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Academy of Sciences—Notices of Books.
Nov. 24, 1865.
compared his own results with those of Marignac, and treats, in his first section, of the birth of chemistry and expresses a general concurrence with the views of the its gradual development through the periods of Alchymy latter chemist. They agree that hyponiobic, niobous, or and Pneumatic Chemistry to that of Modern Chemistry, dianic acid is only the acid of niobium, corresponding to dating from the epoch of Robert Boyle, where we get the tantalic acid, and concur in thinking that the mineral first glimpses of chemical analysis. Rose experimented with, and prepared the yellow niobic Around the biographical sketches of Boyle, Lavoisier, chloride from, must have contained a considerable quantity Priestley, Schéele, and Davy, in the second division of of tantalum. Marignac regards niobium and tantalum as the work, are grouped those of less famed philosophers, pentatomic metals ; but Blomstrand considers them as a and the discoveries of those facts upon which has been bi- or tetratomic. We shall probably hear a good deal of built the present colossal and useful structure of modern niobium before the question is decided.
chemistry. In spite of the disadvantages to which science M. Cailléletet presented a note “ On the Gases contained has ever been submitted in this country, compared with in Cast Iron and Sleel in a State of Fusion." As the France and Germany, English discoveries hold a very metals run into moulds and solidify, a large quantity of prominent position in Dr. Hoefer's work. Indeed, since gas escapes. The author has succeeded in collecting this ihe appearance of his " Histoire de la Chimie,” in two gas and analysing it. We give the percentage composition vols. (for a new edition of which chemists have long been of the gas from grey cast-iron obtained with coke :- waiting), we may safely state that this is the first time Hydrogen, 33'70; carbonic oxide, 57.90 ; nitrogen, 8:40. the history of chemical research has been touched upon He is in doubt whether the nitrogen really escaped from by a truly impartial and extremely competent judge, and the metal, or whether it was derived from air in his England will, we doubt not, be proud of the work. Schéele apparatus. We may give some account of the apparatus and Davy are, upon the whole, the finest flowers in this used, with cast-iron, at a future time. No apparatus the brilliant chemical bouquet, and the section of the book author could contrive would stand the experiment with devoted to them reads with all the interest of romance. The cast iron, and all he can say of the gas escaping from it is, third, and last, portion is devoted to the future of chemistry, that it contained hydrogen and carbonic oxide, but the which our author, acting up to the poet Longfellow's imperfection of his apparatus always admitted air. principles, goes forth to meet “without fear and with a
M. Gernez sent a paper “ On Supersaturated Solutions." manly heart.' It was a reply to M. Jeannel, who attributes the sudden To assert that the origin of chemistry is lost in the crystallisation of supersaturated solutions to purely physical “nuit des temps” is, according to Dr. Hoefer, a sonorous causes. M. Gernez, our readers know, asserts that the phrase which teaches nothing. We must seek this origin crystallisation is brought about by the contact of a solid | in the workshops of the blacksmith, the enameller, the particle, no matter how minute, of the substance held in colour-maker, and the druggist ; nay, even in the kitchens of solution. In his present paper, M. Gernez says, at some our ancestors long before the word chemistry existed. length, that he has repeated all M. Jeannel's experiments, This word, whose origin and meaning has been cause of and has only arrived at results which confirm his own much discussion, the author shows to date from the fourth views.
or fifth century, and to signify the art of melting or disM. Maumené presented a note “On the Origin of the solving. The birth of the process of distillation is traced Sulphuretled Waters of the Pyrenees." The author believes back to the time of Pliny. Aristotle, who lived three he has discovered a double sulphide of iron and sodium in centuries earlier, knew that liquids were evaporated by the slaty schist through which the water rises at Cauterets; heat, and that their steam condensed again by cold, but and he makes the announcement at this moment in order Pliny gives (in his Nat. Hist., xv. 7) the first vestige of a that all the scientific world may take notice and stand distilling apparatus. He says, " The fire is lit under the aside while he continues the studies necessary to demon. pot which contains the resin ; the vapour rises and constrate that which at present he only believes to be extremely denses on the cloth which is spread over the orifice of probable, viz., the existence of a double sulphide of iron the pot; when the operation is finished the cloth, impregand sodium in all rocks from which sulphuretted waters nated with oil, is squeezed.” issue.
