NEWS nearly as much bitumen as cannel coal.] This is a general statement, such as you find in chemical works generally. There are different qualities of coal which yield different quantities of oil. I have heard of M. Selligue's process. [The account of it is given in the Jury Report on the exhibition of French industrial products in 1839. The oil is distilled from schist, and on redistilling the crude oils, they are separated into a drying oil, an oil suitable for burning in special lamps, a bituminous residue, a lubricating substance, and lastly, paraffine.] I saw candles made by Selligue in the London Exhibition of 1851. The substances obtained by Selligue, with the exception of the paraffine, are so ill defined that I could give no opinion upon them. The crude oil, from which the drying and the burning oil, &c., are obtained, would probably be produced from schist at the range of temperature described by Mr. Young. I have never seen the French schist, but I have obtained by distilling Dorsetshire shale products, especially paraffine, which inclines me to believe that a temperature of a low red heat would probably yield analogous products. I know Lord Dundonald's specification. [It is dated 1781, "for making tar, pitch, gas, &c., from coals." The following extract from the specification will give our readers an idea of the process. It is declared that "persons who shall extract tar, pitch, essential oils, volatile alkalies, mineral acids and salts, from pit coals in vessels or buildings (it matters not their shape or size), whereby the coals are made to burn or ignite without flaming by a regulated admission of the external air through different apertures in the buildings, so as by their own heat to throw off the tar, oils, &c., that they contain; persons who do so without permission are deemed to encroach upon my patent; as the only method known or used until my new discovery was distillation of coal in close vessels, where the admission of external air was prevented."] It is evident with this patent that you must employ a high temperature, for the object is to obtain pitch and coke. There is an extension of the patent. The pitch is produced in the first operation, but is obtained in a subsequent process by the separation of the more volatile from the less volatile products. I have said that the great principle of Mr. Young's invention is the use of a graduated and moderate temperature and the selection of proper coal. ["Ure's Dictionary," edition 1821, was now referred to. The extract read was the following: "If coal be put into a cold retort and slowly exposed to heat its bitumen is merely volatilised in the state of condensible tar; little gas, and that of inferior illuminating power, is produced. This distillatory temperature may be esteemed at 600° or 700° F. If the retort be previously brought to a cherry-red heat, then the coals, the instant after their introduction, yield a copious supply of good gas, and a moderate quantity of tarry and ammoniacal vapour."] This passage refers chiefly to the manufacture of gas, and appears to say that if the heat be very strong a gas is obtained of inferior illuminating power; and that if it be very low you obtain little or no gas, but substances which he describes as bitumen or condensible tar. He states the temperature to be 600° or 700° F. I do not believe the coals Mr. Young employs in his operations give off any bitumen or condensible tar at 600° or 700° F. If this bitumen is given off at 600° or 700° F., the kind of coal used must be essentially different from that Mr. Young employs. Dr. Ure speaks of gas coal, but of a kind of coal which yields volatile matter at 600° or 700° F. I think there is some discrepancy in the temperature. I gave the range of temperature [of a low red heat] from 800° to 1000°, but one man may take it as little more than 800° and another near to 1000°. The general belief now is that it is nearer to 1000° than 800°. Dr. Ure, in his book, gave it as 812. [The next extract referred to was from a paper by Dr. Henry in the "Annals of Philosophy," 1819. It was as follows :-" The temperature to which coal is subjected must necessarily be a point of the greatest importance to the quantity and quality of the aeriform products; for, while too low a point distils over, in the form of a condensible fluid, the bituminous part of the coal