compared his own results with those of Marignac, and expresses a general concurrence with the views of the latter chemist. They agree that hyponiobic, niobous, or dianic acid is only the acid of niobium, corresponding to tantalic acid, and concur in thinking that the mineral Rose experimented with, and prepared the yellow niobic chloride from, must have contained a considerable quantity | of tantalum. Marignac regards niobium and tantalum as pentatomic metals; but Blomstrand considers them as a bi- or tetratomic. We shall probably hear a good deal of | niobium before the question is decided. M. Cailléletet presented a note "On the Gases contained in Cast Iron and Steel in a State of Fusion." As the metals run into moulds and solidify, a large quantity of gas escapes. The author has succeeded in collecting this gas and analysing it. We give the percentage composition of the gas from grey cast-iron obtained with coke :Hydrogen, 33'70; carbonic oxide, 57'90; nitrogen, 8'40. He is in doubt whether the nitrogen really escaped from the metal, or whether it was derived from air in his apparatus. We may give some account of the apparatus used, with cast-iron, at a future time. No apparatus the author could contrive would stand the experiment with cast iron, and all he can say of the gas escaping from it is, that it contained hydrogen and carbonic oxide, but the imperfection of his apparatus always admitted air. M. Gernez sent a paper "On Supersaturated Solutions." It was a reply to M. Jeannel, who attributes the sudden crystallisation of supersaturated solutions to purely physical causes. M. Gernez, our readers know, asserts that the crystallisation is brought about by the contact of a solid particle, no matter how minute, of the substance held in solution. In his present paper, M. Gernez says, at some length, that he has repeated all M. Jeannel's experiments, and has only arrived at results which confirm his own views. M. Maumené presented a note "On the Origin of the Sulphuretted Waters of the Pyrenees." The author believes he has discovered a double sulphide of iron and sodium in the slaty schist through which the water rises at Cauterets; and he makes the announcement at this moment in order that all the scientific world may take notice and stand aside while he continues the studies necessary to demonstrate that which at present he only believes to be extremely probable, viz., the existence of a double sulphide of iron and sodium in all rocks from which sulphuretted waters issue. We cannot understand upon what principle the publication of papers in the Comptes-Rendus is regulated. We find, for instance, the following:-M. Zaliwski read note "concerning a law, which, according to him, enables us to recognise à priori the solvents of iodine." The note is not published; but whatever it may have been, it could hardly have been more stupid than some that are published every week. NOTICES OF BOOKS. Chemistry and its Founders: Ferdinand Hoefer, La Chimie enseignée par la Biographie de ses Fondateurs. Paris: Hachette. 1865. To instruct, to amuse, and to furnish matter for thought -"instruire, plaire, et donner à penser "-has been Dr. Hoefer's object in writing the charming little volume before us, and among the valuable works of this distinguished author we have here one which will assuredly take a very high place. Since the appearance of Liebig's well-known Letters on Chemistry" and the late Professor Johnston's "Chemistry of Common Life" there has been no work calculated to inspire so intense a love for chemical research in the student, or to afford so much interest to the professional chemist, as the present volume. Starting from the commencement of things, Dr. Hoefer NEWS treats, in his first section, of the birth of chemistry and its gradual development through the periods of Alchymy and Pneumatic Chemistry to that of Modern Chemistry, dating from the epoch of Robert Boyle, where we get the first glimpses of chemical analysis. Around the biographical sketches of Boyle, Lavoisier, Priestley, Schéele, and Davy, in the second division of the work, are grouped those of less famed philosophers, and the discoveries of those facts upon which has been built the present colossal and useful structure of modern chemistry. In spite of the disadvantages to which science has ever been submitted in this country, compared with France and Germany, English discoveries hold a very prominent position in Dr. Hoefer's work. Indeed, since the appearance of his "Histoire de la Chimie," in two vols. (for a new edition of which chemists have long been waiting), we may safely state that this is the first time the history of chemical research has been touched upon by a truly impartial and extremely competent judge, and England will, we doubt not, be proud of the work. Schéele and Davy are, upon