CHEMICAL NEWS, Science Scholarships. 207 nington Road. Managing Director, DR. MUTER. Daily Lectures on the following subjects: CHEMISTRY. MATERIA MEDICA. The School has accommodation for 120 Students, and contains an excellent Museum and a very completely fitted Chemical Laboratory for 50 Junior and 20 Senior Pupils, with water and gas at every working The students at this college have, he says, never yet been South London School of Pharmacy, 325, Kenequalled at the London University examinations by the students from any of the other colleges in the United Kingdom. They have hitherto invariablyobtained honours in chemistry. In 1870 a University Exhibition was established. It was not awarded in the first two years. The College of Science gained it both in the fifth and seventh years. No other institution has taken it twice, and it has only been gained once by three others-viz., Guy's Hospital, University College, and the School of Mines. The competition for honours is very severe. Sixty students went in this, the seventh, year of the exhibition, and only ten passed, and two of such were students, and the only students, from the College of Science. bench. For all particulars, enclose a stamped envelope to the Secretary, Mr. W. BAXTER, at his office, Central Public Laboratory, Kennington Cross, London, S.E. BERNERS COLLEGE of CHEMISTRY, in conjunction with the SCIENTIFIC DEPARTMENT of the ROYAL POLYTECHNIC INSTITUTION. Instruction and preparation in CHEMISTRY and the EXPERIMENTAL SCIENCES under the direction of Professor E. V. GARDNER, F.A.S., M.S.A. The Class Rooms are open from 11 to 5 a.m. and from 7 to 10 p.m. daily. Especial facilities for persons preparing for Government and other examinations. Private Pupils will find every convenience. Analyses, Assays, and Practical Investigations connected with Patents, &c., conducted. Prospectuses and full particulars on application to Prof. Gardner at Berner's College, 44, Berners-street, W., or at the Royal Polytechnic Institution. MORRIS TANNENBAUM, 37, FITZROY STREET, offers Jewellers, Mineralogists, Lapidaries, and specially Collectors of Rare Cut Gems (which he possesses in all existing kinds), large Collections of Fine Hyacinths in all Colours Clear Spanish Topazes, Blue and Yellow Amethysts, Jargon Olivine, Fossils, Fine Collections of Shells, Thousands of Indian Pebbles. Polished Agates, &c., Starstones and Catseyes, Garnets, Cape Rubies, Fine Slabs of Lapis Lazuli, Fine Emeralds in the Matrix, Fine Crystallised Rubies and Brazilian Topazes, and effected to all parts of the world. Thousands of Rare Opals. Specimens and for Cuttings. Orders PATENTS.-Mr. Vaughan, F.C.S., British Foreign, and Colonial PATENT AGENT. Special attention given to Inventions relating to Chemistry, Mining, and Metallurgy. Guide to Inventors" Free by Post.-Offices, 67, Chancery Lane, London, W.C., and 8, Houndgate, Darlington. INDIA-RUBBER SPECIALLY PREPARED FOR CHEMICAL PURPOSES. Boots, Gloves, Gauntlets, Aprons, Pure Tube and J. G. INGRAM & SON, Ryall's Chemical Black Lead (Registered) creates no waste or dust by its magnetic adherence to the stove, and the cleanliness of application makes this one of the marvels of household economy.-Sold by all respectable grocers and oilmen in blocks Id., 2d., 4d., and is. boxes. Works, 94, Little Compton Street, Soho, London. Chemical Technology, or Chemistry in its Applications to the Arts and Manufactures. By THOMAS RICHARDSON and HENRY WATTS. Second Edition, illustrated with numerous Wood Engravings. Vol. I., Parts 1 and 2, price 36s., with more than 400 Illustrations. Nature and Properties of Fuel: Secondary Products obtained from Fuel: Production of Light: Secondary Products of the Gas Manufacture. Vol. I., Part 3, price 335., with more than 300 Illustrations. Vol. I., Part 4, price 218., 300 Illustrations. 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. NOVEMBER 6TH, 1876. S. A. SADLER, Apply to MR. T. F. SALMON, the Manager, CLEVELAND CHEMICAL WORKS, MIDDLESBROUGH; Newfall Tar Works, Carlton; and Ammonia Works, Stockton-on-Tees. Manufacturer of Benzole, Toluole, Xylol, HOLMER, near HEREFORD. ESTABLISHED 1798. ROBERT DAGLISH & CO., BOILER MAKERS, ENGINEERS, AND MILL-WRIGHTS, 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. S.A. S. is always a buyer of Coal-Tar Naphthas, Crude Anthracene and all Tar Products. All communications to be addressed to the offices at Middlesbrough. Makers of every description of Chemical, Colliery, Copper Ore, Gold 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 Agitators, Compressors for Collieries, and Weldon's Patent Chlorine Process. Caustic, Chlorate, Decomposing, and Oxalic Pans. Gas Producers for Heating Furnaces. Pyrites Burners for Irish, Norwegian, and Spanish Ores. Photographs, and other information, supplied on receipt of Orders. JOHN GRAHAM, CHEMICAL ENGINEER, NEAR MANCHESTER. Plans, Contracts, Estimates, Specifications, and Valuations; Competent Workmen sent to all parts of the Graham's Improved Burner Pipe, a sure preventative against the Destruction of Lead in Towers and Chamber Ends, and a Perfect Remedy against any Escape of Gas. Methylated Spirits.