which ought to afford gas, too high a temperature, on the contrary, occasions the production of a large relative proportion of the lighter and low combustible gases. With the view of ascertaining how low a degree of heat is adequate to the production of gas from coal, I placed a small iron retort about the fusing-point of lead a dull red or bloodcoloured heat. This temperature I suspect is rather too low, and has a tendency to distil over too much tar."] This statement appears incompatible. The author speaks of the fusing-point of lead, and calls it a dull red or blood-coloured heat. At about the fusing point of lead you could not possibly obtain a dull red or blood-coloured heat. [It is right to say that the extract, as read by the Attotney-General, is garbled. Dr. Henry does not speak of the fusing of lead as a dull red or blood-coloured heat. It was a separate experiment, in which a Wedgwood pyrometer was used to indicate the temperature]. Dumas' Chemistry Applied to the Arts" (1828) was next quoted. "Coal exposed to a bright red heat in a close retort is rapidly decomposed, yielding coke, tar or oil, water and gas. The relative quantities of each of these substances differ not only according to the varieties of the coal, but of the temperature. Experience has shown that the quantity of oil or tar, as well as that of coke, is greater when the temperature is low. The proportion of gas, on the contrary, is greater at a high temperature; that is to say, more gas is obtained the less oil is produced. In making illuminating gas, the retorts are in the first place brought to a cherry-red heat."] In this passage there is a general statement of the necessity, in the manufacture of gas, of a high temperature. Cherry-red, I would say, is a good red-a bright red heat. [Kane's "Elements of Chemistry" (1841) was next quoted from. The author having mentioned fossil wax and rock oil, &c., proceeds :-"The products of the distillation of coal in close vessels possess a remarkable analogy to those that have been now described. The liquid products consist of various bodies closely analogous to petroleum, and the solids consist of naphthaline and paraffine. The relative proportions of these products vary with the temperature. The lower the heat employed the less gas and the more solids and liquids are produced.] The liquid products may or may not correspond to the crude oil of Mr. Young according to the nature of the coals and the temperature. Kane says that to get those liquid products analogous to petroleum you should employ a lower heat; but it is not so with regard to solids. The temperature for naphthaline should be high, and for paraffine low. Re-examined by Mr. Bovill: We need not give the reexamination at great length. The papers of Reichenbach were first referred to, and in answer to the question whether these papers are of any practical value in pro. curing paraffine as a commercial article, Dr. Hofmann stated that the papers were essentially of a scientific nature. Reichenbach certainly had a commercial article in view, but he did not get it; Mr. Young did succeed. The statement that paraffine is a product of the carbonisation of all organic substances is a mistranslation. The correct translation is that paraffine is a product of the carbonisation of animal tar, vegetable tar, and pit coal tar. Reichenbach's experiments on the distillation of coal were laboratory experiments. He states that he always obtained eupion, picamar, creosote, paraffine, moder, sulphur, &c. I have never seen picamar; I cannot say whether it is present in Mr. Young's oils; I do not think that moder or sulphur is present; I do not know whether creosote is present or not. Eupion may or may not be present; but the properties of eupion given by Reichenbach do not correspond with those belonging to Mr. Young's oil. With regard to the various specifications referred to in the cross at 212°, and alcohol at 172°. But mixtures of water and alcohol boil at intermediate temperatures. Now, paraffine oil is a mixture of substances boiling between 300* and 500°. These substances have been examined, and several individuals have been isolated, which undoubtedly have the same composition as olefiant gas. But some have been found which contain a less quantity of carbon than olefiant gas; so it is impossible to say that the oils have the same composition