In ancient times the art of manipulating and the art We cannot understand upon what principle the public of thinking-in other terms, the artisan and the philocation of papers in the Comptes-Rendus is regulated. We sopher-were separated by an immense abyss; and before find, for instance, the following :-M. Zaliwski read note arriving at the state of alchemy, the science of chemistry “concerning a law, which, according to him, enables us had to wade through a very curious “sacred" period, to to recognise à priori the solvents of iodine." The note is which Dr. Hoefer has devoted some interesting pages. not published; but whatever it may have been, it could This sacred or divine art was first practised by the Egyptian hardly have been more stupid than some that are published priests. The evaporation of water was observed to leave every week.
a sediment of earthy matter whilst the vapour rose in the
air ; hence it was concluded that water was transformed NOTICES OF BOOKS.
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. Chemistry and its Founders : Ferdinand Hoefer, La Chimie The oxide heated in its turn with grains of wheat repro
enseignée par la Biographie de ses Fondateurs. Paris : duced the lead ; this was the revivification or resurrection Hachette. 1865.
of the metal. " The grains of wheat," says Dr. Hoefer, To instruct, to amuse, and to furnish matter for thought were the symbol of resurrection or of immortality, as
"instruire, plaire, et donner à penser"-has been Vr. appear to attest the little satchels of wheat found with Hoefer's object in writing the charming little volume the Egyptian mummies." The alchemists knew, amongst before us, and among the valuable works of this dis- other things, that copper dissolves in nitric acid, and that tinguished author we have here one which will assuredly when a piece of iron is thrown into the solution the copper take a very high place. Since the appearance of Liebig's is deposited whilst the iron disappears. Let us place our. well-known " Letters on Chemistry and the late Pro- selves in the position of the alchemists in presence of this
essor Johnston's "Chemistry of Common Life" there pseudo-curious fact, should we not have said, as they did, has been no work calculated to inspire so intense a love that the iron was transformed into copper? The famous for chentical research in the student, or to afford so much theory of the transmutation of metals reposed, indeed, upon interest to the professional chemist, as the present volume. well-observed facts, but facts which were erroneously
Starting from the commencement of things, Dr. Hoefer | interpreted. As to the philosopher's stone, we are here
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 space to quote from it. Born on December 19, 1742, at may judge what sort of a life an alchemist led, our author Stralsund, he became assistant to an apothecary at the gives the history of the enthusiastic Denis Zacaire, born age of 14. It was in the midst of the most obscure occuin 1510, who, having inherited a small fortune from his pations that Schéele perfected himself in the study of a parents, was robbed, first by an Arab, then by a Greek, science which owes to him more discoveries than to any next by a French or a German adept, until his little income other man. The history of his career will encourage, for was almost entirely wasted in the vain pursuit. Zecaire years to come, those whose first love for chemical research tells us himself that he did, thank Heaven, finally succeed is attended with more than ordinary difficulties. In 1786 in forming gold; but whilst on his road to some place in he married the widow who had given up to him the little Germany, where he was going to enjoy the fruits of his pharmacy at Kjöping, which yielded him about 600 francs supposed discovery, the poor fellow met with a mournful à year, and died two days after his marriage, at the end-he was assassinated at Cologne by his fellow-traveller. age of not quite 44 years. The King, wishing to recom
After a while what is called the experimental method pense a man whose name was so familiar to him, had his dawned (300 years before the time of Lord Bacon *) with name added to the list of Swedish knights, but his that extraordinary genius, Roger Bacon, although Aristotle minister, little acquainted with the savants of the day," had alluded to it, fifteen centuries earlier, as the true sent the order to the wrong person-some lucky homonyme. method of studying nature. In the sixteenth century we
With this we must take leave, at least for the present, find Paracelsus and his contemporary, Bernard Palissy, of Dr. Hoefer's very interesting and instructive volume. vigorously propagating this experimental doctrine, and
T. L. PHIPSON, Ph.D., F.C.S. 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
NOTICES OF PATENTS. Paris there was always a lecturer and a demonstrator. Under Louis XV. the demonstrator of the chemical GRANTS OF PROVISIONAL PROTECTION FOR lectures at the Jardin du Roi was Rouelle, and his demon
SIX MONTHS. strations were often exactly the opposite of the theory just communicated by Mr. Vaughan, PATENT AGENT, 54. Chancery before propounded by the lecturer.
