CHEMICAL NEWS, Oct. 6, 1876.

147

C2HNO2.

and equally unfavorable results were obtained when 14 acid was substituted for the 15. For a time I thought an approximate separation, at least, could be effected with fatty oils or heavy paraffin-oils, but it turned out an illusion; a considerable quantity of ethylen always accompanied the benzol in its absorption by these liquids. The last substance I tried was non-vulcanised indiarubber, and, if I may trust a few preliminary trials, it does seem to have the power of abstracting the benzol from a gas without condensing much of the ethylen. I have, however, not yet found the time for trying exact quantitative experiments.

In order to form an idea of the proximate composition of the olefine portion of Glasgow gas, a current of it was made to pass (1) over dry chloride of calcium, (2) over a coil of sheet india-rubber, and (3) through a long slanting tube charged with bromine. The bromine soon got almost entirely converted into a liquid bromide, which was washed with dilute caustic soda, dried with fused chloride of calcium, and distilled. A considerable portion distilled below the boiling-point of propylen bromide (142°). The percentage of bromine was found to be 83.52, whence, assuming the composition to be CnH2nBr2, we have

CnH2n=316; C2H4=28; C3H6=42.

When a weighed quantity was treated on a water-bath with alcoholic potash, a large precipitate separated out, which was found to contain more than half of the bromine originally present in the substance.

These experiments clearly show that the substance consisted substantially, not of mono-bromo-benzol (C6H5Br, which is not decomposable by alcoholic potash), but of bromides, CnH2nBr2, in which the lowest term, C2H4Br2, must have been very largely represented.

From the foregoing it is clear that, contrary to Berthelot's assertion, the constitution of the heavy carburetted hydrogen portion in coal-gas is pretty much what it has always been supposed to be.

I have to thank my friend Mr. W. J. Curphey for the excellent manner in which he has assisted me in this little investigation.

Anderson's University, Glasgow, September, 1876.

NOTE ON A NEW CORNISH MINERAL. By FREDERICK FIELD, F.R.S.

MR. TALLING, of Lostwithiel, Cornwall, called my attention to a highly crystallised and very beautiful Cornish mineral which is quite new to mineralogical science. Its crystallisation appears to be rhombic; it is transparent and brilliant, of a clear green colour; hardness about 3'5. It is perfectly soluble in dilute hydrochloric acid, forming a nearly colourless solution. On heating a little over 100° C., the crystals lose water, and at a low red heat at once become brilliantly black. They decrepitate strongly. Analysis proved the existence of phosphoric acid, ferrous oxide, and water in the proportions that would lead to the formula

BY

NASCENT HYDROGEN.

By WILLIAM SKEY, Analyst to the Geological Survey of New Zealand.

THE fact that Prof. Storer* has based a method for the

direct determination of lead in galena upon the deportment of this ore with zinc and hydrochloric acid, discovered by me in 1870t, induced me to further investigate decompositions of this nature, and the results of this show that stibnite, in contact with zinc and hydrochloric acid, instead of evolving HS as when zinc is omitted, evolves HSb only, that is, at least, during the earlier part of the time in which decomposition is going on. Mispickel, in like manner, first gives off HAs.

It will be seen, therefore, that metallic sulphide can be directly tested for either of these metals in the way indicated above, in conjunction, of course, with slips of paper moistened with a lead salt, and other slips moistened with

a silver salt.

For experiments of this kind it is best to use the acid weak, the zinc amalgamated, and the ore coarsely crushed

(1.)

NOTES OF WORK BY STUDENTS OF PRACTICAL CHEMISTRY

IN THE

LABORATORY OF THE UNIVERSITY OF
VIRGINIA.
No. V.

Communicated by J. W. MALLET,

Professor of General and Applied Chemistry in the University.

