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Science Scholarships.

LESSONS IN ELECTRICITY, at the Royal effected to all parts of the world.

PATENTS: Mr. Vaughan, F.C.S., British

CHEMICAL News,
Nov. 10, 1876.

207 The students at this college have, he says, never yet been

, Kenequalled at the London University examinations by the nington Road. Managing Director, Dr. MUTER. students from any of the other colleges in the United Daily Lectures on the following subjects:Kingdom. They have hitherto invariablyobtained honoursin

CHEMISTRY.

MATERIA MEDICA.
BOTANY.

PHARMACY. chemistry. In 1870 a University Exhibition was established.

PHYSICS.

CLASSICS. It was not awarded in the first two years. The College

The School has accommodation for 120 Students, and contains an of Science gained it both in the filth and seventh years. excellent Museum and a very completely fitted Chemical Laboratory No other institution has taken it twice, and it has only for 50 Junior and 20 Senior Pupils, with water and gas at every working been gained once by three others-viz.,

uy's Hospital, bench.

For all particulars, enclose a stamped envelope to the Secretary, University College, and the School of Mines. The com

Mr. W. Baxter, at his office, Central Public Laboratory, Kennington petition for honours is very severe. Sixty students went Cross, London, S.E. in this, the seventh, year of the exhibition, and only ten passed, and two of such were students, and the only BERNERS COLLEGE OF CHEMISTRY,

in conjunction with the SCIENTIFIC DEPARTMENT of the students, from the College of Science.

ROYAL POLYTECHNIC INSTITUTION.

Instruction and preparation in CHEMISTRY and the EXPERI.

MENTAL SCIENCES under the direction of Professor E. V. MEETINGS FOR THE WEEK.

GARDNER, F.A.S., M.S.A.

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daily. THURSDAY, Nov. 16th.-Chemical, 8. "On Barwood," by the late Especial facilities for persons preparing for Government and other

Dr. Anderson. “On Potassium Tri- examinations.
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existing kinds), large Collections of Fine Hyacinths in all Colours Novacastrian.-We have only seen the advertisements and pro

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London, W.C., and 8, Houndgate, Darlington.
A SYSTEMATIC HANDBOOK

INDIA-RUBBER SPECIALLY PREPARED FOR
VOLUMETRIC ANALYSIS;

CHEMICAL PURPOSES.
Boots, Gloyes, Gauntlets, Aprons, Pure Tube and

Hose, all Warranted Best Quality.
Quantitative EstimaTION of Chemical SUBSTANCES
BY MEASURE, APPLIED TO LIQUIDS, SOLIDS, AND Gases. J. G. INGRAM & SON,

Adapted to the requirements of Pure Chemical Research, Patholo- Manufacturers of Mechanical, Surgical, Chemical, and gical Chemistry, Pharmacy, Metallurgy, Manufacturing Chemistry

all other Vulcanised India-Rubber Goods. Photography, &c., and for the Valuation of Substances used in Com. merce, Agriculture, and the Arts.

The London India-Rubber Works, Hackney Wick, E.,
By FRANCIS SUTTON, F.C.S.

AND AT HOXTON AND RAINHAM, Essex.
J. and A. CHURCHILL, New Burlington Street.
Now ready, New Edition, 8vo., 7s. 6d.,

creates no waste or dust by its magnetic adherence to the stove,

and the cleanliness of application makes this one of the marvels of CHEMIA COARTATA:

household economy-Sold by all respectable grocers and oilmen in

blocks 1d., 20., 4d., and is. boxes. Works, 91, Little Compton Street, OR, THE KEY TO Modern CHEMISTRY.

Soho, London. By A. H. KOLLMYER, A.M., M.D., Professor of Materia Medica and Therapeutics at Montreal. hemical Technology, or Chemistry in its J. and A. CHURCHILL, New Burlington Street.

Applications to the Arts and Manufactures. By Tномля RICHARDSON and HENRY Watts. Second Edition, illustrated with

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Vol. I., Parts 1 and 2, price 36s., with more than 400 Illustrations. WINTER SESSION, 1876-77.

Nature and Properties of Fuel: Secondary Products obtained from Fuel: Production of Light: Secondary Products of the Gas Manu. facture.

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October 9th, and terminate in March.

