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32

A New Test for Arsenic.

The PRESIDENT-I will remind the members at this stage that Mr. Cookson's paper will come on for discussion at another meeting; meantime I propose a very cordial vote of thanks to Mr. Cookson. The description which he has given is very interesting, and we are all much indebted to him for such an abie paper on this important question.

The motion on being seconded was carried unanimously.

NOTICES OF BOOKS.

Fourth Annual Report of the Commissioner of the Imperial
Mint, Osaka, Japan. Hiogo: Hiogo News Office.
THIS report contains nothing of special scientific interest.
It appears that the foreign staff of the Japanese mint now
consists of two persons only, the chemist, Mr. W. Gow-
land, F.C.S., and the engineer, M. R. Maclagan, M.I.M.E.,
all the other posts being now filled by natives.
sanitary condition of the Mint department does not seen
satisfactory; 411 cases of illness and 11 deaths out of a
total of 602 men in their best years are remarkable, espe-
cially as none of the deaths were due to accidents. How
much of this is due to the climate and how much to the

The

CHEMICAL NEWS,
January 17, 1879.

formulæ given below (in thesis 10) may be capable of still further simplification.

We give an abstract of the author's theses:1. All have arisen out of the so-called cosmic ether, the one primitive matter which fills infinite space.

2. This primitive matter, whose motions make themselves known by the phenomena of light, beat, electricity, and magnetism is not infinitely divisible.

3. The portion of the original matter, which after continued division resists all further comminution, is the primary atom.

4. All primary atoms have identical (regular) form and equally great mass (weight), and are amongst themselves perfectly congruent.

bodies, is formed of primary atoms lying beside of each

5. The cosmic ether, the initial state of all nascent

other without definite law.

6. In these primary atoms there inheres a power or tendency to combine with each other.

7. By these combinations of the primary atoms there arise molecules of new bodies different from the primary

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nature of the employment cannot be known, especially as i.e., primary atoms unite together either by twos and threes,

we can find no mention of the number of men in each department.

or by the third and fifth powers of two and three.

9. These six primary compounds form the basis of all known bodies, the molecules of the so-called elements

being formed by combinations of such primary compounds.
10. These combinations take place simply according to
the law of multiple proportions. If in series (1)—
21=2=a; 2 = 8A; 23 =32=a

313b; 327-B; 35=243=b the molecules of bodies considered as elements are formed as follows:a2b2=2x 2+ 2x 3= 10=H. a2b2=2×32+ 2x 3= 70=Li. a2b10=2×32+10x 3 = 94 = Be. a1b 4=1×32+ 4×27=140=N. 11. If the mass (weight) of the primary atom =1 the above numbers show not merely the number of original atoms in the compound molecules, but also their molecular weights.

The Magic Lantern Manual. By W. J. CHADBURN. With
100 Illustrations. London: Warne and Co., 1878.
POOR Artemus Ward used to call himself a "jokist," so
Mr. Chadburn takes liberties with Her Majesty's English
and calls himself a 66 Lanternist." Whether he will and in series (2)—
succeed in adding a new word to the dictionary or not we
cannot venture to prophesy, but in any case he has pre-
sented his brother "lanternists" with a capital little book
on the magic lantern. He first of all describes the
ordinary old fashioned oil lantern and its objectives, and
then proceeds to give us an account of the Sciopticon, an
American invention, which ranks half way between the
old fashioned instrument and the oxyhydrogen and electric
lanterns. The pyrohydrogen and magnesium lanterns
are also described, as well as all the accessory instru-
ments connected with them. Clear directions are also
given for the preparation of the slides, both by hand and
by photography, whether by the silver or carbon process.
The part, however, which will most interest our readers
is that on scientific projections. For exhibiting diagrams,
optical effects, the decomposition of water, crystallisation,
&c., Mr. Chadburn tells us that the Sciopticon will serve
every ordinary purpose for class demonstration. This is
a fact that is evidently but little known to science teachers,
who always look on lantern demonstration as involving
endless trouble and an enormous outlay. We cordially
recommend Mr. Chadburn's little book to all science
teachers and lecturers.