the whole, the finest flowers in this brilliant chemical bouquet, and the section of the book devoted to them reads with all the interest of romance. The third, and last, portion is devoted to the future of chemistry, which our author, acting up to the poet Longfellow's principles, goes forth to meet "without fear and with a manly heart.' " To assert that the origin of chemistry is lost in the "nuit des temps is, according to Dr. Hoefer, a sonorous phrase which teaches nothing. We must seek this origin in the workshops of the blacksmith, the enameller, the colour-maker, and the druggist; nay, even in the kitchens of our ancestors long before the word chemistry existed. This word, whose origin and meaning has been cause of much discussion, the author shows to date from the fourth or fifth century, and to signify the art of melting or dissolving. The birth of the process of distillation is traced back to the time of Pliny. Aristotle, who lived three centuries earlier, knew that liquids were evaporated by heat, and that their steam condensed again by cold, but Pliny gives (in his Nat. Hist., xv. 7) the first vestige of a distilling apparatus. He says, "The fire is lit under the pot which contains the resin; the vapour rises and condenses on the cloth which is spread over the orifice of the pot; when the operation is finished the cloth, impregnated with oil, is squeezed." In ancient times the art of manipulating and the art of thinking-in other terms, the artisan and the philosopher-were separated by an immense abyss; and before arriving at the state of alchemy, the science of chemistry had to wade through a very curious "sacred" period, to which Dr. Hoefer has devoted some interesting pages. This sacred or divine art was first practised by the Egyptian priests. The evaporation of water was observed to leave a sediment of earthy matter whilst the vapour rose in the air; hence it was concluded that water was transformed into earth and air. From transformation to metempsychosis there was only a step. Again, lead or tin was calcined; the oxidation which occurs signified the death of the metal. The oxide heated in its turn with grains of wheat reproduced the lead; this was the revivification or resurrection of the metal. "The grains of wheat," says Dr. Hoefer, were the symbol of resurrection or of immortality, as appear to attest the little satchels of wheat found with the Egyptian mummies." The alchemists knew, amongst other things, that copper dissolves in nitric acid, and that when a piece of iron is thrown into the solution the copper is deposited whilst the iron disappears. Let us place ourselves in the position of the alchemists in presence of this pseudo-curious fact, should we not have said, as they did, that the iron was transformed into copper? The famous theory of the transmutation of metals reposed, indeed, upon well-observed facts, but facts which were erroneously interpreted. As to the philosopher's stone, we are here NEWS space to quote from it. Born on December 19, 1742, at Stralsund, he became assistant to an apothecary at the age of 14. It was in the midst of the most obscure occupations that Schéele perfected himself in the study of a science which owes to him more discoveries than to any other man. The history of his career will encourage, for years to come, those whose first love for chemical research is attended with more than ordinary difficulties. In 1786 he married the widow who had given up to him the little pharmacy at Kjöping, which yielded him about 600 francs a year, and died two days after his marriage, at the age of not quite 44 years. The King, wishing to recompense a man whose name was so familiar to him, had his name added to the list of Swedish knights, "but his minister, little acquainted with the savants of the day," sent the order to the wrong person-some lucky homonyme. With this we must take leave, at least for the present, of Dr. Hoefer's very interesting and instructive volume. T. L. PHIPSON, Ph.D., F.C.S. again shown that the alchemists themselves varied con- | by Dr. Hoefer in a very clever manner, but we have no siderably in opinion about it. In order that his readers may judge what sort of a life an alchemist led, our author gives the history of the enthusiastic Denis Zacaire, born in 1510, who, having inherited a small fortune from his parents, was robbed, first by an Arab, then by a Greek, next by a French or a German adept, until his little income was almost entirely wasted in the vain pursuit. Zecaire tells us himself that he did, thank Heaven, finally succeed in forming gold; but whilst on his road to some place in Germany, where he was going to enjoy the fruits of his supposed discovery, the poor fellow met with a mournful end—he was assassinated at Cologne by his fellow-traveller. After a while what is called the