Sulphur and its Compounds: Acidimetry: Chlorine and its Bleaching CHEMISTRY--Mr. W. N. Hartley, at 7 o'clock. Mondays and

Compounds: Soda, Potash : Alkalimetry: Grease.
Thursdays. Fee, £IIIs. 6d.
ANALYTICAL CHEMISTRY-Tuesday from 7 to 9. Fee, £2 28.

Vol. I., Part 4, price 218., 300 Illustrations.

Aluminium and Sodium: Stannates, Tungstates, Chromates, and REFINED ANTHRACENE

Silicates of Potash and Soda : Phosphorus, Borax: Nitre : Gun.

Powder: Gun Cotton.
AND OTHER

Vol. I., Part 5, price 36s.
COAL-TAR PRODUCTS.

Prussiate of Potash: Oxalic, Tartaric, and Citric Acids, and Appen.

dices containing the latest information, and specifications relating to HENRY SCHOLEFIELD,

the materials described in Parts 3 and 4. Cleadon Chemical Works, Newcastle-on-Tyne.

BAILLIERE AND Co., 20, King William Street, Strand.

OF

OR THE

Ryall's Chemical Black Lead (Registered)

Chemi

The Evening Lectures commence on Monday,

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EXTENSIVE WORKS, MACHINERY,

STOCK-IN-TRADE,

AND GOOD WILL OF THE

HEREFORDSHIRE AND SOUTH WALES MANURE COMPANY,

(LIMITED.)

The Works are most desirably situated at HOLMER, within the Liberties of the City of Hereford and are well adapted for carrying on a Large Trade; and there is a large and increasing demand for Artificial Manures in the County and surrounding Districts.

Apply to MR. T. F. SALMON, the Manager, NOVEMBER 6Th, 1876.

HOLMER, near HEREFORD.

ESTABLISHED 1798.
S. A. SADLER,
CLEVELAND CHEMICAL WORKS,

ROBERT DAGLISH & Co.,
MIDDLESBROUGH;
Newfali Tar Works, Carlton;

BOILER MAKERS, ENGINEERS, AND and Ammonia Works, Stockton-on-Tees.

MILL-WRIGHTS, Manufacturer of Benzole, Toluole, Xylol, BRASS AND IRONFOUNDERS,

Solvent and Burning Naphthas, Carbolic Acid and Disinfecting Powder, Refined Anthracene, Naphthaline, Black Varnish, Refined ST. HELEN'S FOUNDRY, LANCASHIRE, Tar, Crude Liquid Ammonia, Galvanising Salts, Coal-Tar, Pitch Creosote, Grease, &c., &c.

Makers of every description of Chemical, Colliery, Copper Ure, Gold S. A. S. is always a buyer of Coal-Tar Naphthas, Crude Anthracene and all Tar Products.

Mining and Glass Machinery, including Crown, German Sheet, and

Plate Glass Plant, as supplied to some of the largest Firmsin England, All communications to be addressed to the offices at Middlesbrough.

Ireland, Scotland, and Wales.

Makers of the latest Improved Revolving Black Ash Furnace with Siemens's Patent Gas Arrangement, and as used in the Manufac. ture of Soda.

Improved Valveless Air Engines, and Pumps or Acid Forcing, Air
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Process.
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STEEL PENS.

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Licensed Maker, Commercial Street, Shoreditch, N.E. Circular Roofs, Building, &c., contracted for by

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Water-glass, or Soluble Silicates of Soda
CHEMICAL ENGINEER AND CONTRACTOR,

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ur in solution, at ROBERT RUMNEY'S, Ardwick Chemical 148, STRETFORD ROAD, MANCHESTER. Works, Manchester.

JOHN GRAHAM,

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97. Two other forms of the bulb-apparatus require mentioning. A thin glass bulb was blown 21 inches in diameter (fig. 4). Inside this another bulb was blown 2 inches in diameter, at the end of a glass tube 12 inches long. In this a light glass index with pith terminals was suspended, and the whole was perfectly exhausted. Fig. 4 shows the complete arrangement. In the space between the two bulbs various liquids were enclosed, such as water, solutions of sulphate of copper, alum, perchloride of iron, sulphate of iron, bichroma te of potash, sulphate of nickel, &c. These were selected in the hope that amongst them one would be found which would sift out the heat-rays, and so allow me to obtain an action due to light. They, however, only affect the dark or extreme red heat-rays, and do not affect the luminous rays which also have a heating effect. By throwing a beam of sunlight on one of the pith disks powerful repulsion was obtained,

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210

Anthracen Production.