The Unity of Matter: A Hypothesis. (Die Einheit des
Stoffes Eine Hypothese). Von A. WALDNER.
Zürich Zürcher and Furren.

THE author of this little pamphlet tells us in his preface
that the hypothesis in question is the result of an arith-
metical examination of the relations existing between the
atomic weights of the so-called chemical elements. He
undertook this investigation in June last (1878), but did
not make his results public, as no facts were known to
prove that these elements were capable of further decom-
position. The recent researches of Mr. Norman Lockyer
and his experiments on the transformation of the metals
have induced him to publish his hypothesis, which they
seem to confirm. He considers it possible that the

&c.

12. The conditions under which the original atoms combine together, and under which, inversely, compounds are resolved into their original matter are hitherto unknown, and are probably of a nature scarcely to be realised by the temperatures and pressures at the command of our present science and technology."

On this proposed law criticism would be obviously premature. But we do not see on what principle the author selects the factors by which a, A, and a, and b, B, and b are respectively multiplied.

CORRESPONDENCE.

A NEW TEST FOR ARSENIC.

To the Editor of the Chemical News. SIR,-In the CHEMICAL NEWS, vol. xxxviii., p. 301, it appears that Mr. Otis Johnson claims the discovery that when potassium hydrate is allowed to act upon aluminium in the presence of arsenic and antimony, that AsH3 is evolved without the evolution of SbH3. The above reaction is not new, having been discovered by M. Filhol, professor at Toulouse, prior to July, 1876. Prof. Filhol proposed the following, viz., if hydrogen is allowed to act

on arsenic by means of zinc or aluminium and caustic potash, and not by Zn and dilute sulphuric acid, as has always been customary in the Marsh apparatus, AsH3 is readily evolved, but if tried with antimony compounds not the least trace of SbH3 is observable. It is thus possible in the case of a mixture of As and Sb to disengage all the As and leave the pure Sb behind. It is also worthy of notice that when hydrogen is evolved by action of Zn, or still better Al, on potassium hydrate, if phosphorus be present, the colour of the ignited gas will be a beautiful green. The least traces of phosphorus can in this way be detected.-I am, &c.,

Analytical Laboratory, Lowther Hill, Forest Hill, December 28, 1878.

WILLIAM JOHNSTONE.

Action of Trimethylamin on the Sulphide of Carbon.-A. Bleunard.-These two substances react upon each other with some violence, forming sulphocarbamate of trimethylamin.

Biedermann's Central-blatt. Heft 12.

On the Requirement and the Transformation of Not suitable for abstraction. Matter in Saccharomyces Mycoderma.-A. Schulz.

Salicylic Acid as a Disinfectant.-Prof. Feser.-The author, in a prolonged series of experiments, found salicylic acid of no value, either as a prophylactic or in the treatment of putrid infectious disease, carbuncle, &c.

Revolution in Tanning.-Prof. Knapp proposes the use of a basic ferric sulphate instead of oak-bark or other tanniferrous material. He adds to a boiling solution of

CHEMICAL NOTICES FROM FOREIGN copperas the quantity of nitric acid requisite for the per

SOURCES.

NOTE. All degrees of temperature are Centigrade, unless otherwis expressed.

Comptes Rendus Hebdomadaires des Séances, l'Académie de des Sciences. No. 26, December 23, 1878. Explosion of Deflagrating Matter.-M. Dupuy de Lome.--The author examines into the causes of an explosion by which a M. Zédé had been severely wounded. The latter was endeavouring to find a compound which without exploding should be entirely resolved at the lowest possible temperature into gases and vapours, and which should serve as a motive power. For this purpose he employed a mixture of gun-cotton and of nitrate of ammonia. After finding the most suitable proportions he was studying in how far the speed of combustion, very slow in the open air, might be modified under increased pressure. On one occasion, when setting fire to the mixture contained in his apparatus, there occurred a violent explosion, attended by a flash of light. The tube, which had been tested up to fifty atmospheres, was shattered to pieces, and the experimentalist was seriously wounded. It would appear that a slight decrease in the orifice through which the gases escaped had changed the nature of the process from deflagration to detonation.