as olefiant gas. An experiment of Sir B. Brodie will clucidate the question. He took a bent tube, introduced some paraffine, and then sealed the open end. He thus had a glass tube containing paraffine, closed at both ends. He then applied heat to the paraffine until it passed to the other end of the tube, and afterwards distilled it back again. After two distillations he found that the paraffine would no longer solidify, and after distilling it six or seven times the tube burst from the production of gas. The liquid portion no longer contained a trace of solid paraffine, but was found to consist of an oily substance boiling between 300° and 5c0°. So that to my mind Sir B. Brodie has succeeded in converting paraffine into paraffine oil, and at the same time into olefiant gas, which was obviously the cause of the explosion. The other subjects upon which Dr. Hofmann was examined will be better understood from the evidence of subsequent witnesses. We have necessarily given Dr. Hofmann's evidence at some length. With the other witnesses for the plaintiff we shall only give such evidence as may be contradictory, or in which new matters are introduced. examination, not one informs the public how they could practically make paraffine for commercial purposes from bituminous coal, or discloses Mr. Young's process. Nothing that had been done with shale would enable a person to know with certainty that he could produce a similar effect with bituminous coals without experiments. Mr. Young's general description of coals would be well understood. Boghead would, according to my belief, be properly called a cannel coal. Coal is not a definite chemical compound; it is difficult to trace the line of demarcation between coal and stone. I could not tell the properties of a coal from mere inspection or by scratching with a knife. I could not do so at all without I had an opportunity of making a chemical examination of it. I never heard boghead cannel called schist until the trial of Gillespie v. Russell. [The celebrated Torbane-hill mineral case. The question whether boghead was a coal or a schist was not decided at the trial. The scientific evidence was pretty equally balanced on the question.] In my judgment boghead mineral is a different thing from shale. I distilled shale, to ascertain whether similar results could be obtained from it, in 1857. I obtained very little paraffine from it, and the oils had a nauseous odour; they had to be submitted to a succession of chemical operations to deprive them of their odour. In Genssane's process, described by Morand, coals are said to lose one-eighth of their weight, in Mr. Young's process as much as 50 per cent. is volatilised. According to my belief, Genssane's plan is not a practical mode of making Mr. Young's oil. A great deal of the oil if it were produced would he lost, being carried off by the perpendicular tube which communicates with the atmosphere, The judgment in this important case is being delivered and which is placed just at the point where the products as we go to press, and we shall give it next week. On emerge from the furnace. Du Buisson's is a process of announcing his intention to deliver his judgment, the distillation like Mr. Young's, but he makes use of bitu- learned Vice-Chancellor remarked that the case had minous schistus, clay slate, &c. The heat employed, it given him great labour out of Court, which he would not is said, must not exceed a cherry red, which is very dif- regret if it had advanced the administration of justice one ferent to a low red heat. The materials differ, and the whit. But the fact was, that nineteen-twentieths of the process differs from Mr. Young's. Du Buisson states of evidence was foreign to the case, and only increased the his oil that it saponifies very well, and appears to derive a expense, and delay and loss of time to the public. After great part of its properties from the presence of paraffine. perusing much of the evidence, we quite agree with the Mr. Young's oil will not saponify. I have never made Vice-Chancellor, that the greatest part was foreign to the the experiment, but I know from the nature of the sub-case; but as some points of general interest to chemists stances that it will not. Du Buisson's statement that and to manufacturers were introduced, we shall continue paraffine is contained in the largest proportion