not diffuse into brass. mall proportion, however, in solid solution, mater- lly increased the liability to corrosion. Tin.—This metal could exist in small proportions olid solution in brass and in Muntz metal. In the tter it probably entered into both micro-constituents; t when present it certainly occurred in the one hich was richest in zine, as was shown by the otective effect it gave to this constituent against rrosion in sea-water. In larger quantities, tin would o diffuse into brass, the extent of the diffusion de- ending upon the temperature to which it was raised. t+. Zine.—Zine alloyed with copper in all proportions, nd if it was not uniformly distributed through the etal, it tended to become so by prolonged heating. Some experiments were also made to determine the ilvanie action between copper, iron, brass, Muntz tal, ete. when in contact with sea-water; and ther experiments showed that weak applied currents, hen long continued, had a decided corrosive action on copper and its alloys when immersed in sea- ater, the amount of corrosion—with the same cur- nt—being greatest in those containing the highest

roportion of copper. With a current of 0.001 ampere acting on an im- ersed area of 40 square centimeters in the case of

luntz metal, the wasting produced was confined to

e dezinckification of the constituent poorest in cop- er; but the same current, acting upon 60 square cen- meters of ordinary brass condenser-tubes, gave rise a fairly uniform corrosion, both the copper and the inc of the alloy being dissolved.

Summarizing the results of the investigation it ould appear that—

|. Decay was more frequent in metals which had a iplex or more complex structure than in those which

yere comparatively homogeneous.

Decay was due to a slower or less energetic action an that causing corrosion, and, moreover, it re-

ired an action which removed part only of the con

tituents of the metal, whereas corrosion removed all

he

hemical

material attacked.

Both decay and corrosion might result from action alone, or from chemical ana elec- olytie action combined.

{. Pitting, or intense local corrosion, was probably ften due to local segregation of impurities of the etal, but it might also in some cases be due to local regularities of surface or structure producing local

rregularities in the distribution of galvanic currents.

In the case of brass exposed to sea-water, tin as distinctly preservative, while lead and iron were

h injurious, rendering the brass more readily cor-

vlible The percentage of the latter elements should, herefore, be kept as low as possible in the case of all etal intended for purposes where contact with sea-

he internal surfaces

he drawing

ater was inevitable

6. With a view to obtain a minimum of corrosion, of condenser-tubes should be as mooth and uniform as possible; and in order to sure this, the cast pipe from which they were rawn should be smoothly bored inside, either before was commenced, or in an early stage of process, as was done in the manufacture of brass ler-tubes.,

i. The experiments with an applied current show

hat electrolytic action alone, even where exceedingly

heir

inute currents were in question, might result in very

ere corrosion or decay. Every effort, therefore, hould be made to prevent such action, by careful in- ation of all electric cables. Where galvanic action is inevitable through the proximity of different etals exposed to the same electrolyte, the currents

resulting should be neutralized by the application of

plates in the circuit, so arranged that they would negative to both of the other metals.

ON THE “EMANATION SUBSTANCE” FROM PITCHBLENDE, AND ON RADIUM.* By F. GIreset.

radio-activity of the compounds of thorium and characteristic emanation has been very ther- ughly investigated by Rutherford (cf. E. Rutherford

Tre

ind Soddy, Zeit. fiir Physikal. Chem., 1902, xlii., 81).

His endeavors to prove that the relatively very insig-

ficant activity of thorium is due to the presence in small quantity of a strongly active substance were successful. It is true that Rutherford, by extrac- n of thorium hydroxide with water, or by precipita- n of thorium salts with ammonia, obtained, after iporation or expulsion of the ammonia respectively, ill residues almost free from thorium, which were nsiderably more active than the thorium used, but properties of these residues were altered. While thorium by such treatment had lost a part of its ivity, after some time it regained its original activ- but, on the contrary, the extracted substance, which therford called “ThX,” gradually decreased in act- ty up to the amount of the thorium present.+ fence Rutherford concluded that the thorium itself st be the primarily active substance, and that “ThX” formed from it continually by rearrangement of the

ms Now, I have obtained a body from pitchblende Rerichte, 1902, xxxv., 3610), which, first, possesses t considerably higher degree the same kind of ac- ty as thorium, and secondly, unlike “ThX,” has not

terichte, 1902, xxxv., 3608. "he only temporarily active rare earths previously separated by me richte, 1900, xxxiii.. 3670, : 1901. xxxiv.. 3776) from uraniam mineral, as 18 from commercial uranium salts (Berichte, 1900, xxxiii., 1665) be- ved in the same way as ThX.