Magnetic Rotation of the Plane of Polarisation of Light under the Influence of the Earth.-H. Becquerel. The author points out that the experiment described in M. Joubert's paper (Comptes Rendus, lxxxvii., p. 984), is a reproduction of one which he had described on p. 1075 of the preceding volume.

Novel Phenomenon of Static Electricity.-M. Duter. A continuation of the controversy between the author and M. Govi.

Preparation of the Cobalto-cyanide of Potassium and of some of its Derivatives.-A. Descamps.-On pouring a cold solution of cyanide of potassium into chloride of cobalt there is formed a reddish brown precipitate of cobaltous cyanide. Care must be taken not to pass the limit of decomposition. This precipitate is kept at o°, carefully washed in water, and then dissolved in a slight excess of cyanide of potassium at the same temperature. The liquid if diluted with alcohol deposits crystals of a deep amethyst blue. These are washed in alcohol to remove the excess of cyanide of potassium, and are then preserved in alcohol at 95°. This salt is unstable and soon turns red. If dissolved in a little water it gives a deep red solution, which yields several reactions. With acetate of lead it yields an orange-yellow precipitate of cobalto-cyanide of lead. With chloride of cobalt, absolutely free from nickel, it gives a deep green precipitate, the cobalto-cyanide of cobalt and potassium.

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oxidation of the iron, and after the reaction is over adds more copperas. The hides are suspended in the cold solution at a suitable degree of concentration, and are ready in from two to four days.

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A successful competitor at the late Paris Exhibition offers his bronze-medal as a contribution to the lottery, as it was awarded him without any examination of the quality of his exhibits.

A long list is given of the substances used--apparently in France-for "denaturating" common salt to be used for agricultural or technical purposes. Some of these

additions must greatly increase the price.

Melted gallium dissolves aluminium even below 15°, forming liquid or semi-liquid amalgams which oxidise very slightly on exposure to the air, but decomposed water powerfully, the gallium being liberated in the form of metallic globules.

Dr. Kayser, after examining pigments such as whitelead, zinc-white, chrome-yellow, &c., finds that in addition to the heavy-spar, the quantity of which is stated by the seller and is allowed for in the price, gypsum is likewise present.

Prof. Schwalbe contributes a judicious essay on chemical nomenclature. He considers it unwise to attempt the introduction of new names for long-known compounds, and thus to carry us further and further away from the desired goal,—a universally intelligible terminology.

Doubts are expressed whether the electric light can compete with coal-gas from a commercial point of view.

the fact that in the years from 1838 to 1847 no fewer than The dangerous character of lead-compounds is shown by 3142 patients suffering from lead-cholic were admitted into the hospitals of Paris, although there were at that time only two white- and red-lead works in the city. Of these cases 112 proved fatal.

Plicque estimates the total yearly production of artificial ultramarine at 10,000,000 kiloes.

Incrustation of Lead Pipes with Sulphide of Lead. -A hot concentrated solution of sulphide of sodium is

34

Chemical Notices from Foreign Sources.

allowed to flow through the pipes for ten to fifteen minutes. They then appear as if coated within with a grey glaze, and water afterwards passed through them remains free from lead.

According to Dingler's Polyt. Journal the skin of the sting-ray(Raia clavata) is now used in place of isinglass for the clarification of liquids, e.g., beer.

{CHEMICAL NEWS,

January 17, 1879.

Dibrom-metaxylol-sulphonic Acid.-O. Jacobsen and E. Weinberg.-The authors examine the soda-salt, the acid chloride, and the amid.