Analysis of the Ash of the Ground-Pea (Arachis Hypogaa) as Cultivated in Virginia. By WILLIAM G. BROWN, of Albemarle Co., Virginia. The pea-nut, also known by the trivial names groundpea, gouber-pea, and pinda, is a plant cultivated pretty largely in the south-eastern counties of Virginia, near the sea-coast, and in the adjoining part of North Carolina. The nuts, developed on a slender underground stem, are shipped to various parts of the country and sold to be eaten as a sort of cheap luxury after they have been roasted like chestnuts. In France they are extensively employed in making by expression a fine, bland oil, the supply being brought chiefly, if not solely, from the West Coast of Africa and Algiers. The haulm forms excellent forage for cattle. The oil has been the subject of chemical examination by Goessmann and others, but the only record of any study of the plant itself seems to be that contained in the "Report of the United States Department of Agriculture" for 1870 (p. 92), with the quotation there made from the "Transactions of the Highland and Agricultural Society of Scotland" (vol. vi., p. 556). Dr. Antisell, Chemist to the Department of Agriculture, gives merely the proximate composition of the seed and husk in but a rough sort of way, since albuminoid matter and starch are reported together, and the figures given for seed and husk separately will not agree arithmetically with those for the two together, and puts the ash at 1'77 per cent (seed) and 11'90 per cent (husk); saying only as to its composition, that in the case of the seed it consists of salts wholly soluble in water, being phosphates of the alkalies with traces of alkaline chlorides and sulphates, while the ash of the husk contains, chiefly common salt and phosphates of lime and magnesia. The quoted analysis is by Dr. Anderson, also approximate, and applies to the cake or marc after expression of the oil. He gives the amount of ash as 3.29 to 3.78 per cent, and says that it contains 114 to 117 of phosphates and o'08 to 0'52 of "Select Methods of Analysis," by W. Crookes, F.R.S., p. 214.

↑ Phil. Trans. o New Zealand Institute, vol. iii., p. 222.

CHEMICAL NEWS,

Oct. 6, 1876.

Pure ash..

TABLE VI.

(In 100 parts dried at 100° C.)

Root.

Stem.

Leaves.

13.288 7'747

Husk.

Seed. 1.818

11.830 2:586 Besides thus examining the ash, the percentages of oil and of nitrogen were determined in the seed-the former by repeated and thorough extraction with ether, using atmospheric pressure to force the liquid through a tall percolating tube into a partially exhausted flask, the latter by combustion with soda-lime.

Two specimens of air-dried seed gave 47°34 and 47'44 per cent of oil respectively. This amount is greatly in excess of the figures given in the Agricultural Department's Report above referred to, Dr. Antisell having found only 16 per cent in the Virginia seed, while that of Algerian growth, it is said, on the authority of Dr. Anderson, "furnishes 25 to 27 per cent," to which is probably to be added 6.78 to 12.75 per cent found in the cake.

The nitrogen in the air-dried seed amounted to 3'415 per cent, representing about 22 per cent of albuminoid matter, or nearly the same as in the common pea or bean.

(To be continued.)

REPORT

ON THE

DEVELOPMENT OF THE CHEMICAL ARTS
DURING THE LAST TEN YEARS.*
By Dr. A. W. HOFMANN.

(Continued from p. 139.)

Chlorine, Bromine, Iodine, and Fluorine.

By Dr. E. MYLIUS, of Ludwigshafen. WHEN, in consequence of the extensive opening of manufactories for the utilisation of the "abraum" salts, an over-production of the salts of potash occurred, other establishments felt induced to enter upon the preparation of bromine, but without accomplishing anything worthy of note in this direction.

Rich sources of bromine were also discovered in North America, and have been worked with great success.

The product, however, does not arrive in Europe as liquid bromine, since ships do not generally receive it among their cargo. It is exported chiefly as bromide of potassium. But considerable as is the quantity of bromine produced in North America there is no foundation for the fear that it may occasion any appreciable depression of the Stassfurt trade, since bromine is obtained in America as a main product, whilst in Stassfurt it plays merely the part of a by-product of the potash manufacture.

The demand for bromine and its compounds depends on its applications in medicine, photography, and scientific chemistry. The hope of seeing its hydrocarbon compounds extensively employed in the manufacture of coaltar colours in place of the corresponding iodides has not been fulfilled, in spite of the present greatly increased price of iodine. One obstacle which stood in the way of the application of brom-ethyl and brom-methyl for the purpose in question, i.e., the great volatility of these compounds, has been overcome by Dr. A. W. Hofmann, who proposes to cause bromamyl-which boils at the far higher temperature of 120°-to act upon the coloured bases, to be ethylated or methylated simultaneously with methylic or ethylic alcohol, thus forming brom-ethyl or brom-methyl along with amylic alcohol. Still the small

"Berichte über die Entwickelung der Chemischen Industrie Während des Letzten Jahrzehends."

A. W. Hofmann, Ber. Chem. Ges. 1869, 441.

149

reactive power of the bromides as compared with the iodides, the inferior brilliance of the colours produced with the aid of the former, the difficulty of recovering the bromine as completely as iodine in consequence of its volatility, have prevented bromine from effectively competing with iodine in this department. Still the hope that bromine may on further investigation attain importance in tinctorial chemistry has not been abandoned. Certain manufactories, both English and German, use a mixture of brom-ethyl, which boils at about the same temperature as iod-methyl and brom-methyl. The reporter is informed on good authority that the colour works of Huddersfield and of Barmen still draw large supplies of bromine from Stassfurt.