in schistus our abridgements. would mislead a person with respect to bituminous coals. Experiments would refute Du Buisson's opinion. No person from reading his specification would be aware that paraffine could be obtained from bituminous coals. [A question was here asked about the composition of paraffine and paraffine oil, and at the request of the Vice-Chancellor, Dr. Hofmann went into the chemistry of the matter. We give an abridgment of his statement.] When paraffine was first examined, it was said to have the same composition as olefiant gas, but this was subsequently denied by Lewy, who stated that he found for one part of hydrogen 5'95 parts of carbon. The subject was pursued in this country by Professor Anderson, Sir Benjamin Brodie, and others. Professor Anderson examined two varieties of paraffine, one from Boghead cannel and another from Rangoon tar. Lewy's experiments were made with paraffine obtained by the distillation of wax. Professor Anderson found that paraffine is not an individual compound, but a mixture of several compounds. Amongst these he admits the existence of one having the same composition as olefiant gas, and another having the composition given by Lewy; he adds that there are probably several in which one part of hydrogen is contained with 5'95—5'96 of carbon. Sir B. Brodie's experiments led him to the conclusion that paraffine had the same composition as olefiant gas, and I believe he is correct. The liquids are not a pure chemical substance, but a mixture of substances. In fact, paraffine oil boils between 300° and [500°. A pure chemical substance boils at a fixed temperature. Water, for instance, boils (To be continued.) The Medical Council and Pharmacy.-At the last meeting of the Council the following resolution was moved by Dr. Corrigan, seconded by Dr. Quain, and agreed to:-"That a communication be addressed to the Secretary of State for the Home Department, drawing his attention to the present defective state of the law regarding the practice of pharmacy, under which any person, however ignorant, may undertake it; and expressing the opinion of the General Medical Council that some legislative enactment is urgently called for to insure competency in persons keeping open shops for dispensing medicines and for the compounding of physicians' and surgeons' prescriptions." ANSWERS TO CORRESPONDENTS. Mr. Newland.-Received with thanks. The cause of the error will be inquired into. Mr. W. Sydney Gibbons.-Received, with thanks. A Manufacturer.-We have answered your question many times. The Commissioners will not sell the Chemical Report separate from the others, cult matter. G. W.-The estimation of small quantities of starch is a very diffiThe process you mention is, perhaps, the best for the purpose. It will be necessary to boil for some time; a very little acid will suffice. We have also to correct a slight error in the percentage calculation of Errata.-Page 240, column 1, for carbonic acid read carbonic oxide. the water in thallium-iron alum, p. 205. In place of 33 147, it should be 32:029. S. T. B. will see the correction above. Book Received.-"Class Book of Rudimentary Chemistry." By the Rev. Geo. Pope, M.A. SCIENTIFIC AND ANALYTICAL CHEMISTRY. A New Method of Producing Aldehydes, THE different processes for preparing aldehydes consist 1st. The oxidation of alcohols. 2nd. The oxidation of nitrogenised matters, such as albumen, gelatine, &c. 3rd. The dry distillation of salts from fatty acids. 4th. The same distillation conducted with that of the formiates of lime and baryta. 5th. The distillation of albuminoid substances. 6th. The dehydration of glycols. On the strength of several observations, the author thinks himself justified in laying it down as a general fact that an aldehyde is always to be obtained by submitting an ammoniacal base to a proper oxidation. Among them is the acetic aldehyde CHO, rapidly developed when ethylamine is poured on crystallised permanganate of potash. At first violet, the liquid turns green, developes heat on shaking, becomes brown with effervescence, and finally evolves the aldehyde, so perceptible by its odour. The gas of the reaction passed into an ammoniacal solution of silver, promptly reduces it, forming a metallic silver mirror. With methylamine he has obtained a strongly reducing gaseous compound like the above, and, like it, capable of forming a crystalline compound with ammonia. He has not analysed it, but believes it to be the hitherto unfound aldehyde of methyle. With trimethylamine a compound is produced which the author believes to be identical or isomerio with propylamine.