On Paraxylidin.-W. Schaumann.-Paraxylidin is an oily liquid lighter than water, colourless when recently prepared, but turning yellow on exposure to the air; abundantly soluble in hot water, and boiling at 220° to 221°. It forms with acids well-defined salts.

Action of Potassa upon Tetra-nitro-diphenyl-urea.

Berichte der Deutschen Chemischen Gesellschaft zu Berlin, S. M. Losanitch.-The result of the reaction is a green,

No. 13, 1879.

solid body of the composition C13H6N6O9K2.

On Lotura Bark.-O. Hesse.-The author has isolated from this bark three alkaloids, which he names loturin, colloturin, and loturidin, the properties and compounds of which he here describes.

Conversion of the Nitriles into Imides (Fourth memoir).-A. Pinner and F. Klein.-The authors here examine the action of hydrochloric acid and alcohol upon hydrocyanic acid, which gives rise to ammonium chloride, Certain Substitutes for Quinin.-O. Hesse.-The ethyl chloride, formic ether, diethyl-glyoxylic amide, and Australian tree Alstonia constricta was formerly supposed diethyl-glyoxylic ether. When the same compounds to contain quinin; recent observation has instead merely react upon cyanogen the result is a predominating quan-detected alstonin, a bitter principle not possessing basic tity of oximidic ether, and secondarily chlor-ethyl, formic ether, and urethan. The authors have also studied the properties. Ditain, a principle obtained from the bark of A. scholaris is also no alkaloid. Crossopteryx bark has action of hydrochloric acid and alcohol upon propionitrile. been stated to contain quinin, but in the author's opinion On Butyl-chloral-cyanhydrate.-A. Pinner and F. it is little better than bad fire-wood. Klein. The authors study the behaviour of this compound with ammonia, urea, acetyl-chloride, concentrated sulphuric acid, hydrochloric acid with alcohol, and other compounds. They attach particular interest to the action of ammonia upon trichloroxy-valerianic acid.

On Naphthyl-phospho- and Arsenio-Compounds. -W. Kelbe. An account of naphthyl-phosphorous acid, diethyl-naphthyl-phosphin, triethyl-naphthyl-phosphonium iodide, dinaphthyl-phosphinic, and naphthyl-arsinic acid.

Determinations of Specific Weights.-F. W. Clarke. -Not susceptible of useful abstraction.

Etherification of Primary Alcohols.-N. Menschutkin. The author points out and rectifies certain errors in his paper, Berichte, x., p. 1728.

Action of Nitrous Acid upon Non saturated Hydrocarbons.- Paul Tönnies. In this preliminary communication the author mentions that if a saturated solution of potassium nitrite is brought in contact with a solution of the above compounds in glacial acetic acid, substances are formed which appear as addition-products of N2O3.

Preparation of a Series of Magnetic Compounds of the General Formula RO,Fe2O3 or R"Fe204.-Karl

List.-The author has obtained and examined the ferrates of lime, magnesia, manganese, zinc, nickel, copper, and lead.

On Cinchonin and Cinchonidin.-Z. K. Skraup.-To the former of these the author ascribes the formula C19H22N2O, and considers that cinchonidin has exactly the same composition.

Remarks on the Previous Paper.-O. Hesse.-The author finds the amount of carbon in cinchonin decidedly higher than does Skraup.

Analysis of the Mineral Spring "Tenniger Bad " in Somvixer Tobel.-R. Meyer.-The water contains an unusual quantity of strontium.

Angelicic Acids of Different Origins.-W. v. Miller. -Frankland and Duppa's methyl-crotonic acid is distinct from Neubauer's angelicic acid. The author's is a new isomer, of the formula C5H8O2.

Preservation of Drinking Water.-Hugo Schiff.The author recommends salicylic acid for the preservation of drinking water and brine with 1 part per 1000 of purified carbon disulphide for the preservation of zoological specimens.

Oxidation of Metaxylol-sulphamids.-Oscar Jacobsen. A controversial paper with reference to the communication by Iles and Remsen (Berichte, xi., 1326).