The use of bromine as a disinfectant in the form of an aqueous solution, introduced during the North American and Franco-Prussian wars, has remained very limited although it possesses several advantages as compared with chloride of lime. In hospitals the use of bromine occasions much less irritation in the respiratory organs than that of chlorine.

Although, as has been stated, bromine finds scarcely any application in great manufacturing operations, its production is still important, as appears from the report of Chandler. According to this authority 62,500 kilos were annually obtained in North America alone in 1869 and 1870, principally in Tarentum, Sligo, Natrona, Pomeroy, Ohio, and Kanawha. Stassfurt produced in the year 1873, 20,000 kilos.; and England and France together about the same quantity.

From the foregoing it will be readily inferred that there is little novelty in the methods of extracting bromine. Leislerf took out an English patent for a method of obtaining bromine and iodine. He decomposes the bromiferous lyes with a mixture of hydrochloric acid and bichromate of potash in an iron still furnished with a capital of lead or stoneware. The vapours of bromine along with water are led into a receiver containing iron turnings. Bromide of iron is formed, which dissolves in the water, and is either converted into other metallic bromides by the customary methods, or is treated for free bromine with sulphuric acid and bichromate of potash. This process has never been reduced into practice, and for Germany at least appears too expensive.

In Stassfurt, therefore, the method has been followed which had been used for the extraction of bromine in the salt works of Schönebeck, Artern, and Neusalz, consisting of the following operations:-The mother-liquor of carnallite at 35° B. freed as far as possible from chloride of calcium by refrigeration, is concentrated to 40° B. by further evaporation. According to Frank the concentration cannot be carried so far, as, in consequence of the partial overheating of the lye at the bottom of the pan, bromine is inevitably wasted in the form of hydrobromic acid. On cooling to 25° a quantity of chloride of magnesium, MgCl2+6H2O, and the remaining mother-liquor contains from o'3 to 0'5 bromine as bromide of magnesium. It is placed in a sandstone apparatus resembling those used for the preparation of chlorine with the corresponding quantity of manganese and hydrochloric acid, and heated by the introduction of a current of steam. vapours which are evolved about a quarter of an hour after the steam is turned on are condensed in a lead worm, cooled in water, and are collected as liquid distilled in glass retorts for further purification. A sandbromine in Woolff's bottles. The crude bromine is restone apparatus can be charged six times in twenty-four hours. In order to obtain the bromine free from chlorine it is agitated with a solution of bromide of potassium, from which bromine is liberated equivalent to the chlorine present, whilst chlorine of potassium is formed (Falières).

To be continued.)

*H. Chandler, CHEMICAL NEWS, 1871, No. 586, p. 77.

The red

4 L. Leisler, Dingl. Pol. Journ., clxxix., 386. Wagner Jahres

bericht, 1866, 179.

F. Michel, Wagner Jahresbericht, 1867, 194.

150

NICKEL AND SILVER ALLOY.

By Major W. A. ROSS.

MESSRS. JOHNSON and MATTHEY, of Hatton Garden, gave me for analysis by the blowpipe some fragments of the result of a fusion together of the metals silver and nickel, in which the silver (a) was on one side, apparently perfectly white and pure, and nickel at the other, of a dark grey colour (b).

1. A minute speck of (a), treated at the bottom of a phosphoric acid bead in P.P.,* afforded a nearly colourless transparent bead, which, treated with a momentary H.P., became covered with the semimetallic coating on the surface, which shows 5 per cent of the bead to be silver solution.

2. (b), in a similar fragment and bead, gave the same reaction, but was also nut-brown hot, and orange cold, showing a large proportion of nickel.

It seems, therefore, that nickel in fusion will take up silver to a considerable extent, but that silver refuses to combine similarly with nickel.

October 4, 1876.

ON THE

PHYSICAL PROPERTIES OF GALLIUM.

By M. LECOQ DE BOISBAUDRAN.

I HAVE recently prepared rather more than half a grm. of pure gallium. In the liquid state this metal is of a beautiful silver-white, but on crystallising it takes a very decided bluish tint, and its lustre notably diminishes. On properly effecting the solidification of superfused gallium isolated crystals are obtained: these are based octahedra, which I am engaged in measuring.

On a first trial (April, 1876) the point of fusion was found between 29° and 30°, or near +29.5°. I have just examined six samples of gallium successively electrolysed from one and the same solution. The foreign metals, supposed to be present, ought to distribute themselves unequally among the different fractions collected:

Gallium, No. 1.

2.