-Journal de Pharm. et de Chemie, xlv., 100. 64. A New Quadruple Salt, by M. PELTZER. By treating sulphate or acetate of copper by hyposulphite of soda there results, as is well known, a double sulphite, which has been studied by M. Lenz and M. Rammelsberg. This hyposulphite is soluble in ammonia, to which it imparts a blue colour, and when left to itself the solution deposits a mass of blue crystals which constitute the new salt. It may be obtained still more easily in the following manner :-Divide into two equal parts a mixture of sulphate of copper; supersaturate one with ammonia and the other with hyposulphite of soda, and mix the two solutions; by shaking the mixture, the new product is deposited in a crystalline mass of a beautiful violet colour. The latter gives out a decided ammoniacal odour, especially if reduced to powder; it will bear a temperature of 100° C. Heated in a tube it loses no water, but forms a white sublimate which becomes orange by cooling. When boiled with water this sublimate emits ammonia, and on the addition of hydrochloric acid there follows a disengagement of sulphurous gas, which shows the sublimated product to contain M. H. Rose's sulphate ammon. Mixed with chlorate of potash, it detonates with some violence. Water, especially when hot, decomposes but does not dissolve it; a green matter and white flakes of a salt of protoxide of copper are formed, and ammonia is disengaged; by prolonged boiling sulphide of copper is formed. VOL. IX. No. 235.-JUNE 4, 1864. The new salt is soluble in ammonia, hyposulphite of soda, and acetic acid. Heated with potash it deposits at the boiling point a mixture formed of protoxide and deutoxide of copper. The solar rays decompose the acetic solution, hypochlorite of soda also destroys it, forming a white precipitate containing protoxide of copper and tetrathionic acid. Nitrate of silver produces a white precipitate; the precipitate, however, soon disappears to give place to a green deposit soluble in ammonia, but easily giving a deposit of sulphide of silver. The deposit contains copper, silver, and hyposulphurous acid. The author is of opinion that iron, zinc, and silver may be substituted for copper; besides, ferruginous sulphate of copper gives a quadruple salt containing iron. The author has found for the percentage composition of this salt— Cu302 NH3 thence he deduces the formula— 27.76 15'52 8.52 48.19 S2O2Cu2O,S2O2CuO + 2 (S2O2NaO) + 2AzH ̧*. According to him ammonia here plays only a passive part, acting in the same way as water of crystallisation. -Journal de Pharmacie et de Chemie, xlv., 101. 64. TECHNICAL CHEMISTRY. The Formation of Aniline Yellow.-Researches on Aniline Yellow.-This matter, which M. Schiff has often produced in the course of his researches on aniline. colours, is, according to him, easily prepared by means of hydrated antimonic or stannic acid. The alkaline antimoniate or stannate is pounded with bouillie, then hydrochloric acid is added till the acid rehalf its weight of aniline, to the consistence of a clear action takes place. It is then shaken up, and the scarlet colour removed by etherised alcohol, the mass being, of course, previously dried. After proper purification it is allowed to evaporate spontaneously, and in this way are formed flakes of a hydrochlorate, having for base a red rosaniline. colouring matter, which must not be confounded with deep yellow flakes are deposited, which again become When this hydrochlorate is decomposed by alkalics, red in presence of acids. and then passing it into a hot solution of carbonate of By impregnating silk or wool with this red colour, soda, a beautiful yellow tint is developed, similar to the yellow of picric acid, and which the author believes to possess considerable stability. Aniline yellow, then, may be developed on the stuff itself, by first producing the red above described, which, as has been shown, may easily be done by means of the stannate of soda so much used in dyeing. The author has not yet decided on the composition of these colouring matters, but intends making them the subject of a future communication.