- David Smith Kidd, Licensed Maker, Commercial Street, Shoreditch, N.E. Also FINISH, FUSEL OIL and RECT. NAPHTHA. Water-glass, or Soluble Silicates of Soda and Potash, in large or small quantities, and either solid or in solution, at ROBERT RUMNEY'S, Ardwick Chemical Works, Manchester. CHEMICAL NEWS,} Nov. 17, 1876. Repulsion Resulting from Radiation. THE CHEMICAL NEWS. VOL. XXXIV. No. 886. ON REPULSION RESULTING FROM RADIATION.-PART II.* By WILLIAM CROOKES, F.R.S., &c. 97. Two other forms of the bulb-apparatus require mentioning. A thin glass bulb was blown 2 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, bichromate 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, FIG. 5. FIG. 4. whatever was the surrounding shell of liquid. That all these liquids allowed heat to pass through was proved with a thermopile. Solution of sulphate of copper was the most opaque to heat. 98. Another form of apparatus is shown in fig. 5. Two 209 bulbs were blown one in the other, and they were fused together at the necks; to the neck a small tube was fused for connecting with the Sprengel pump. The space between the two bulbs was then perfectly exhausted, and the small tube sealed up. I thus possessed what might be called a spherical shell of vacuum surrounding a bulb open to the air. In this inner bulb was suspended a pith ball on the end of a glass arm balanced by a knob of glass on to the other end, the suspending fibre being protected by a glass tube fitting into the neck of the inner bulb with a cork. It was found that heat applied to any part of the outer bulb passed across the vacuum, and attracted the pith ball (suspended in air). The spherical shell of vacuum across which the heat passed, therefore, produced no change of action, but simply behaved like an extra thick glass bulb. This experiment bears upon the speculation in par. 81 of my former paper on this subject. 99. Having succeeded in proving the fact of repulsion resulting from radiation, I was desirous of getting some quantitative estimations of the forces under examination. A pendulum-apparatus was constructed as shown in fig. 6. A wide glass tube (a b) has fused to it a narrower tube (cd), about 40 inches long; e is a turned mass of magnesium, weighing 42 grains, suspended by a very fine platinum wire, the distance between the point of suspension and the centre of gravity of the magnesium bob being 39 139 inches, so that it forms a seconds' pendulum; f is a spiral made of platinum plate, fastened to two stout copper wires which pass through the thick plate of glass b, and thence pass to a contact-key and a battery. The plate b is cemented (83) to the end of the tube a b, which is ground flat. g is an arm fused into the upright tube for the purpose of connecting it to the glass spiral of the pump; it is contracted at h for convenience of sealing off. The fine platinum wire is fastened at its upper end to a thick wire which is sealed into the glass, and passes through to the outside for electrical purposes (120). The distance between the pendulum bob and the spiral is 7 millims. To ignite the spiral the current from two Grove's cells was used; this brought it to a bright red heat in air, and to a white heat in vacuum. Three feet from the pendulum a telescope was firmly clamped to the bench; it was furnished with a micrometer eyepiece, with movable spider threads and graduated circle. The edge of the magnesium bob was brought into the same focus as the traversing cross wire. Observations were taken in the following manner:-The observer at the telescope brought the cross wire to zero, and then adjusted it to coincide with the edge of the pendulum bob. An assistant, guided by a seconds' watch, pressed the contact-key down for one second, then broke contact for a second, next made contact for the third second, and so on, alternately making and breaking contact for either 10, 20, or 40 seconds, counting the seconds aloud. At each second the swing of the pendulum increased; and the milled head of the micrometer was kept turning so as to let the cross wire keep up to the furthest point to which the pendulum vibrated. At the end of the experiment the position of the cross wire was taken and its distance from zero recorded. {CHEMICAL NEWS, to become inevitable, and that in no distant time, the serious consequences of which it may well be worth while to weigh and to consider beforehand. We all recollect the profound sensation created by the grand discovery of artificial alizarine and its manufacture on the large scale, which last commenced only five or six years ago. In recalling the sanguine expectations raised by this new industry, its present dismal position appears scarcely credible, and yet the fact stands out only too clearly that no other branch of chemical industry, inaugurated under such bright auspices, has in its results failen so short of just expectations,-nay, I might also say, has become so disastrous to nearly all persons who remained engaged in its pursuit. True the first pioneers -those who were actually