Remarks on Mr. Rice's Memoir on the Cinchona Alkaloids.-O. Hesse. The salts of quinidin, which Rice takes to be conchinin, do not contain the latter base. Reduction of Aceto-phenon.-K. Buchka.—A preliminary reply to Engler's paper (Berichte, xi., p. 934). Adulteration of Wine.-F. v. Lepel. The author gives the spectroscopic reactions of a mixture of magenta and the juice of Beta vulgaris.

On Aurin.-R. S. Dale and C. Schorlemmer.-The authors explain the formation of aurin by the following equation:

3C6H6O+C2H2O4=C19H1403+CH2O2+2H20.

Determination of Nitric Acid as Ammonia.—E. A. Grete. The author, on heating pure saltpetre with xanthogenate and soda-lime, obtained almost exactly the whole of the nitrogen present in the state of ammonia.

MISCELLANEOUS.

Royal Institution of Great Britain.-The Managers have decided that the next A&tonian Prize shall be awarded

in 1879 to an Essay illustrative of the Wisdom and Beneficence of the Almighty; the subject being "The Structure and Functions of the Retina in all Classes of Animals, viewed in relation with the Theory of Evolution." The Prize is One Hundred Guineas, and will be awarded or withheld as the Managers shall think proper. Competitors for the Prize are requested to send their essays (with or without their names being affixed) to the Royal Institution, addressed to the Secretary, on or before October 1, 1879. The adjudication will be made by the Managers in 1879.

NOTES AND QUERIES.

Oils. (Reply to R. J.).-I think that your correspondent R. J. will find the information he requires in the article on Oils in "Ure's Dictionary." F. C. Calvert has also published a paper in the Pharmaceutical Society's Journal, xiii, 56, upon the Analysis and Detection of Impurities in Oils.-H. A. LAWRANCE.

TO CORRESPONDENTS.

Max Jordan.-We regret that we are unable to give our correspondent the information he desires.

Lavon. Morfit's treatise on Soap, published by Trübner and Co. Merrick.-Apply to the Secretary of the Society at Burlington House for a nomination form, which has to be signed by a certain number of Fellows of the Society, some of whom must have personal knowledge and others general knowledge of a candidate.

3. C. Harvey." Sutton's Volumetric Analysis," published by Churchill.

NEWS

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WE have received from Dr. Theodor Schuchardt, of Goerlitz, a specimen of a new body, which he calls silicium strontium. It is formed from the preparation of metallic strontium by electrolysis, but no particulars are given as to the substances present or the reaction by which it is formed. As received from Dr. Schuchardt the compound is a grey powder with a slight odour resembling phos- In the steel plates, in Nos. II. and III., traces of phuretted hydrogen. When mixed with dilute hydro- copper were observed. The other two steel plates conchloric acid a rapid evolution of the spontaneously in-tained no copper. flammable siliciuretted hydrogen takes place. No particulars as to price are mentioned, but if obtainable in quantity this compound will probably be the readiest source of siliciuretted hydrogen.

W. C.

MEANS OF DETECTING THE ADULTERATION
OF SAFFRON.

To detect adulteration with Calendula flowers (Feminelle), it is merely required to moisten a few flowers, and to rub them singly with the finger on white paper. The genuine flowers will give a fine rich yellow colour, whilst the Feminelle will only yield a violet reddish hue. It can also be easily detected by soaking the suspicious flowers in pure or, better still, distilled water. The real saffron will retain its fine red colour after hours, whilst the Feminelle will lose its artificial tint within a short

time.

To detect an admixture of Honey and Barytes it is merely required to put a pinch of saffron in a tumbler with pure clear water (also in this case distilled water is preferable), and agitating it for a few minutes. Adulterated saffron will at once turn the water cloudy, and even small particles of dust may be seen falling to the bottom, which, on pouring the water carefully out, will be found to be a slimy, sand-like mass. With pure saffron the water will remain clear, showing a fine pure yellow colour, which, according to the quality of the flowers, will be more or less intense. Five or ten minutes suffice for these experiments.