-Journ. de Pharm. et de Chem., xlv., 110, 1864. *This empirical formula may be decomposed into S2O2Cu2O.S2O2NaO+S2O2 CuO,S2O2NaO+2AzH3. which gives a quadruple salt differing from those already known only in containing three different bases and one acid. PHYSICAL SCIENCE. platinum. The copper, iron, and zinc dissolved quickly; some of the gas evolved by the zinc exploded. Large crystals of iodine which had long been exposed On the Electrical Relations of Metals, &c., in Fused in a bottle near lumps of fused chloride of calcium, gave, Substances, by GEORGE GORE, Esq. IN the following experiments most of the substances to be fused were contained in small porcelain crucibles, and heated by means of the flame of a Bunsen's burner; the more infusible bodies were melted in clay crucibles in one of my small gas furnaces, particular care being taken to have neither an excess of gas nor of air in the furnace, by testing at the top of the chimney for carbonic oxide by means of a brightly red hot rod of iron, and diminishing the supply of gas until all traces of carbonic oxide precisely disappeared. The condition of the contents of the crucible could at all times be ascertained without admit ting air into the furnace by placing upon the top of the furnace a vertical tube of fireclay about four inches high closed at its upper end by a thin disc of glass. The materials of which the electrodes were composed included carbon, magnesium, aluminium, silicium, zinc, tin, lead, iron, nickel, copper, silver, gold, and platinum. The carbon consisted of bars of gas-graphite as used for electric lamps; the magnesium was a rod of Mr. Sonstadt's purest variety; the aluminium was obtained from Messrs. Bell, of Newcastle; the silicium was in the form of lumps obtained by fusing the finest crystals under a mixture of powdered Bohemian glass, silico-fluoride of potassium, and a little hydrate of potash; the zinc, tin, and lead were of the best commercial kinds; the iron was "pianoforte wire;" the rod of nickel was kindly given to me by Mr. H. Wiggin, of the firm of Evans and Askin, Birmingham; the copper was ordinary wire of commerce; the silver and gold were of "virgin" quality; and the platinum was obtained from Messrs. Johnson and Matthey, London. The most superficial consideration of the conditions of these experiments will show that a number of interfering circumstances were more or less necessarily present, and that the results obtained are not in all cases simply and purely due to chemicoelectric action; for instance- 1. thermo-electric action of the heated and immersed ends of the electrodes; 2. Ditto of the ends of the electrodes out of the fused substance, which in many cases could not be removed a sufficient distance to be out of the influence of the heat; 3. The chemical influence of infusible or insoluble films formed upon the immersed electrodes; 4. The accumulation of liquid of different composition around the electrodes; 5. Evolution of gases at the electrodes; 6. Alteration of structure of the electrodes by heat, their semifusion, etc.; 7. Currents occurring when by the relative coldness of the electrodes the fused salt around them solidified; and 8. In addition to all these, the interference of impurities in the fused substances and in the electrodes themselves. It will at once be seen that some of these interferences could not be prevented or avoided; with regard to the others every reasonable precaution was taken, and the results in each uncertain case properly verified. In the following lists the most positive substance is in each case named first, and substances united by the mark were about equally positive: With fused boracic acid the following order of electrical relations was found: Iron, silicium-carbon, platinum, gold, copper, silver. The currents obtained were very feeble. Glacial phosphoric acid: Zinc, iron, copper, silver, when fused, feeble currents with silver and platinum, the former being positive. Fused selenium yielded no currents with platinum and copper or silver. Sulphate of ammonia: Zinc, copper, silver, iron, platinum, carbon. Copper evolved much gas, and dissolved violently. silver, tin, aluminium, iron, silicium-carbon, platinum. Nitrate of ammonia: Magnesium, zinc, lead, copper, Lead was very strongly positive to copper without manifesting strong chemical action. Zinc evolved gas