Points of Fusion. +30'14°

30.16

The sample No. 4 was afterwards placed for two hours in boiling water, and the innumerable globules formed were united by compression. The point of fusion had not varied. The metal was therefore very free from potassium. The six samples of gallium having been mixed, a fragment was taken (weighing 2 centigrammes), which was kept for half an hour in nitric acid diluted with its own volume of water at a temperature of 60° to 70°. The loss only reached a fraction of a milligramme. The point of fusion remained fixed, for the metal melted very slowly at +30°16, and crystallised very slowly at +30'06°. I shall shortly have the honour of submitting to the Academy the new process which served for preparing this gallium, of which the constant point of fusion denotes a very satisfactory purity.

In May, 1876, I tried to determine the density of gallium on a sample of 6 centigrammes: I obtained 4'7 at 15° (and with reference to water at 15°). The mean of the densities of aluminium and indium being 4.8 to 5'1, the provisional specific weight found for gallium appeared to agree tolerably well with a theory placing this metal between indium and aluminium. However, the calculations

* See "Pyrology," pages 56 to 58.

CHEMICAL NEWS, Oct. 6, 1876.

established by M. Mendeleef for a hypothetic body, which seems to correspond to gallium (at least according to many of its properties), would lead to the number 5'9.

Gallium crystallised under water decrepitates sometimes when heated. Perhaps my first metal contained interstices filled with air or water. I am ignorant if this cause of error is combined with others so as to falsify my first determination. However this may be, I avoided it subsequently by heating the metal strongly and solidifying in a dry atmosphere. I then obtained higher densities, varying from 5'5 to 6'2, although the weight of the trial samples did not exceed a few centigrammes.

I finally operated with 58 centigrammes of gallium derived from the union of six samples mentioned above. Density at +23° (and referred to water at +23°)— First experiment.. Second experiment

Mean..

5'900 5'970

5'935

rature.

The present issue contains the Rules of the Society as adopted at its first meeting, on February 3rd, 1876, and an account of the papers read at the Ordinary Meeting held on February 4th, and at the Local Meeting of the Cornish members at Redruth, July 1st.

These pages comprise a note, by Mr. Marshall Hall, upon a portion of basalt from the Mid-Atlantic, fished up by the steamer Faraday whilst grappling for a broken telegraph-cable. The question arises whether the fragment has been wrenched off some submarine ridge, or whether it is an ice-borne mass deposited by an iceberg. Mr. W. W. Stoddart contributes a paper on the "Occurrence of Celestine in the Keuper Marls, and its Influence on the Composition of Plants." The author has discovered strontia in the ash of eight plants, including the common dandelion and groundsel, found growing on the Keuper marls, on the north-eastern side of Cotham Hill, near Bristol.

Mr. C. Le Neve Foster read a paper on "New Minerals and Mineral Localities in Cornwall and Devon." The species described are-Henwoodite; Pyrophyllite, found for the first time in England at Brookwood Mine; Eny. site, from St. Agnes; Actinolite, with green garnets; and Aximite, from S. Terras and South Brent.

Mr. Collins also described Henwoodite and Enysite, and gave a notice of the occurrence of Scorodite, Pharmacosiderite, and Olivenite, in the greenstone at Terras Mine, St. Stephens.

Mr. Vivian communicates a note on "Paragenetic Formations of Carbonate of Lime and Oxide of Iron, and of Quartz and Oxide of Iron, at the Mwyndy IronMines, Glamorgan." Mr. J. H. Collins also furnishes an additional note on the species described by Mr. Vivian.

Mr. C. Le Neve Foster describes and figures a new form

Stanley's Metre-Diagram, Illustrating the Metric System with Explanations, Tables of Length, Surface Capacity and Weight, Rules, Approximate Equivalents, &c. A. and T. W. Stanley, New Britain, Connecticut. THIS is a useful pocket companion intended to facilitate an understanding of, and prepare for the introduction of, the metric system of weights and measures. On a folding slip of "artificial parchment," which, by the way, appears to be an excellent material for plans, maps, and the like, requiring to be folded up, is engraved at full size the standard yard of England and America divided into inches and tenths of an inch, Parallel with it is a meter, graduated into decimetres, centimetres, and millimetres, so that the conversion of any lineal measure from the one standard into the other can be effected at a glance. Another diagram, all on the same slip, shows one decimetre with its subdivisions placed side by side with the approximately equal measure of four inches. The remainder of the space is utilised for a brief exposition of the advantages of the metric system, an account of its units, with tables of approximate equivalents, and rules for conversion. The back of the slip is occupied with views of the Philadelphia Exhibition building, wiih the dimensions stated on both systems.