Lane, W.O. This Rouelle was a very original personage. We find in him something of Paracelsus and something of Bernard manufacture of inflammable gases, and in their applica
2719. J. Blaggs, Chancery Lane, “Improvements in the Palissy. He demonstrated very energetically, was apt tion to useful purposes."- Petition recorded Oct. 21, 1865. sometimes to require the assistance of his nephew-his "eternal nephew,", as he called him--who was rarely the purification and preparation of animal and vegetable
2768. S. Sequelin, Camden Town, “ Improvements in present when wanted. Under these circumstances Rouelle wax, stearine, spermaceti, paraffine, and other solid, waxy, would go himself from the amphitheatre to the laboratory or fatty substances."–October 27, 1865. to fetch what he required, continuing his lesson the whole
2786. H. Larkin, Torriano Cottages, Leighton Road, time, and returning to the lecture-room with the exclama. N.V., “Improvements in lamps for the combustion of tion, “Yes, gentlemen, that is what I had to explain to magnesium, and in preparing magnesium for burning."'you!" When begged to recommence he would do so in October 28, 1865. the kindest manner possible, believing that he had not made himself understood. Rouelle was the professor of ments in the treatment and deodorisation of sewage water."
2808. H. Y. D. Scott, Ealing, Middlesex, “Improve. Lavoisier.
-October 31, 1865. If we follow up, in Dr. Hoefer's work, the history of
2810. J. Sellars, Manchester, “ Improvements in the oxygen gas, we pass certainly through some of the most manufacture of artificial gum, size, or stiffening matter." romantic paths in chemistry. Oxygen was obtained for the first time in a state of purity by Eck de Sulzbach, a Street, Spitalfields, “An improved mode of purifying
2818. C. H. Wood, Aldgate, and E. L. Barret, Thrawl wandering alchymist, in 1489, by heating red oxide of
1, 1865. mercury. But in those days the means of collecting gases were unknown. The pneumatic trough (an invention ments in the manufacture of colouring matter for dyeing
2825. L. Schad, Warrington, Lancashire, " Improveusually attributed to Priestley, who merely used mercury and printing.” for the first time instead of water), by which gases may be
2833. J. Webster, Birmingham, “Improvements in collected, was invented and described by the student, Maitrel d’Elément, who published a pamphlet be employed therein." -November 2, 1865.
generating and applying certain gases, and in apparatus to upon it in 1719, after being." snubbed” by the Academy, and dedicated'it “ to the ladies." These are facts, well Street, London, “Improvements in the manufacture of
2835. H. Bessemer, Queen Street Place, New Cannon established by Dr. Hoefer, with which those who are iron and steel, and in apparatus employed in such manuacquainted with his “ History of Chemistry" may be
factures." already familiar. The history of oxygen in the hands of
2838. J. B. Elkington, Newhall Street, Birmingham, Jean Ray, Robert Boyle, John Mayow, Priestley, Schéele, and Lavoisier, and the gradually developed theories of
Improvements in the manufacture of copper from copper
"-November combustion and respiration, form some of the most interest
3, 1865. ing chapters in this volume. There are also some remark: non-conducting composition for preventing the radiation
2853. J. Thys, Grove Road, Mile End, “An improved able paragraphs relating to Lavoisier's unfortunate death
or transmission of heat or cold.”-November 4, 1865. upon the scaffold : it would appear that several“ distinguished savants" of that terrible epoch in French ing and dyeing textile fabrics and yarns.”—Nov. 6, 1865.
2859. A. Paraff, Manchester, " Improvements in printhistory had it in their power to save the life of this wonderful genius, if they had possessed courage to come
2867. Ď. Barker, St. James's Street, Piccadilly, “Imforward at the last moment, or had they not been restrained provements in the manufacture of bricks and artificial
stone and marble."—November 7, 1865. by motives distinct from fear. The biography of Charles William Schéele is sketched
NOTICES TO PROCEED.
1766. John Dale and R. S. Dale, B.A., Manchester, Baron Liebig's admirable study of Lord Bacon as a man of science, “ Improvements in the production of pigments suitable published some months ago in Macmillan's Magazine, will tend to modify the general opinion entertained in England of this singular for printing upon paper and proven fabrics." --Petition mau's experimental() philosophy.
recorded July 4, 1865.