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CHEMICAL News,

Nov. 17, 1876.

bulbs were blown one in the other, and they were fused to become inevitable, and that in no distant time, the together at the necks; to the neck a small tube was fused serious consequences of which it may well be worth while for connecting with the Sprengel pump. The space to weigh and to consider beforehand. between the two bulbs was then perfectly exhausted, and We all recollect the profound sensation created by the the small tube sealed up. I thus possessed what might grand discovery of artificial alizarine and its manufacture be called a spherical shell of vacuum surrounding a bulb on the large scale, which last commenced only five or six open to the air. In this inner bulb was suspended a pith years ago. In recalling the sanguine expectations raised ball on the end of a glass arm balanced by a knob of glass by this new industry, its present dismal position appears on to the other end, the suspending fibre being protected scarcely credible, and yet the fact stands out only too by a glass tube fitting into the neck of the inner bulb with clearly that no other branch of chemical industry, inaua cork. It was found that heat applied to any part of the gurated under such bright auspices, has in its results outer bulb passed across the vacuum, and attracted the failen so short of just expectations,-nay, I might also pith ball (suspended in air). The spherical shell of vacuum say, has become so disastrous to nearly all persons who across which the heat passed, therefore, produced no remained engaged in its pursuit. True the first pioneers change of action, but simply behaved like an extra thick --those who were actually at work while the first exciteglass

bulb. This experiment bears upon the speculation ment was at its height-were wise enough to sell their in par. 81 of my former paper on this subject.

fortunes at prices which brought them large profits. First 99. Having succeeded in proving the fact of repulsion among these stood Messrs. Gessert Brothers, who sold resulting from radiation, I was desirous of getting some their at that time flourishing concern to a Company, and quantitative estimations of the forces under examination. the English alizarine manufacture, which has since changed A pendulum-apparatus was constructed as shown in fig. 6. hands a second time. A wide glass tube (a b) has fused to it a narrower tube Putting aside a very few German alizarine makers, who (cd), about 40 inches long; e is a turned mass of magne. profess to work at a profit, we have at present a dissium, weighing 42 grains, suspended by a very fine heartening list of many large undertakings who are hopeplatinum wire, the distance between the point of suspen- lessly insolvent, or at least uncomfortably near to it. sion and the centre of gravity of the magnesium bob being In Germany all public companies are very properly 39*139 inches, so that it forms a seconds' pendulum; f is compelled by law to publish their annual balance-sheet a spiral made of platinum plate, fastened to two stout in at least three newspapers, and such document-pubcopper wires which pass through the thick plate of glass b, lished only on the roth inst., in the Cologne Gazette-by and thence pass to a contact-key and a battery. The the “Chemische Industrie Actien Gesellschaft zu Elberplate b is cemented (83) to the end of the tube a ), which feld,” formerly Gessert Brothers, tells its own tale in a is ground flat. g is an arm fused into the upright tube few figures. This official document informs the sharefor the purpose of connecting it to the glass spiral of the holders that the loss of the twelve months' working, pump; it is contracted at h for convenience of sealing off. ending at Midsummer last, amounts to £40,000 ; and as this The fine platinum wire is fastened at its upper end to a

dismal statement is merely a repetition of previous equally thick wire which is sealed into the glass, and passes unsatisfactory balance sheets, there seems to be little through to the outside for electrical purposes (120). The doubt that at next month's general meeting the Company distance between the pendulum bob and the spiral is will be wound up, and that very likely the whole capital 7 millims.

To ignite the spiral the current from two amounting to some £180,000—will be lost. Grove's cells was used; this brought it to a bright red Again, a private firm, Messrs. Schøneberg and Hufheat in air, and to a white heat in vacuum.