experimental method dawned (300 years before the time of Lord Bacon *) with that extraordinary genius, Roger Bacon, although Aristotle had alluded to it, fifteen centuries earlier, as the true method of studying nature. In the sixteenth century we find Paracelsus and his contemporary, Bernard Palissy, vigorously propagating this experimental doctrine, and advocating practice before theory; but even in the middle of the eighteenth these two things were so distant from each other in men's minds that in the public colleges of Paris there was always a lecturer and a demonstrator. Under Louis XV. the demonstrator of the chemical lectures at the Jardin du Roi was Rouelle, and his demonstrations were often exactly the opposite of the theory just before propounded by the lecturer. This Rouelle was a very original personage. We find in him something of Paracelsus and something of Bernard Palissy. He demonstrated very energetically, was apt sometimes to require the assistance of his nephew-his "eternal nephew," as he called him-who was rarely present when wanted. Under these circumstances Rouelle would go himself from the amphitheatre to the laboratory to fetch what he required, continuing his lesson the whole time, and returning to the lecture-room with the exclamation, "Yes, gentlemen, that is what I had to explain to you!" When begged to recommence he would do so in the kindest manner possible, believing that he had not made himself understood. Rouelle was the professor of Lavoisier. If we follow up, in Dr. Hoefer's work, the history of oxygen gas, we pass certainly through some of the most romantic paths in chemistry. Oxygen was obtained for the first time in a state of purity by Eck de Sulzbach, a wandering alchymist, in 1489, by heating red oxide of mercury. But in those days the means of collecting gases were unknown. The pneumatic trough (an invention usually attributed to Priestley, who merely used mercury for the first time instead of water), by which gases may be collected, was invented and described by the poor Parisian student, Maitrel d'Elément, who published a pamphlet upon it in 1719, after being "snubbed" by the Academy, and dedicated it "to the ladies." These are facts, well established by Dr. Hoefer, with which those who are acquainted with his "History of Chemistry" may be already familiar. The history of oxygen in the hands of Jean Ray, Robert Boyle, John Mayow, Priestley, Schéele, and Lavoisier, and the gradually developed theories of combustion and respiration, form some of the most interesting chapters in this volume. There are also some remarkable paragraphs relating to Lavoisier's unfortunate death upon the scaffold it would appear that several "distinguished savants" of that terrible epoch in French history had it in their power to save the life of this wonderful genius, if they had possessed courage to come forward at the last moment, or had they not been restrained by motives distinct from fear. The biography of Charles William Schéele is sketched * Baron Liebig's admirable study of Lord Bacon as a man of science, published some months ago in Macmillan's Magazine, will tend to modify the general opinion entertained in England of this singular mau's experimental (?) philosophy. NOTICES OF PATENTS. GRANTS OF PROVISIONAL PROTECTION FOR Lane, W.C. manufacture of inflammable gases, and in their applica2719. J. Blaggs, Chancery Lane, "Improvements in the tion to useful purposes."-Petition recorded Oct. 21, 1865. 2768. S. Sequelin, Camden Town, "Improvements in the purification and preparation of animal and vegetable wax, stearine, spermaceti, paraffine, and other solid, waxy, or fatty substances."-October 27, 1865. 2786. H. Larkin, Torriano Cottages, Leighton Road, N.W., "Improvements in lamps for the combustion of magnesium, and in preparing magnesium for burning."— October 28, 1865. ments in the treatment and deodorisation of sewage water." 2808. H. Y. D. Scott, Ealing, Middlesex, "Improve-October 31, 1865. 2810. J. Sellars, Manchester, "Improvements in the manufacture of artificial gum, size, or stiffening matter." Street, Spitalfields, 2818. C. H. Wood, Aldgate, and E. L. Barret, Thrawl "An improved mode of purifying gas."-November 1, 1865. 2825. L. Schad, Warrington, Lancashire, "Improveand printing." ments in the manufacture of colouring matter for dyeing J. Webster, Birmingham, "Improvements in generating and applying certain gases, and in apparatus to be employed therein." November 2, 1865. Street, London, "Improvements in the manufacture of 2835. H. Bessemer, Queen Street Place, New Cannon iron and steel, and in apparatus employed in such manufactures." 2838. J. B. Elkington, Newhall Street, Birmingham, "Improvements in the manufacture of copper from copper ore."-November 3, 1865. 