CHEMICAL NEWS, 254 Miscellaneous-Answers to Correspondents.
Nov. 24, 1865. which, though not new, have probably never before found CORRESPONDENCE.
themselves conjoined. Not satisfied with this little eccen
tricity, the author proceeds to exercise his metamorphic New Iron Ore.
force upon one of these symbols, since the fe in one line is To the Editor of the CHEMICAL News.
converted in the next into Fe-a change possibly unimSIR, Permit me, through your columns, to draw the portant in his eyes, but which, in a symbol, a thing deattention of your readers to what appears to myself and manding the utmost exactness of expression, must lead to others to be an undescribed ore of iron. It has much of the conclusion that two distinct compounds are signified the characteristic appearance of plumbago, and leaves a by these differences. black greasy stain when rubbed between the fingers. It It would be well, and, indeed, only becoming, that is comparatively soft, and when scratched with a knife before Dr. Phipson and others of his stamp appear in falls off the mass in beautiful shining particles, having a print, they should consider whether a few rough and inmetallic lustre and not unlike powdered mica. This complete commercial analyses are worthy the attention of mineral is said to have been obtained in Ireland, near the any but those who have a pecuniary interest in the surface, underlying about fifteen feet of peat. Its analysis matter, and also whether they are justified in placing gives the following percentage :
the results of their crude experiments and deductions Insoluble (in HCl and NO3)
therefrom before the public, especially when conveyed in Ferric oxide
language so careless, confused, and obscure as that of the paper which has provoked these notes.
I am, &c., J. DENHAM SMITH. This mineral is quite unacted upon before the blowpipe, and contains no carbonaceous matter whatever. I enclose
MISCELLANEOUS. a small fragment for your inspection. I am, &c.
JNO. SUTHERLAND. 314, Duke Street, Glasgow, November 21,
The New Chemical Professorship at Oxford.
-Sir Benjamin Brodie, Bart., M.A., has been appointed Notes on the “ Analysis of the Phosphatic Rock recently Waynflete Professor of Chemistry at Oxford. This apDiscovered in Wales, by Dr. T. L. Phipson."
pointment will render vacant the Aldrichian Professorship
of Chemistry, which will not be filled up now. The friends To the Editor of the CHEMICAL News.
of science at Oxford are still few in number, and even SIR,In this paper Dr. Phipson tells us that a " deposit”, these, we are afraid, do not put out all their strength. or " lode,” he does not say which, of phosphatic material From the proceedings of a recent meeting to consider a has lately been discovered in Wales, and that to supply proposed extension of the University, it would appear that the want of an analysis in a memoir by Prof. Voelcker on a majority in Convocation are still disposed to regard the this subject he gives us several analyses of his own, made University as a manufactory for priests. The Vice-Chanfor, and published with the permission of, some gentlemen, cellor, we think it was, said that they did not "want probably a firm of artificial manure makers, at Wolver- more apothecaries and attornies." Under the former hampton, whom, doubtless much to their astonishment, designation we suppose the reverend gentleman would he describes as “eminent agricultural chemists.” Having include all those students who would devote themselves effected this transformation, Dr. Phipson next converts, it more particularly to the natural sciences. But to return: is to be presumed by metamorphic action, the “deposit should the Aldrichian Professorship not be filled up, we or “lode” into a “rock,” which shortly afterwards must again insist that the funds would be best employed becomes a "vein,” for he proceeds to further enlighten in establishing chemicalscholarships or fellowships which, his reader in this manner, " In nature this phosphatic like the Radcliffe, should only be held for a limited number rock forms a wide perpendicular vein between clay-schist of years. 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 accord- ANSWERS TO CORRESPONDENTS. ing 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
All Editorial Communications are to be addressed to the EDITOF,
and Advertisements and Business Communications to the PUBLISHER, at and pipe-clay, and that a dark bituminous limestone is to
the Office, ,!, Wine Office Court, Fleet Street, London, E.C. Piirote be met with close at hand. IIe then gives no less than letters for the Editor must be so marked. 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
In publishing letters from our Correspondents we do not thereby
adopt the views of the writers. Our intention to give both sides of a analyses a very considerable proportion of the constituents, question will frequently oblige us to publish opinions with which we varying from 2 to 145 per cent., remains undetermined, being do not agree. huddled together under one head, as carbonate of iron, carbonate of lime, and matters not determined.” Again, M. P. S.-See present number. Our reporter mislaid his notes. in the two first analyses, the chemist combines the con- Dr. Muspratt. - Declined, with tbanks. stituents of the mineral, whilst in the two last he gives with bichromate of potash and sulphuric acid.