SCIENTIFIC AMERICAN SUPPLEMENT, No. 1428,

diminished at all in linear radiation and emanation in about six months. But as the physical properties agree in other respects, and as it also appears to be related to thorium (and the rare earths), from these two new facts mentioned above we are led to adopt a different view from Rutherford’s concerning the origin of the activity of thorium.

The emanation substance of pitchblende belongs to the group of cerium earths, or at any rate reacts in the same way. I have already shown (Berichte, 1902, XXXV., 3611) that the rare earths obtainable from pitch- blende possess a constant activity. | was not then able to observe an emanation* because this, as has already been shown, does not belong equally to all compounds, but is dependent upon chemical conditions.

The method of preparation of the raw material for the emanation substance is the same as that employed for the separation of the rare earths, and is best ef fected by means of potassium sulphate, after removal of the heavy metals. Hydrogen peroxide gives with the solution of the potassium double salt a fairly active precipitate, displaying the emanation. The precipitate with oxalic acid, which also contains the emanation substance, and in consequence of the large amount of didymium contained in it is colored faintly pink, yields no emanation But a thoroughly rested eye may also perceive the activity of this last precipitate on the luminous screen.

The preparation of this material, which is to be ob- tained in great quantity, must be deferred to a future period. For the present research the mother-liquor freed from radium bromide, and the greater quantity of barium bromide, sufficed; this has already been rendered richer in the emanation substance, i. e., it contains it least adulterated with inactive earths. The treatment of this consisted in dissolving in hydro- chloric acid the precipitate obtained with ammonia, after removal of any barium precipitated with it by means of sulphuric acid, and evaporating to dryness on the water-bath. On taking up the residue after evap oration with water, several centigrammes of an insolu ble residue remained behind, which yielded the most strongly active ‘emanation) substance yet obtained This residue was not investigated but reserved for the physical experiments.

The filtrate gave with sulphureted hydrogen only a small active precipitate which contained lead. The precipitate obtained afterward with oxalic acid amount- ed to about 2 grammes after further purification, and was almost as inactive as the insoluble residue. The precipitate formed by adding ammonia to the filtrate, and the final precipitate consisting of magnesia formed on addition of ammonium carbonate, were less active. Also the small remaining residue left on driving off the fumes from the last filtrate after evaporation was very active

All precipitates, with the exception of those formed by oxalic acid and sulphureted hydrogen, showed emanation which generally increased in the first few days. The ammonia precipitate, as well as the mag nesia precipitate, contained small impurities of rare earths, after separation of which the activity corres- pondingly diminished, and grew stronger in the latter.

The oxalate of these earths becomes almost white on ignition, with a very faint salmon tint, and is then easily soluble in hydrochloric acid, The solution is at first orange, and becomes colorless with evolution of chlorine; similarly the solution in nitric acid on ad- dition of hydrogen peroxide, but only very little ceri um is obtained as hydroxide by the hydrogen peroxide reaction. The concentrated solutions of the salts show no trace of an absorption spectrum, and thus are practically free fron. didymium. Potassium sulph ate, as well as hydrogen peroxide, completely precipi tates the solution of the potassium double salt, which last gives also an emanation. Thiosulphate gives no precipitate on boiling, only a very slight turbidity. Ammonium oxalate does not extract from the oxalate sufficient thorium to be precipitated by ammonia. After driving off the ammonium salt a trace remains, which, however, is not more active than the undissolved oxa- late. But it is noteworthy that the oxalate thus treat- ed then gives the emanation very strongly.