We heartily wish that some unanimous decision concerning weights and measures could be reached by the civilised world. As regards the metric system England and America seem each to be waiting for the other. A commission of engineers, &c., entrusted by the Franklin Institute with the task of examining into the question, reported against the new weights and measures. their arguments was, that as something like three-fourths of the entire foreign trade of America was carried on with Great Britain and its dependencies, the introduction of the metric system would rather hinder than facilitate

business.

CORRESPONDENCE.

PROF. DITTMAR AND THE

One of

"ANALYST."

To the Editor of the Chemical News. SIR, -The subject of the recent attack on Prof. Dittmar was brought before the notice of the Glasgow Meeting of the Public Analysts, and the attack was condemned by those present at the meeting. So decided was the expression of condemnation that a vote of censure on the Committee of Publication was even mentioned; but in place of so extreme a course (which in my opinion ought to have been followed) an indirect vote of censure was carried, the resolution being to the effect that before commentaries on adulteration-cases are inserted in the Analyst

the chemists implicated should be communicated with.

I observe that the current number of the Analyst purports to give an account of the Glasgow Meeting of the Society, but does not in any way record the resolution passed at that meeting. I observe also an editorial commentary on Mr. Dittmar which is in direct opposition to the resolution passed by the meeting; and I take this opportunity of making known that the Society of Public Analysts has no real control over the Analyst, which is the property of Mr. Wigner and Dr. Muter, who alone are responsible for the contents of the paper.-I am, &c., J. ALFRED WANKLYN. Laboratory, 117, Charlotte Street, Fitzroy Square, October 2, 1876.

115

DR. LUNGE'S APPARATUS FOR MAKING CHLORATE OF POTASH.

To the Editor of the Chemical News. SIR,-In the translation of Dr. Mylius's Report on Chlorine, &c." (CHEM. NEWS, vol. xxxiv., p. 139) there is a quotation from a paper of mine, published nearly ten years ago, which might mislead your readers as well as those of the original German Report. Dr. Mylius quotes my description of a small apparatus for making chlorate of potash as if I had stated that form of apparatus to be in general use in England, whilst the contrary will at once be apparent to any reader of my original paper in Dingler's Polytechnisches Journal. The apparatus in question would only suffice (as stated by me) for making 7 cwts. of potassium chlorate per week.

Dr. Mylius also quotes a proposal of mine for obtaining powdered potassium chlorate by disturbed crystallisation. I do not now think that that proposal is worth very much, for, in the first instance, the powder thus obtained would not be anything like fine enough for the users of that article, and would thus have to be passed through a mill anyhow; secondly, manufacturers of that article have always a considerable quantity of siftings from the coarser crystals on hand, which can only be advantageously worked up by grinding them to powder. The danger of grinding potassium chlorate-which I apprehended at that time to be very considerable-I have not, after some years' practical experience, found to be very great, provided the material is kept clear from splinters of wood or bits of iron, and the mill is not allowed to get hot.I am, &c., GEORGE LUNge.

Zürich, October 4, 1876.

CALCULUS IN HORSES.

To the Editor of the Chemical News. SIR,-I have been investigating the nature of the concretions found in the large intestine of horses, and I trust to be able in a short time to communicate to your journal the full details and analyses of these calculi.

In the meantime allow me to observe that we lose a considerable number of valuable horses every year by this terrible disease, particularly those devoted to labour in the iron districts, which animals are generally very fine and powerful, and highly fed. One of my relatives has lost in this way no less than five splendid horses within a short space of time, and millers' horses are very liable to the disease both here and on the Continent.

The calculi are formed in the large intestine (cæcum); they begin often by being triangular, or sometimes perfinally circular. In all cases they are formed of highly fectly square, with rounded edges and corners, and become crystalline concentric layers, and attain to 18 or 20 inches in diameter, that is, as large as an ordinary gas-lamp globe. I believe that this is the greatest size they can arrive at, and that when so large as this, they already press out the sides of the intestine, producing inflammation and violent pain, which causes the animal to roll about in agony, and sooner or later kills him. I have met recently with two calculi of this enormous size, both cases being Staffordshire horses.

The usual remedy, as far as I have ascertained, has been, hitherto, some powerful purgative, chiefly aloes; and when the calculi are small or recently formed-not But when larger than walnuts-this appears to answer. large such treatment only increases the evil.

I find that the greater bulk of these calculi, large or small, consists of phosphate of ammonia and magnesia, and when a portion of the pulverised calculus is heated over a spirit-lamp on a platinum dish, it shows that very curious phenomenon of incandescence, or rather phosphorescence, peculiar to this salt at a certain temperature. The amount of organic matter is not great, but I have