2853. J. Thys, Grove Road, Mile End, "An improved non-conducting composition for preventing the radiation or transmission of heat or cold."-November 4, 1865. 2859. A. Paraff, Manchester, " Improvements in printing and dyeing textile fabrics and yarns."-Nov. 6, 1865. 2867. D. Barker, St. James's Street, Piccadilly, "Improvements in the manufacture of bricks and artificial stone and marble."-November 7, 1865. NOTICES TO PROCEED. 1766. John Dale and R. S. Dale, B.A., Manchester, "Improvements in the production of pigments suitable for printing upon paper and woven fabrics."-Petition recorded July 4, 1865. CORRESPONDENCE. New Iron Ore. To the Editor of the CHEMICAL NEWS. SIR,-Permit me, through your columns, to draw the attention of your readers to what appears to myself and others to be an undescribed ore of iron. It has much of the characteristic appearance of plumbago, and leaves a black greasy stain when rubbed between the fingers. It is comparatively soft, and when scratched with a knife falls off the mass in beautiful shining particles, having a metallic lustre and not unlike powdered mica. This mineral is said to have been obtained in Ireland, near the surface, underlying about fifteen feet of peat. Its analysis gives the following percentage : which, though not new, have probably never before found themselves conjoined. Not satisfied with this little eccentricity, the author proceeds to exercise his metamorphic force upon one of these symbols, since the fe in one line is converted in the next into Fe-a change possibly unimportant in his eyes, but which, in a symbol, a thing demanding the utmost exactness of expression, must lead to the conclusion that two distinct compounds are signified by these differences. It would be well, and, indeed, only becoming, that before Dr. Phipson and others of his stamp appear in print, they should consider whether a few rough and incomplete commercial analyses are worthy the attention of any but those who have a pecuniary interest in the matter, and also whether they are justified in placing the results of their crude experiments and deductions therefrom before the public, especially when conveyed in language so careless, confused, and obscure as that of the paper which has provoked these notes. I am, &c., J. DENHAM SMITH. MISCELLANEOUS. The New Chemical Professorship at Oxford. -Sir Benjamin Brodie, Bart., M.A., has been appointed Waynflete Professor of Chemistry at Oxford. This appointment will render vacant the Aldrichian Professorship of Chemistry, which will not be filled up now. The friends of science at Oxford are still few in number, and even these, we are afraid, do not put out all their strength. From the proceedings of a recent meeting to consider a proposed extension of the University, it would appear that a majority in Convocation are still disposed to regard the University as a manufactory for priests. The Vice-Chancellor, we think it was, said that they did not "want more apothecaries and attornies." Under the former designation we suppose the reverend gentleman would include all those students who would devote themselves more particularly to the natural sciences. But to return: should the Aldrichian Professorship not be filled up, we must again insist that the funds would be best employed in establishing chemical scholarships or fellowships which, like the Radcliffe, should only be held for a limited number of years. ANSWERS TO CORRESPONDENTS. SIR,-In this paper Dr. Phipson tells us that a "deposit" or "lode," he does not say which, of phosphatic material has lately been discovered in Wales, and that to supply the want of an analysis in a memoir by Prof. Voelcker on this subject he gives us several analyses of his own, made for, and published with the permission of, some gentlemen, probably a firm of artificial manure makers, at Wolverhampton, whom, doubtless much to their astonishment, he describes as "eminent agricultural chemists." Having effected this transformation, Dr. Phipson next converts, it is to be presumed by metamorphic action, the "deposit or "lode" into a "rock,' which shortly afterwards becomes a "vein," for he proceeds to further enlighten his reader in this manner, In nature this phosphatic rock forms a wide perpendicular vein between clay-schist and pipe-clay, and in the neighbourhood of a dark bituminous limestone." It is possible to form a guess as to the meaning of this sentence; but if interpreted according to its construction, one stumbles hopelessly. It may be presumed that the learned chemist means that this mineral occurs as a vein lying between beds of schistus and pipe-clay, and that a dark bituminous limestone is to be met with close at hand. He then gives no less than four analyses of this substance, which, considering that they appear in a scientific journal, are striking examples both of confused and of unfinished work. In each of these