violently. lead (?), carbon, copper, platinum, silver. Silicium was Hydrate of potash : Silicium, aluminium, zinc, iron, strongly positive to aluminium, and strongly acted upon with evolution of gas. The results were variable with copper and platinum, and with platinum and silver. Borate of potash: Iron, zinc, copper, silver, platinum. Phosphate of potash: Zinc, iron, copper, silver, platinum. Sulphide of potassium: Aluminium, zinc, copper, silver, platinum, carbon, iron. Copper and silver dissolved rapidly with violent action. Reversals of current occurred with platinum and aluminium, silver and aluminium, aluminium and zinc, iron and platinum, iron and carbon, silver and copper. Iodide of potassium: Aluminium, zinc, iron, silver, copper, platinum. Reversals of current with copper and silver, copper and platinum, iron and zinc, probably from salt solidifying round the electrodes and subsequently fusing. Bromide of potassium: Zinc, iron, copper, silver, platinum. Reversal of current with iron and zinc. Chloride of potassium: Aluminium, zinc, iron, copper, silver, platinum. Reversals with silver and platinum, silver and copper, silver and iron, iron and copper, iron and zinc. Chlorate of potash: Zinc, aluminium-iron, silver, copper, platinum. The currents were feeble; they were also indefinite until gas was evolved. Nitrite of potash: Aluminium, zinc, copper, silver, iron, platinum. iron, zinc, platinum, silver. Nitrate of potash: Tin, lead, aluminium, carbon, copper, versals with iron and platinum, iron and silver, carbon Currents very feeble. Reand copper. Carbon evolved much gas. platinum. Reversals with silver and platinum, copper Hydrate of soda: Zinc, iron, carbon, copper, silver, and iron, carbon and iron. Moving either platinum or silver made each more positive. Biborate of soda: Zinc, carbon, iron, copper, silver, platinum. Iron and zinc evolved gas. Mono-pyrophosphate of soda: Iron, copper, silver, carbon, platinum. Reversal with silver and carbon. Sulphide of sodium: Zinc, copper, silver, iron, platinum, carbon. Reversals with iron and carbon, iron and platinum, iron and silver. Iron much dissolved. Hyposulphite of soda (aqueous fusion): Zinc, carbon, copper, silver, iron, platinum. Bisulphate of soda (aqueous fusion): Iron,, copper, silver, carbon, platinum. Reversal with iron and platinum. Gas evolved by iron. Iodide of sodium: Iron, silver, copper, carbon, platinum. Reversals with platinum and silver, platinum and CHEMICAL NEWS, Electrical Relations of Metals, &c., in Fused Substances. copper, platinum and carbon, carbon and copper, copper and silver, copper and iron, silver and iron. Bromide of sodium: Zinc, iron, copper, silver, platinum. Reversals with platinum and silver, iron and zinc. Chloride of sodium: Iron, copper, carbon, silver, gold, platinum. Reversals with carbon and copper, carbon and iron. Nitrate of soda: Aluminium, zinc, carbon, copper, silver, iron, platinum. Reversals with silver and iron, carbon and copper, iron and copper. Carbon evolved much gas. Microcosmic salt, aqueous fusion: Zinc, iron, silver, copper-platinum, carbon. A mixture of carbonates of potash and soda: Silicium, iron, zinc, carbon, copper, silver, platinum. Reversals with platinum and silver, silver and copper, copper and carbon. Silicium was strongly positive to iron, and much action and gas at the surface of silicium. A mixture of fluorides of potassium and sodium: Silicium, iron, carbon, copper, silver, platinum. Electric currents strong. Silicium rapidly acted upon and dissolved, and evolved much gas. Carbonate of lithia: Iron, carbon, copper, silver, platinum. Reversals with platinum and silver, copper and carbon. Much effervescence. Iodide of barium: Iron, carbon, silver-copper, platinum. Reversal with copper and silver; either was positive when moved. Silver freely dissolved. Bromide of barium: Iron, carbon, copper, silver, platinum. Reversals with silver and copper, copper and iron, carbon and iron. Nitrate of baryta: Zinc, carbon, copper, silver, iron, platinum. Reversal with copper and silver. Carbon evolved much gas, which appeared to make it negative to copper, and to silver especially. Iron evolved much gas. A mixture of caustic baryta and the fluorides of potassium and sodium: Silicium, iron, carbon, copper, silver, platinum. Carbon evolved gas, iron much gas, and silicium very much gas. Nitrate