Like the lanthanum salt the chloride crystallizes easily, is itself phosphorescent after removal of water, and shows the emanation. In the Bunsen flame only the sodium line is visible spectroscopically. The sul phate forms definite crystals, and has no emanation or phosphorescence. According to these reactions thorium cannot be present to any material extent, and the traces present cannot be the cause of the activity. Lanthanum appears to be the essential impurity. It may be mentioned that the percentage amount of this earth present in a new radio-active element must be about 0.1 per cent, if it be assumed that the Becquerel radiation possesses the same intensity and the same power of penetration as in the case of radium. The Becquerel radiation of the preparation thus affects the barium platinum cyanide screen in the same degree as a barium carbonate with about 0.1 per cent radium For a smaller intensity and power of penetration of the linear radiation than in the case of radium the per- centage content would of course be higher. Thus in the case in question about 2 grammes must contain at least 2 milligrammes of the element. From what has already been stated, this can be neither radium nor polonium For the present I will not follow the cus- tom, usually adopted from practical considerations, of giving a name to the hypothetical element, until it has been established how Debierne’s substance (actinium), hitherto known only as thorium, also behaves as re- gards the emanation.

In the examination of the physical properties of the emanation substance the following results have been obtained:

The linear Becquerel radiation is. capable of being deflected, at any rate partly, by a magnet. No decrease in it could be observed in about six months, but rather

as far as my observations go to show—an increase, similar to that in the case of radium. The degree ot power of emanation of different preparations in the same chemical compound is proportional to the in- tensity of their Becquerel radiation. Igniting for a

* In all researches I have paid attention only to the emanation when it can be observed on the zine eulphide screen, + Commercial thorium preparations do not affect the luminous ecre*™

short time does not destroy the power of emanation.

Glass vessels in which the substance is kept phos- phoresce, and on opening them the smell of ozone is perceptible.

The strong and rapid inducing effect of the substance is very striking. Most objects, e. g¢., paper, which are shut up in the same receptacle (as small as pos- sible) with the substance, very soon exhibit the same characteristics as the substance itself. If the prepara- tion wrapped in paper is held at the back of the plat- inum cyanide screen for half to one minute the spot in question becomes luminous for a short time. No luminosity appears on laying on the varnished side of the screen.* This induction was clearly produced, not by the Becquerel radiation of the preparation, but by the emanation; it can be regarded as an absorption of the emanation, and is thus more easily perceived in porous substances, such as paper. The moisture present in the substance plays an important part in it Wet filter-paper is made more strongly and last- ingly active than dry. Impregnation with aqueous ammonia or hydrochloric acid gives the same result as with water

By means of a current of air the emanation can be extended, so that the usual screens if they are un- varnished or prepared with gelatin (which absorbs the fumes) are rendered luminous by it. The phos- phorescing zine sulphide is best adapted for this pur- pose. The current of air momentarily discharges an electroscope. A thin film of celluloid intercepts the emanation,

If the preparation is laid in a cylindrical metallic capsule, closed at one end, and this is held vertically with the opening downward toward a zine sulphide screen negatively charged by an influence machine at a distance of from 5 to 10 centimeters from it, a diminished phosphorescence image of the opening of the capsule appears on the screen. This is brighter at the edge than in the middle By inclining the screen, an elliptical instead of a circular surface is projected A square opening gives an image in the form of a square with each of the sides slightly depressed in the center.

If the opening of the capsule is diminished to any desired form, e. g., by means of shaped shutters, very sharp, still more clearly and homogeneously luminous diminished images of the openings are obtained. The phosphorescent image so affects the screen that it be- comes luminous for a long time, and gives secondary emanation. If the capsule is insulated, the image be- comes fainter. A current of air, which only extends the secondary emanation, no longer influences the po- sition of the image. Direct convergence of the “beam

‘of rays” could not be established; only a grouping to-

gether apparently takes place; generally the image is smaller for greater distances between screen and cap- sule. If the image is approached by a conductor con- nected to earth, in consequence of the positive charge induced by the negative screen, repellence takes place. The image is deformed to a straight or semi-circular line, according to the shape of the conductor; the space between it and the conductor amounts to 1 to 2 centimeters. <A dielectric rod held between the screen and capsule does not repel so energetically, and only casts an enlarged shadow. If a wire net connected to earth (which interrupts the electric field) is held in the place of the rod, the screen remains dark; on insu- lating the wire net the emanation penetrates.

All the phenomena are the same if the screen is negatively charged and the capsule connected to earth, or if, conversely, the capsule is positively charged and the screen connected to earth

From these experiments it follows that the emana- tion experiences in the electric field an acceleration in direction from the positive to the negative electrode. The emanation changes into a radiation; it must itself possess a positive charge.