analyses a very considerable proportion of the constituents, varying from 2 to 14 per cent., remains undetermined, being huddled together under one head, as "carbonate of iron, carbonate of lime, and matters not determined." Again, in the two first analyses, the chemist combines the constituents of the mineral, whilst in the two last he gives these constituents separately, permitting the reader to combine them at his leisure. In no instance does he describe the method pursued in these analyses, so as to render it possible to form a judgment of their probable correctness; and not until the conclusion of his paper does he afford any insight to the reason why he regards the alumina as existing in the form of silicate rather than that of a phosphate of this earth. From such analyses, with from 2 to 14 per cent. of undetermined elements, the author labours to construct chemical formulæ descriptive Bullock and Arthur Vacher; "Cholera Prospects," by Tilbury Fox, of this phosphate, and in so doing has employed symbols All Editorial Communications are to be addressed to the Editor, and Advertisements and Business Communications to the PUBLISHER, at the Office, 1, Wine Office Court, Fleet Street, London, E.C. Private letters for the Editor must be so marked. In publishing letters from our Correspondents we do not thereby adopt the views of the writers. Our intention to give both sides of a question will frequently oblige us to publish opinions with which we do not agree. M. P. S.-See present number. Our reporter mislaid his notes. R. L. S.-We have had no experience in the use of Bunsen's battery Thallium. It has only been done indirectly by the use of soda waste, which contains a considerable proportion of lime. The use of carbonate of lime is patented in England. X., Subscriber.There is no colourless salt of rosaniline that we know of. The colourless base is precipitated from a salt on the addition of an alkali. The best account of aniline, &c., is to be found in Dr. Hofmann's Exhibition Report. A full abstract of the part relating to the dyes will be found in a series of articles in Vol. IX. of the CHEMICAL NEWS. Books Received.-"Fresenius' Quantitative Analysis," edited by J. Analysis of a Fresh-water Fossil (Unio) from the Coal 4. From Chloride of Silver.-This may be at once dissolved in ammonia and treated with the sulphite. The silver will be precipitated quite pure. The method is not applicable to old hyposulphite. In all other cases it is easy to follow, and furnishes chemically pure silver. Every salt of silver dissolved in am. monia and treated with the sulphite is reduced, In liquors heated as directed to 104°, the precipitation is completed in about half an hour; but in the cold, twenty-four hours are required, at the end of which time the precipitation is perfect.-Bulletin Belge de la Photographie. The species in question belongs to the genus Unio; it is probably the Unio Urii, Flem., but the exact determination is of little consequence here. An allied species Researches on the Influence of the Electro-negative has been figured by me in my recent work, "The Utili-Elements on the Spectra of Metals, by M. E. DIACON.* sation of Minute Life," p. 191. It is sufficient to note that all the mollusca of this genus are fresh-water mollusca, and that the deposit in which they are formed is a fresh-water formation. The bivalve in question has given me the following composition: 99'85 It has, therefore, the composition of the South Staffordshire iron ores-i.e., of the spathic iron ores of the coal formations. We could not have greater proof that these vast deposits of iron ore, to which England owes so much of her commercial and industrial prosperity, must be looked upon by the geologist as fresh-water formations. Deposited, doubtless, in the first instance, as drated peroxide of iron, like the bog-ore now forming in the Swedish lakes, which (as I have shown elsewhere) swarms with minute organisms, and afterwards reduced to the state of carbonate of protoxide by the constant presence of organic matter in a state of decomposition. (Continued from page 245.) It was mentioned in the last number that all metals do not lend themselves equaily well for the kind of researches described. Chlorides of metals, for example, which give a spectrum with the chlor-hydrogen blowpipe, give ordinarily very characteristic lines, but these are often very transient, and are wanting in definition. Notwithstanding their transitoriness, however, they may sometimes give useful indications. Certain metals-such as manganese, zinc, cadmium, &c., always give the same spectrum, whatever may be the compound employed. The metals which give the best defined results with the haloids are the alkaline-earthy metals, and bismuth and copper. In the experiments about to be described, a gas blowpipe, the blast