schmidt, also of Elberfeld, recently suspended payment, Three feet from the pendulum a telescope was firmly with liabilities estimated at £90,000 and assets £60,000, clamped to the bench; it was furnished with a micrometer or a deficit of £30,000. eyepiece, with movable spider threads and graduated The “ Stueckfärberei Gesellschaft" and the “ Elberfeld circle. The edge of the magnesium bob was brought into Aniline and Alizarine Gesellschaft,” also joint-stock comthe same focus as the traversing cross wire. Observa. panies, are defunct for some time, their capital having tions were taken in the following manner :-The observer | been entirely lost. at the telescope brought the cross wire to zero, and then Plain facts like these—and the list might easily be made adjusted it to coincide with the edge of the pendulum bob. more complete—may well lead to an inquiry into the An assistant, guided by a seconds' watch, pressed the con- cause of such calamity. It may be justly argued that tact-key down for one second, then broke contact for a bad management, want of skill or proper knowledge in second, next made contact for the third second, and so the manufacture, and, above all, the general depression in on, alternately making and breaking contact for either 10, all trades, especially in the cotton trade and everything 20, or 40 seconds, counting the seconds aloud. At each depending upon it, have a great deal to do with the nonsecond the swing of the pendulum increased; and the success of so many undertakings; but I believe the real milled head of the micrometer was kept turning so as to and primary cause to be the most unhealthy state of the let the cross wire keep up to the furthest point to which anthracene manufacture. the pendulum vibrated. At the end of the experiment the The fact is the production of anthracene far exceeds its position of the cross wire was taken and its distance from demand, which, suddenly sprung up some years ago, zero recorded.

tempted many distillers to manufacture an article of a (To be continued.)

very doubtful quality; competition unreasonably ran up the price of tar, and the principal benefit was pocketed

by the gas companies, and by them alone. ON ANTHRACENE PRODUCTION.

I am induced to give a few figures, which will clearly

show this disproportion, and which I feel sure will be By Dr. FREDERICK VERSMANN.

very near to the actual truth, because I have every reason

to depend upon their correctne:s. My investigation on anthracene testing, published in the Up to the end of 1877 there will be produced in England last three numbers of the Chemical News, has brought alone, including present stock, at least 1400 tons of pure me many inquiries and communications, which induce me or 100 per cent anthracene. The requirements of all the to supplement this purely scientific investigation and its alizarine works at present do not exceed 2 tons a day, or practical application by some remarks on the commercial 600 tons a year, of pure anthracene. The next year is aspect of anthracene manufacture generally; and I do so expected to see a considerable increase, but if with presimply because I think my information may enable me, sent low prices we even double the quantity-making it perhaps, to throw sone light upon this imporiant ques

1 200 tons-England alone will produce 200 tons of pure tion, and also because a crisis in this manufacture seems anthracene more than required.

CHEMICAL News,

Nov. 17, 1876.

Anthracen Testing.

211

But it must not be forgotten that the Continent also, cene, viz., anthraquinone (C14H802) an intermediate and supplies large quantities. The Paris Gas Company utilise valuable article in the manufacture of artificial alizarin. their own residues, and produce, together with the other It is unquestionable that the ascertaining of the portion, large French towns, at least 250 tons. Belgium-and which, in more or less crude anthracene, undergoes an more so Holland-is very active, and the production in oxidation by the above method and shows itself as residue, Germany, especially in large towns, such as Berlin and fairly forms a guidance for the alizarine maker as to the Hamburg, is not inconsiderable, and even America sends corresponding quantity of alizarine which can be yielded her quota, if not in large quantities. Altogether there therefrom, and consequently this test has a reasonable will be during 1877 an excess of many hundreds of tons basis ; but how far-chemically speaking—it may be of pure anthracene, and consequently low prices. The correct is the question at issue, equally important to inevitable reaction will produce a reduction in the price of anthracene as to alizarine makers. tar, which already shows itself in Germany. A paper Since the original anthraquinone test came into use I there offers repeatedly, and for some time, six tar contracts have always been at a loss to understand why the weight without any response : the distillers bide their time, and of the oxidised residue should be calculated by a certain their English brethren will soon find out, if they have coefficient (0-856) into"pure anthracene," and sold by the not done so already, the necessity of this line of action. number thus obtained instead of by the original weight of

But-and here I come to the main point of my argu- the residue, because, I may say, nearly all coal-tar disment insisted upon in previous communications--the tar tillers, even those who work under the direction of efficidistiller must feel to find his advantage in the manufacture ent chemists, have unpersuadedly to believe that the of a better and purer article. He must return to the specific gravities of quinone and anthracene are in proporearly times of his operations, when with low tar prices a tion like 1000 : 856; and also because the residue itself moderate price for anthracene paid him well.

is the very article the alizarine maker requires and should The large stock accumulating during 1877 may some, pay for accordingly. what interfere, but after that the permanently reduced Messrs. Meister, Lucius, and Brüning's methods are prices of tar will enable him to supply genuine anthracene not for ascertaining the exact quantity of pure anthracene at paying prices.