Up to the present, with the means at my disposal, I have not been able to perceive any effect caused by a magnet in the emanation, which is influenced by the electric field.

The question whether the emanation is to be garded as the positive ions, and the new radiation as a parallel to the channel radiation, or S, radiation of E Goldstein (Verh. d. Dtsch. Phys. Ges., 1902, iv., 228), or whether the emanation is simply the vapor of the substance itself, which, according to Curie’s researches on radium, can itself assume a positive charge, may be left undecided. In any case, the emanation of my substance is very different from that of radium, which does not cause the phenomena described. | should suggest calling the new rays “E rays.”

The measurement of the flame spectrum of radium Prof. Runge has most kindly undertaken. He will re- port on it in Drude’s Annalen, 1903, ii., 1.

According to Profs. Runge and Bodlander, the gas constantly evolved from solutions of radium bromide is essentially hydrogen

The following communication comes from Prof. Bod- lander:

“The solution of 1 gramme of the 5 per cent radium preparation sent to me gave off 3.5 cubic centimeters of gas in sixteen days. Seventy-eight per cent of this gas was hydrogen, and 17 per cent oxygen, while the solution became colored brown by bromine. Thus a sort of electrolysist occurs under the influence of the radium, in that the negative electrons change the hydrogen ions into nevtral molecules, while by the positive electrons, bromine or hydroxy! ions are dis- charged. The experiments on the duration of the evo- lution of gas under different conditions will be con- tinued, so that the source of the not ineonsiderable energy (1.8 watt-seconds 0.43 cal 18,000 2. e.m. daily) obtained from about 5 centigrammes of ra- dium bromide may be _ explained.”—Berichte der

Deutsch. Chem, Ges.

re-

* Only a pure radium ealt with the highest activity produces a bnef lomi- nosity of the platinum cyanide, but it is immaterial which side of the screen ix exposed to the radium,

+ Two Geisler tubes which I bad previously filed with radium gas (one with gas from solution and the other with gas from crystals) showed the hydrogen lines as plainly us possible, I did not then mention this, because it was not certain that the gas was absolutely free from water,

t Author's note.—The behavier of radiom eolutions discovered by me (Ann, d. Phys, a. Chem., 189%, Ixix.. 9%) with regard to the radia- tion, as opnosed to that of the slid salt. may be thus explained, The energy of the radiation is mavifested in the solution more in the form of a decomposition of the \. atez, a! !ess as Becquerel radiation,

22880

THE SERPOLLET STEAM AUTOMOBILE.* I, ARRANGEMENT OF PARTS ON THE CHASSIS

Tus article forms the first of a series descriptive of a steam automobile run by superheated steam

SCIENTIFIC AMERICAN SUPPLEMENT, No.

The construction of the throttle can be seen by

referring to the diagram, Fig. 4 It consists of z round cast iron box in two parts, viz., a flat bottom part, B, in which is a circular groove, i, and a cover, Ff’, on which is a rim, /, that fits in this groove when

SISA

Pia. 1.—THE SERPOLLET 12 H. P. SURREY.

generated in a so-called “flash” boiler. The entire ma- chine, as well as the system of steam generation em ployed, is the invention of M. Leon Serpollet, who is the original inventor of the boiler in question, an adaptation of which has been so successfully used on the White steam carriage in this country M. Ser pollet has thrice won the Rothschild cup, presented to the automobilist who covered a kilometer in the fast est time from a flying start His time this spring in the trials at Nice on April 4 was 29.19 seconds. A picture of his steam racer is shown herewith.