of strontia: Carbon, platinum, iron. Reversal with iron and platinum. Iodide of calcium, aqueous fusion: Silver positive to platinum. Bromide of calcium, aqueous fusion: Zinc, copper, iron, platinum. Nitrate of lime: Silver, copper, platinum, iron, carbon. Nitrate of magnesia, aqueous fusion: Zinc, silver, iron, silicium, carbon, platinum. Silicate of potash (water glass): Copper, silver, platinum. Bohemian glass: Carbon positive to iron. Current feeble. A mixture of fine white sand and hydrate of potash: Nickel positive to carbon. Silico-fluoride of potassium: Silicium, iron, carbon, copper, silver, platinum. Iron and silicium evolved gas. A mixture of soda-lime, white sand, and hydrate of soda: Carbon strongly positive to nickel. Tungstate of soda: Aluminium, iron, copper, silicium, carbon, silver, gold, platinum. Reversal with gold and carbon. Molybdic acid: Copper, silver, platinum, carbon. Silver and copper acted upon. Bichromate of potash: Silver, copper, silicium, carbon, iron, platinum, gold. Reversal with copper and silver. Chromate of soda: Iron, copper, carbon, silver, platinum, gold. Currents strong. Chloride of manganese: Copper, silver, iron, carbon, gold, platinum. Currents strong. 267 Bisulphide of arsenic: Silver, iron, carbon. Silver dissolved rapidly. Tersulphide of arsenic: Copper, iron, platinum. Teriodide of arsenic: Silver positive to platinum. Bad conductor. Arsenite of soda: Iron, silicium, carbon, silver, copper, platinum. Reversals with silver and carbon. Iron, silicium, and carbon evolved much gas. Platinum, copper, and silver rapidly melted in it. Teroxide of antimony: Silicium, iron, carbon, copper -silver, platinum. Reversal with silver and copper. Tersulphide of antimony: Silver, copper, zinc, iron, silicium, platinum, carbon. Reversals with platinum and iron, copper and silver. Copper and silver dissolved quickly. Teriodide of antimony: Silver, zinc, copper, iron, carbon, platinum. Currents feeble. Terbromide of antimony: Copper, silver, zinc, iron, platinum, carbon. Reversal with zinc and iron. Currents very feeble. Oxybromide of antimony: Silicium, iron, copper, silver, carbon, platinum, gold. Silver and copper dissolved quickly.. Fluoride of antimony: Zinc, iron, copper, silver, carbon, platinum. Iron coated itself black. Bromide of zinc: Copper, iron, silver, platinum. Chloride of cadmium: Aluminium, zinc, iron, copper, silver, platinum. Reversal with silver and copper. Zinc melted quickly; aluminium similar, with violent action. Mineral phosphate of lead: Iron positive to carbon. Strong action upon iron, and iron dissolved; gas also evolved from carbon. Much lead reduced to a metallic button. Iodide of lead: Zinc, silver, copper, iron, platinum. Reversals with platinum and iron, silver and zinc. Copper and silver dissolved rapidly. Chloride of lead: Zinc, lead, copper, iron, silver, platinum. Reversals with copper and silver, copper and iron. Chromate of lead: Carbon positive to iron. Strong action and intense heat at surface of iron. Iron much dissolved; carbon also corroded. Black scale oxide of iron mixed with silica: Iron, carbon, platinum. Reversal with iron and carbon. Current strong with iron and platinum. Iron dissolved. Black oxide of copper: Platinum positive to iron as long as the iron was enveloped by an unfused coating of oxide of copper, then violent action upon the iron, attended by evolution of intense heat and very rapid solution of the iron, the iron becoming, at the same time, strongly positive to platinum. A large button of reduced copper was formed. Protoxide of copper appears to evolve oxygen gas when fused. The following inferences may be deduced from these experiments : The most negative substances in fused salts are generally platinum, gold, carbon, and silver; the most positive substances are generally magnesium, aluminium, and zinc. Silicium is generally electro-positive to carbon, and is strongly positive and quickly corroded in fused alkalies, alkaline carbonates, or fluorides. Carbon is not generally very positive to iron. The following facts may also be noticed: Copper and silver dissolve rapidly in fused sulphide of potaasium, tersulphide of antimony, or iodide of lead; silver also dissolves freely in iodide of barium and bisulphide of arsenic. Platinum, copper, and silver rapidly melt in fused arsenite of soda. Electric currents were |