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ABOUT one year ago I had the honour of addressing this Institute on the direct manufacture of iron from the ore. I then briefly referred to the various efforts that had been made in that direction, reaching over the best part of the past century, and closed the paper by describing a method, which, from various experimental and practical tests, seemed likely to promise usefulness in the arts.

It may be remembered, by this process the ore, carbonaceous matter, and fluxes, in the proper proportions, are ground together and mixed at the same time, and then illed into annular sheet-iron cases, holding from roo to 200 pounds. Ten to twenty of these cases, with spaces between them, are subjected to the gradually increasing heat of a reverberatory furnace, and in about five hours on the average the ore and cases settle down, without work upon them, to about one-third their original height, becoming welded into quite compact lumps of iron, interspersed with liquid slag. These metal lumps are either then removed separately from the furnace, or several of them being welded together at the same heat, are forged or squeezed and rolled to "muck-bar."

* A Paper read before the Franklin Institute, November 20, 1878.

36

Direct Process of Making Wrought-Iron and Steel.

This process differs from all others, and it is exactly the reverse of the forge-fire and the blast-furnace methods. In those, a tuyere conducts a stream of oxygen into close contact with the particles of ore, while in this process the moderate heat prevents the combination of phosphorus with the iron, while atmospheric contact is excluded during reduction, and a reflected heat from the roof is furnished, for absorption during the transition to metal. It is to this peculiar treatment that is ascribed the high quality of the iron for steel purposes. It is what may be termed a baking process, which is conducted at a comparatively moderate heat to eliminate phosphorus, and in which the ore is kept out of the reach of oxidising influences, and to this the high value for steel is attributable. At the time I addressed you I had licensed Messrs. Miller, Metcalf, and Parkin, of Pittsburg, Pa., to work the process at their Crescent Steel Works. Their forge and furnace was not completed until some time in last January, when for seveal months thereafter they carefully tested the iron which was deoxidised with charcoal by this method, in the various ways customary to determine the value of iron for high grades of steel. The result of these investigations brought forth the unqualified endorsement of this firm that the iron so produced from our native ores, for steel purposes, is equal in every respect to the most costly grades of

Swedish iron.

Although the production of fine steel iron, reduced with charcoal by this process, was a step forward, yet the consumption of high grades of steel is comparatively limited, being mostly used only for tools of various kinds requiring great endurance. In order to enlarge the uses of this superior make of iron, it became apparent that its cost must be cheapened by deoxidising the ore with waste anthracite dust or refuse coke-dust, instead of charcoal.

To determine the practical value of anthracite dust, a series of more than fifty experiments were conducted, during the month of August last, at the forge at Reading, Pa. In these experiments, with anthracite dust, were used magnetic ore from near West Point, N.Y., Dickinson ore from northern New Jersey, Cornwall ore from Lebanon Co., Pa., Cumberland Valley ore from Maryland, Hematite ore from near Newark, Del., besides several other ores found near the line of the Philadelphia and Reading R.R. These ores were worked both separately and variously combined, and with one exception, in every case, were reduced and forged to blooms. The blooms, which were re-heated, were drawn out smoothly under the hammer. The tensile strength of one of these bars was tried, and found to not exceed 45,000 pounds to the square inch.

A couple of crucibles of steel were made from a part of the iron which had been re-heated and drawn out, and the ingots where forged and used for planing tools. They stood forging and tempering well, comparing favourably, in endurance, with steel usually used in planing iron.

The object of testing iron reduced from the ore with anthracite coal-dust, for tool steel, was not so much with the expectation that at the first trial it would work well in planing iron in competition with steel carefully prepared from charcoal iron, but to determine, in a general way, the quality of the metal for steel purposes, of superio quality and in large quantities, by the open hearth.r The result of this crucible test surpassed expectations and was very gratifying, from the fact that it is believed to have been the first instance where good tool steel was ever made by a direct process, on a practical scale, from iron deoxidised with anthracite coal-dust, and confirms the belief that anthracite dust will eventually be largely used to produce steel of high quality, cheaply and in large quantities.