in crude anthracene, but for ascertaining pure anthraIt is well known that true, pure anthracene passes over quinone; the latter is the direct result, whereas the former at a certain limited stage of the distillation, and this pro- is a calculation therefrom. duct only was originally sold: the suddenly increased I shall hereafter go more fully into the question as to demand for large quantities induced the distiller to sepa- the value of Messrs. Meister, Lucius, and Brüning's prorate as much solid hydrocarbons as possible, and thus the posed treatment of quinone with sulphuric acid, my exquality of anthracene deteriorated to such a degree that periments not having led me, up to the present, to a any article tested by alcohol, and showing a melting-point final conclusion, but this I can say, that the calculation of of 190° C., was sold as anthracene. The increasing im- found quinone into anthracene is quite unnecessary, and purity of the merchandise called forth improved methods this practice ought to be abolished. The price per unit of of analysis, until at last the chemist is obliged to demon. quinone will soon find its level in the natural course of strate, by more delicate tests, that most of the anthracene trade. at present in the market is of a very doubtful character. With regard to Dr. Versmann's interesting Reports on

I think the tar distiller may well bear this in mind, be- his separation of crystals from powder, which at the first cause upon the good quality of anthracene to a great reading of his elaborate experiments on various samples extent depends the future existence of the alizarine manu- seems to be a valuable improvement on the hitherto facturers, and the more flourishing these the better will be adopted mode of testing, the same will, after carefully the prices of anthracene.

examination be found impracticable and unreliable. 35, Whitecross Place, Wilson Street,

It is only fair for me to state that, as a personal friend Finsbury, E.C.

of the Doctor's, I had, about four months ago, the advantage of being confidentially acquainted by him of his above mode of testing, and that since I have had an opportunity

of completing a series of experiments in a similar way as ON ANTHRACENE TESTING.

described by him, but with quite different results ; yet I

can scarcely object to the Doctor's very cautious and By C. CASPERS.

reserved remark about the value of his method, viz., that

it “may tend to throw some light on the nature of the In consequence of the publication of Messrs. Meister, products obtained.My intention is merely to state some Lucius, and Brüning's, "New Method for Ascertaining of my results as compared with his own. the Exact Quantity of Pure Anthracene Contained in Dr. Versmann puts great importance on the ascertaining Crude Anthracene," and by Dr. Frederick Versmann's of the melting points of his products, based upon the subsequent Report on his treatment of crude samples principle that pure quinone melts at 273° C., but he “in a different direction," I am induced to publish my seems to have lost sight of his own most contradictory views on the above subject, which may be interesting to results in that respect. I refer to his Report about the science and the trade in general.

“ Effect of Purifying Two Samples of Anthracene by Two The analysis of crude anthracene, since this article Consecutive Treatments” (Chemical News, vol. xxxiv., became of commercial importance, has undergone various p. 193) in which he finds the powder of the "í. Original" remarkable alterations, and certainly great improvements. not to melt at 300° C.; first treatment, mean, 265°, C.; The alcohol and bisulphide of carbon tests were simply and second treatment, not at 300° C. again. The intended to give a guidance as to the insoluble portion in " 2. Original” does not melt at 300° C.; first treatment a certain quantity of mixed hydrocarbons contained in the at 270° C.; second treatment, not at 300° C. What can last runnings of coal-tar distillates, and are now entirely prove more the instability of the melting-point ? out of practice through their unsatisfactory results, though I now may be allowed to state the results of my tests checked by a stipulated melting-point of the residue. carried on in a similar manner to Dr. Versmann's sugges

The so-called " Meister, Lucius, and Brüning's Anthra- tion. I have separated a number of crystals from the quinone Test," is based upon the action of certain oxidis- powder previous to the addition of water to the acetic ing agents upon anthracene (C14H10) only, and at the acid, and never could find more nor less than about same time upon the destruction of all other hydrocarbons 0'038 grm., which I can only explain in this way: that mixed with it. The obtained residue, treated with a hot 55 c.c. of glacial acetic acid always keep this quantity in solution of dilute caustic-with or without the appendix solution, and precipitate it in the form of powder after the -is supposed to be a pure oxidised compound of anthra- addition of sufficient water. If, say, o'10 grm, of this

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