for which was supplied by a trompe, was used instead of a Bunsen's jet. The flame obtained by this means is narrower, more equable, better directed, and gives no spectrum in the upper part. It also enables the experimenter to operate at different temhy-peratures by regulating the supply of air. With such an apparatus bromide of barium gives a spectrum which differs from that of the metal, by showing the second and third green lines (the lines are always counted from the red to the violet) with much greater brilliancy; with the chloride the increased brilliancy is observed in the third and fourth lines. With bromide of strontium there is seen beyond the fourth red line, a line which belongs neither to the spectrum of the metal nor to that of the chloride. Recovery of Pure Silver from Photographic Residues, by Dr. VAN MONG KHOVEN. 1. From Old Baths.-First filter then add ammonia until the precipitate first formed is re-dissolved; then add sulphite of ammonia, or pass a current of sulphurous acid gas. Afterwards heat the liquor to about 104° F. for about an hour, when all the silver will be precipitated in a state of absolute purity. This method was first suggested, I believe, by M. Stas. After washing the silver a powder obtained as above may be at once dissolved in nitric acid to form nitrate. 2. From Washings.-The washings may be collected in a barrel in which a sheet of copper is placed. The silver will be precipitated in about twenty-four hours. When the liquor has been often renewed, and a quantity of grey powder of silver has collected, it may be dissolved in nitric acid, and treated with ammonia and sulphite of - ammonia as above. 3. From Paper.-Burn the papers one by one so as to get a white ash. Weigh the ashes and treat them with an equal weight of nitric acid diluted with twice its volume of water. All the silver will be dissolved. Filter, and pour the solution into the barrel containing the sheet of copper. Treat the precipitated silver as before. VOL. XII. No. 313.-DECEMBER 1, 1865. Bromide of calcium shows two new red lines. With bromide of copper a spectrum of great brilliancy is obtained, which differs at once from that of copper and also of the chloride. Iodide of barium gives, at the instant it is introduced into the flames, two green lines; one very brilliant but very transitory, and less refrangible than the first green line of baryta; the other partly coinciding with the second. With the iodides of strontium and calcium the differences are not so remarkable. The spectrum of iodide of copper is very beautiful; it presents parts common to the spectra of the chloride and the bromide, but is distinguished from these by the position of the lines more refrangible than the green. Those lines extend much further towards the violet than is indicated in a plate given by Mitscherlich. The iodide of bismuth gives a spectrum generally bathed in diffused light, except in the violet. It differs less from that of bismuth itself than those of the chloride and bromide, but is distinguished by the beautiful indigo line which terminates it. The spectra of bismuth itself, and those of the chloride and bromide, do not extend so far towards the violet. * Abridged from Annales de Chimie et de Physique, Sept., 1865. The fluoride of barium+ gives a spectrum showing six green lines, nearly equidistant; this appearance is owing to the presence of two new lines more refrangible than those belonging to the metal. These two lines appear alone at the first moment, and their brilliancy may be increased by introducing into the flame below the test specimen an easily decomposable fluoride which gives no spectrum. The fluoride of strontium also shows a new line, welldefined, but not brilliant, and having rather less refrangibility than the yellow sodium line. Fluoride of calcium is characterised particularly by a beautiful green line, almost as brilliant as the green line of calcium; it is situated a little beyond the thallium line. The double orange is the most brilliant presented by the spectrum of this fluoride. The fluoride of bismuth and copper give no spectrum. The attentive study of the light emitted by the bromides, iodides, and fluorides demonstrates, then, that the introduction of those salts into a flame determines the appearance of lines which do not exist either in the spectrum of the metals or in that of the chloride. We must, therefore, conclude that these compounds, like the chloride, have peculiar spectra, the superposition of which on that of the metal gives the appearance observed in each of them. From the foregoing experiments we learn that spectrum observations give us the means of determining not only the metal but the electro-negative element combined with it. Unfortunately, very definite results are only obtained with a few of these compounds. Although