Besides testing the ores before named, at the Reading forge, iron scale from the rolls (which is almost pure oxide of iron) was reduced alone with anthracite dust, and was also mingled with ore and anthracite, and in both cases was found to forge well into good blooms.

At the same time with the foregoing experiments, the ul pho-oxides or refuse ore remaining after extracting

MICAL NE January 24, 187.

sulphur for sulphuric acid from the iron pyrites, at the New Jersey Chemical Works (commonly known to the trade as "Blue Billy"), was also reduced by this process with anthracite coal dust, and forged well into a bloom. This specimen was some time afterwards re-heated, rolled, cut up, and piled with about one-third of its weight of muck-bar from common puddled iron, and plated out well into smooth sheets of No. 26 iron. This last experiment is not of much value for this country, because very little sulphuric acid is made from pyrites, but in Europe probably not less than a million tons of this refuse ore is now annually almost wasted, because of the difficulty of economically utilising it.

These Reading experiments were the more gratifying from the fact that the process was quite successfully conducted in a reverberatory furnace, not well adapted to the purpose. This furnace had some time before been specially arranged to test the use of anthracite coal-slack, by burning it in fires of 4 or 5 inches thickness, on what is commonly termed "the Wooten grate-bars." As these thin fires required renewal every 15 or 20 minutes, the frequent opening of the door for replenishment exposed the ore so often to atmospheric re-oxidation as to make the furnace unsuited to the process. Besides this, the fire and flue bridge-walls, which had been constructed very low, and could not be very well raised owing to the lowness of the roof, caused the cases of ore to be exposed to the direct action of the blast and draught as it passed through the furnace into the stack.

Following up these interesting experiments during the month of September last, a sand-bottom scrap-heating furnace was altered at the Sligo Iron Works at Pittsburg for the purpose of testing this process further, by throwing the lumps of metal into a Burden Squeezer, and then rolling them to muck-bar" at the same heat. Hitherto they had usually been forged to blooms under a hammer, and afterwards re-heated to be drawn to bars.

This furnace was operated experimentally with 32 heats. There was found no difficulty in making balls to pass through the squeezer and muck rolls at the same heat, just as ordinary puddle balls from pig-iron is squeezed and rolled at the same heat to muck-bar; but in order to fill the squeezer, which required balls of 150 to 200 pounds to secure a good compression, it became necessary to weld and press several of the lumps of meta! together in the furnace at a heat so high as to cause the alkali to drip more or less from the mass, and soften the sand-bottom. As the balls were thus compressed and rolled in the fused sand an unnecessarily large portion of the iron was thereby cut by the sand and wasted to a silicate of iron, so that the yield from Republic ore which, before the bottom became softened, produced 53 pounds of iron in muck-bar from 100 pounds of ore charged, and which it was expected would have been brought up to 60 pounds of iron from 100 pounds of ore, gradually became very much lessened, showing conclusively that reduced yield followed the softening of the bottom, and determined the necessity of a "cinder-bottom" in order to save the iron. To compress and weld several of these masses of metal together in the furnace, in order to have them enter and fill the squeezer, really comprised all the labour required during the heat. The cases were 15 inches diameter and 14 inches high, holding about 135 pounds of ore besides the coke and fluxes. By making the cases very little larger, say 16 inches diameter and 16 inches high, they would each produce about 100 pounds of iron, and by withdrawing each separately to the squeezer, all furnace manipulation of the metal would be avoided. Then, aside from maintaining the fire and charging and discharging the metal, all the labour really needed during the heat would be to change the damper once or twice, enabling an ordinary heater to regulate all the furnaces in the largest mill.

The fire- or grate-surface of this Pittsburg furnace was 4 feet square, and the space between the bridge-walls was 9 feet by 5 feet in width. The bottom was of sand,

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