The 12 horse power surrey, or double phaeton, shown in Fig. 1, is a typical Serpollet car. The boiler and burner are situated beneath and back of the rear seat, the engine being under the center of the body, and driving the rear axle by a chain The pian view of the chassis (Fig. 2) will give the reader a good idea of the general layout of the machine and the arrange- ment of its parts

A is the gasoline tank in which air pressure is set up by means of a hand pump for first starting the burner, B, or for feeding it when the vehicle is stand- ing When the car is running, the small automatic pump, p, regularly forces the proper quantity of fuel into the burner through the pipe, b. O is the auxiliary hand water pump This is connected to the water pipe, ce, which regularly supplies the generator with water pumped by the automatic pump, P, that draws its supply through the pipe, m When starting or climb- ing a hill, more water can be supplied by hand if necessary. UL shows the driving cams of the fuel and water pumps, by shifting which with the lever, A, the stroke of the pumps may be varied, and more or less fuel and water supplied to the burner and generator, as desired. FF is the oscillating arm moved by the cams and to which the pump plungers are connected. R is a spring for holding #& in contact with the cams, while k is the rod connecting the cam-shifting lever with the handle, L, on the steering post

The superheated steam from the generator, C, is conducted to the safety throttle, fF, from which it passes to the engine through pipes, / and A These pipes are all tightly jacketed with corrugated asbestos to prevent loss of heat from the steam. Oil is intro- duced into the cylinders through the nipple 4 of the cross 1, 2, 3, 4, the other three nipples of which are connected to the steam pipes as shown N is the oil reservoir, and S the connecting rod operating the ratchet feed device, Z The exhaust from the motor passes through the pipes Q Q’ to the condensers, the ends of the tubes of which are seen at J} Y isa cylinder for the storage of compressed air used in connection with the water storage cylinder, Y, for automatically introducing water into the boiler by simply opening a valve, when first getting up steam or when extra water is needed in climbing a hill A small pipe, 7, connects the two cylinders

The letter 7' in both illustrations refers to the cam- shifting lever of the motor for varying the cut-off of the valves, together with its various rod connections and operating handle on the steering post The hori- zontal motor employed is somewhat similar to a gaso- line motor It has four cylinders in opposite pairs, each cylinder having an inlet and exhaust valve oper- ated by cams A complete description of this motor will be given in a future issue

Fig. 3 shows the dashboard of the Serpollet car, with the four gages, etc Gage 1 indicates the air pressure in the gasoline tank, A; gage 2, that made by the automatic fuel pump; gage 3, the steam pres- sure; and gage 4, the pressure in the automatic feed- water cylinder (Y, Fig. 2) F is the brake pedal that applies the band brake H, Fig. 2, to the brake drums of the rear wheels. The other pedal, W, opens the throttle when depressed. The throttle is normally held closed by a spring. D is the valve that controls the flow of water into the generator from the pressure cylinder, Y, Fig. 2. QQ’ are the exhaust pipes leading into the condenser, C

* Article specially adapted for the ScrENTIFIC AMERICAN SUPPLEMENT from a description of the Serpollet automebile published in La Locomotion,

fF is laid upon B and clamped tightly to it by bolts passing through lugs e, g, h

The bottom part, B, of the throttle has a perfectly flat surface on its upper side, in which are two holes— a round one, a, and a heart-shaped one, c. These holes connect, the one with the entrance pipe, W, of the steam, and the other with the pipe, 7, through which it makes its exit. The steam enters through a, which is always open, and fills the box. If ¢ is open, the steam forms a head in the inner passage, which leads

1428. May 16, 1908.

steam upon it. The port, c, is given its peculiar shape in order that the steam shall be admitted gradually to the cylinders at first. The valve should be kept either wide open or else closed, as it is not advisable to run with it half open.

The central plug, f, in the cover can be removed once in a while and a little gasoline injected to keep the valve from sticking, though this is a thing that very rarely happens, and then never more than once, sometimes when the vehicle is new. If anything gets disarranged about the throttle, the best way to do is to take it apart by removing the three bolts that clamp it together.

By the arrangement adopted, the car may always be left standing with safety and with the assurance that it will not start itself or run away unless some- one meddles with and presses the throttle pedal.

(To be continued.)

(Concluded from SuppLEMENT No. 1427, page 22871.) REPORT ON A VISIT TO AMERICA,

By Lieut.-Col. H. A. Yorke, R. E., Chief Inspecting Officer of Railways.—Board of Trade, London.

TIIl.——-SURFACE LINES, SUBWAYS, AND ELEVATED RAILWAYS.

Surrace Lines.—I examined the surface lines and tramways in a great many cities, viz.. New York, Brooklyn, Washington, Boston, Pittsburg, Detroit, Buf- falo, Toronto, and Chicago, and was interested to find that grooved