the spectra of the chloride and bromide of copper are very much alike, it is easy to distinguish one from the other. The part up to the division 130 of the micrometer is almost identical, because of the superposition of the spectrum of copper, which is unavoidable in an oxidising flame. But the lines between 130 and 150, as well as those seen in the indigo and violet, show differences in the two spectra easily to distinguish without having recourse to measurement. For example, the position of the greenish blue lines is characteristic of the bromide, that of the violet lines for the chloride. When the two salts are placed in the flame simultaneously, the green lines of the bromide predominate at the first instant; the first of the double indigo line of the chloride is visible; the superposition of the more refrangible rays of the two spectra give rise to new appearances. The presence of the iodide of copper produces no change of importance; and thus it is easy to recognise at least a chloride and bromide in a mixture of the three salts. Iodide of bismuth gives the clearest indication of iodine; the spectrum of the salt up to 130 is often illdefined and difficult to distinguish from the same part of the bromide and chloride spectrum; but the beautiful violet band which terminates that of the iodide is a convincing proof of the presence of iodine. Fluoride of calcium must always be used to show the spectrum of fluorine. The green line situated about 121 is very brilliant when a very high temperature is employed, and may be considered characteristic of this metalloid. In conclusion, the author recommends in some cases precipitation with nitrate of silver, but instead of using the silver precipitated in the manner directed by Mitscherlich (p. 243), he treats it with sulphuretted hydro All the haloid salts must not be examined with the same flame. A high temperature is necessary for the fluorides, but a less heat serves better for the bromides, and especially for the iodides, gen, saturates one part of the acid liquor with oxide of copper, and the other with freshly precipitated oxide of bismuth. The liquid or the dry residue of evaporation may be tested directly in the flame, the one for chlorine and bromine, the other for iodine as indicated above. Lastly M. Diacon repeats that the spectra given by Kirchhoff and Bunsen for the alkaline-earthy metals are a mixture of the spectra of the oxide and the chloride, as are also the spectra given by Mitscherlich as those of the chlorides. In the former, he says, the spectrum of the oxide predominates; in the second that of the chlorides. A metal, he states, may give different systems of lines, according to the experimental conditions or the nature of the compound experimented upon, and no absolutely specific character can be attached to the spectra given by Kirchhoff and Bunsen: they can only be considered characteristic of the conditions under which they were observed. The paper of Mr. G. J. Scattergood, read before the American Pharmaceutical Association in 1862, showed that the principle supposed to be veratria was associated with a resin possessing greater effect in reducing the force and frequency of the pulse than the alkaloid itself. Dr. Percy's experiments with a sample of purified commercial veratria demonstrated that principle to possess less sedative action than the resin associated with the veratria of veratrum viride. Mr. Scattergood found the resin precipitated from the tincture of veratrum viride after treatment with ether, to possess sedative action to a remarkable degree. As the subject is open to further investigation, the following notes of an examination of the root may perhaps add something to the sum of our information regarding its active constituents. Profiting by the experience of former investigators, the following process was adopted for procuring the active principle of the plant : A fluid extract was prepared according to the formula adopted in the last edition of the United States Pharmacopoeia-viz., thirty-two troy ounces of the root in powder moistened with twelve fluid ounces of alcohol, was introduced into a percolator, and alcohol gradually poured upon it until a pint of tincture had passed. This was set aside, and the percolation continued until five pints more of tincture were obtained. This was distilled to one pint and mixed with the reserved tincture. To the fluid extract (which was slightly acid to testpaper) sufficient acetic acid was added to give a distinct acid reaction, and the extract poured into one half-gallon of water with constant agitation. The mixture was allowed to stand for twenty-four hours, when the resin was collected on a cloth filter. After distilling the alcohol from the solution, evaporation was continued until it was reduced to one pint; it was then filtered |