at work while the first excitement was at its height-were wise enough to sell their fortunes at prices which brought them large profits. First among these stood Messrs. Gessert Brothers, who sold their at that time flourishing concern to a Company, and the English alizarine manufacture, which has since changed hands a second time. Putting aside a very few German alizarine makers, who profess to work at a profit, we have at present a disheartening list of many large undertakings who are hopelessly insolvent, or at least uncomfortably near to it. In Germany all public companies are very properly compelled by law to publish their annual balance-sheet in at least three newspapers, and such document-published only on the 10th inst., in the Cologne Gazette-by the "Chemische Industrie Actien Gesellschaft zu Elberfeld," formerly Gessert Brothers, tells its own tale in a few figures. This official document informs the shareholders that the loss of the twelve months' working, ending at Midsummer last, amounts to £40,000; and as this dismal statement is merely a repetition of previous equally unsatisfactory balance-sheets, there seems to be little doubt that at next month's general meeting the Company will be wound up, and that very likely the whole capitalamounting to some £180,000-will be lost. Again, a private firm, Messrs. Schoneberg and Hufschmidt, also of Elberfeld, recently suspended payment, with liabilities estimated at £90,000 and assets £60,000, or a deficit of £30,000. The "Stueckfärberei Gesellschaft" and the "Elberfeld Aniline and Alizarine Gesellschaft," also joint-stock companies, are defunct for some time, their capital having been entirely lost. Plain facts like these-and the list might easily be made more complete-may well lead to an inquiry into the cause of such calamity. It may be justly argued that bad management, want of skill or proper knowledge in the manufacture, and, above all, the general depression in all trades, especially in the cotton trade and everything depending upon it, have a great deal to do with the nonsuccess of so many undertakings; but I believe the real and primary cause to be the most unhealthy state of the anthracene manufacture. The fact is the production of anthracene far exceeds its demand, which, suddenly sprung up some years ago, tempted many distillers to manufacture an article of a 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. I am induced to give a few figures, which will clearly show this disproportion, and which I feel sure will be very near to the actual truth, because I have every reason to depend upon their correctne: s. Up to the end of 1877 there will be produced in England alone, including present stock, at least 1400 tons of pure or 100 per cent anthracene. The requirements of all the alizarine works at present do not exceed 2 tons a day, or 600 tons a year, of pure anthracene. The next year is expected to see a considerable increase, but if with present low prices we even double the quantity-making it 1200 tons-England alone will produce 200 tons of pure anthracene more than required. But it must not be forgotten that the Continent also supplies large quantities. The Paris Gas Company utilise their own residues, and produce, together with the other large French towns, at least 250 tons. Belgium-and more so Holland-is very active, and the production in Germany, especially in large towns, such as Berlin and Hamburg, is not inconsiderable, and even America sends her quota, if not in large quantities. Altogether there will be during 1877 an excess of many hundreds of tons of pure anthracene, and consequently low prices. The inevitable reaction will produce a reduction in the price of tar, which already shows itself in Germany. A paper there offers repeatedly, and for some time, six tar contracts without any response: the distillers bide their time, and their English brethren will soon find out, if they have not done so already, the necessity of this line of action. But-and here I come to the main point of my argument insisted upon in previous communications-the tar distiller must feel to find his advantage in the manufacture of a better and purer article. He must return to the early times of his operations, when with low tar prices a moderate price for anthracene paid him well. The large stock accumulating during 1877 may somewhat interfere, but after that the permanently reduced prices of tar will enable him to supply genuine anthracene at paying prices. It is well known that true, pure anthracene passes over at a certain limited stage of the distillation, and this product only was originally sold: the suddenly increased demand for large quantities induced the distiller to separate as much solid hydrocarbons as possible, and thus the quality of anthracene deteriorated to such a degree that any article tested by alcohol, and showing a melting-point of 190° C., was sold as anthracene. The increasing impurity of the merchandise called forth improved methods of analysis, until at last the chemist is obliged to demonstrate, by more delicate tests, that most of the anthracene at present in the market is of a very doubtful character. I think the tar distiller may well bear this in mind, because upon the good quality of anthracene to a great extent depends the future existence of the alizarine manufacturers, and the more flourishing these the better will be the prices of anthracene. 35, Whitecross Place, Wilson Street, Finsbury, E.C. ON ANTHRACENE TESTING. By C. CASPERS. IN consequence of the publication of Messrs. Meister, Lucius, and Brüning's, New Method for Ascertaining the Exact Quantity of Pure Anthracene Contained in Crude Anthracene," and by Dr. Frederick Versmann's subsequent Report on his treatment of crude samples "in a different direction," I am induced to publish my views on the above subject, which may be interesting to science and the trade in general. The analysis of crude anthracene, since this article became of commercial importance, has undergone various remarkable alterations, and certainly great improvements. The alcohol and bisulphide of carbon tests were simply intended to give a guidance as to the insoluble portion in a certain quantity of mixed hydrocarbons contained in the last runnings of coal-tar distillates, and are now entirely out of practice through their unsatisfactory results, though checked by a stipulated melting-point of the residue. 211 cene, viz., anthraquinone (C14H8O2) an intermediate and valuable article in the manufacture of artificial alizarin. It is unquestionable that the ascertaining of the portion, which, in more or less crude anthracene, undergoes an oxidation by the above method and shows itself as residue, fairly forms a guidance for the alizarine maker as to the corresponding quantity of alizarine which can be yielded therefrom, and consequently this test has a reasonable basis; but how far-chemically speaking-it may be correct is the question at issue, equally important to anthracene as to alizarine makers. Since the original anthraquinone test came into use I have always been at a loss to understand why the weight of the oxidised residue should be calculated by a certain coefficient (0.856) into "pure anthracene," and sold by the number thus obtained instead of by the original weight of the residue, because, I may say, nearly all coal-tar distillers, even those who work under the direction of efficient chemists, have unpersuadedly to believe that the specific gravities of quinone and anthracene are in proportion like 1000: 856; and also because the residue itself is the very article the alizarine maker requires and should pay for accordingly. Messrs. Meister, Lucius, and Brüning's methods are not for ascertaining the exact quantity of pure anthracene in crude anthracene, but for ascertaining pure anthraquinone; the latter is the direct result, whereas the former is a calculation therefrom. I shall hereafter go more fully into the question as to the value of Messrs. Meister, Lucius, and Brüning's proposed treatment of quinone with sulphuric acid, my experiments not having led me, up to the present, to a final conclusion, but this I can say, that the calculation of found quinone into anthracene is quite unnecessary, and this practice ought to be abolished. The price per unit of quinone will soon find its level in the natural course of trade. With regard to Dr. Versmann's interesting Reports on his separation of crystals from powder, which at the first reading of his elaborate experiments on various samples seems to be a valuable improvement on the hitherto adopted mode of testing, the same will, after carefully examination be found impracticable and unreliable. It is only fair for me to state that, as a personal friend 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 described by him, but with quite different results; yet I can scarcely object to the Doctor's very cautious and reserved remark about the value of his method, viz., that it "may tend to throw some light on the nature of the products obtained." My intention is merely to state some of my results as compared with his own. Dr. Versmann puts great importance on the ascertaining of the melting-points of his products, based upon the principle that pure quinone melts at 273° C., but he seems to have lost sight of his own most contradictory results in that respect. I refer to his Report about_the "Effect of Purifying Two Samples of Anthracene by Two Consecutive Treatments" (CHEMICAL NEWS, vol. xxxiv., p. 193) in which he finds the powder of the "1. Original" not to melt at 300° C.; first treatment, mean, 265° C.; and second treatment, not at 300° C. again. "2. Original" does not melt at 300° C.; first treatment at 270° C.; second treatment, not at 300° C. What can prove more the instability of the melting-point? The I now may be allowed to state the results of my tests carried on in a similar manner to Dr. Versmann's suggesThe 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 (C4H10) only, and at the acid, and never could find more nor less than about same time upon the destruction of all other hydrocarbons o'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'to grm, of this |