R. L. S.-We have had no experience in the use of Bunsen's battery these constituents separately, permitting the reader to
GeLoro - Next week. combine them at his leisure. In no instance does he Thallium. - It has only been done indirectly by the use of soda describe the method pursued in these analyses, so as to
waste, which contains a considerable proportion of lime. The use of render it possible to form a judgment of their probable
carbonate of lime is patented in England.
X., Subscriber.—There is no colourless salt of rosaniline that we correctness ; and not until the conclusion of his paper know of. The colourless base is precipitated from a salt on the addidoes he afford any insight to the reason why he regards the tion 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 alumina as existing in the form of silicate rather than that
to the dyes will be found in a series of articles in Vol. IX. of the of a phosphate of this earth. From such analyses, with CHEMICAL NEWS. from 2 to 145 per cent. of undetermined elements, the Books Received." Fresenius' Quantitative Analysis," edited by J. author labours to construct chemical formulæ descriptive L. Bullock and Arthur Vacher ; ** Cholera Prospects," by Tilbury Fox, of this phosphate, and in so doing has employed symbols Received. -"Formula."
Dec. 9, 1885. **,} Influence of Electro-negative Elements on the Spectra of Metals.
255 SCIENTIFIC AND ANALYTICAL
4. From Chloride of Silver.-This may be at once
dissolved in ammonia and treated with the sulphite. CHEMISTRY.
The silver will be precipitated quite pure.
The method is not applicable to old hyposulphite. In Analysis of a Fresh-water Fossil (Unio) from the Coal all other cases it is easy to follow, and furnishes chemi
Measures, by Dr. T. L. PHIPSON, F.C.S., fc. cally pure silver. Every salt of silver dissolved in am. The fossil of which I have just made the analysis is monia and treated with the sulphite is reduced. In found near Tipton, South Staffordshire, in some pits liquors, heated as directed to 104°, the precipitation is belonging to one of my friends. I believe it is the first completed in about half an hour ; but in the cold, time that any of these fossils have been submitted to twenty-four hours are required, at the end of which time careful analysis, and the result is rather remarkable.
the precipitation is perfect.--Bulletin Belge de la PhotoThe species in question belongs to the genus Unio ;
graphie. 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
(Continued from page 245.) that all the mollusca of this genus are fresh-water mollusca, and that the deposit in which they are formed is do not lend themselves equaily well for the kind of re
It was mentioned in the last number that all metals a fresh-water formation. The bivalve in question has searches described. Chlorides of metals, for example, given me the following composition :Carbonate of iron
which give a spectrum with the chlor-hydrogen blow
pipe, give ordinarily very characteristic lines, bat these
are often very transient, and are wanting in definition. manganese
Notwithstanding their transitoriness, however, they may Phosphoric acid .
sometimes give useful indications. Certain metals-such Silicate of alumina
as manganese, zinc, cadmium, &c., always give the same Water
spectrum, whatever may be the compound employed.
The metals which give the best defined results with 99-85
the haloids are the alkaline-earthy metals, and bismuth It has, therefore, the composition of the South Staf- and copper. In the experiments about to be described, fordshire iron ores-i. of the spathic iron ores of the a gas blowpipe, the blast for which was supplied by a coal formations. We could not have greater proof that trompe, was used instead of a Bunsen's jet. The fame these vast deposits of iron ore, to which England owes so obtained by this means is narrower, more equable, better much of her commercial and industrial prosperity, must directed, and gives no spectrum in the upper párt. It be looked upon by the geologist as fresh-water forma- also enables the experimenter to operate at different temtions. Deposited, doubtless, in the first instance, as hy- peratures by regulating the supply of air. With such drated peroxide of iron, like the bog-ore now forming an apparatus bromide of barium gives a spectrum which in the Swedish lakes, which (as I have shown else- differs from that of the metal, by showing the second and where) swarms with minute organisms, and afterwards third green lines (the lines are always counted from the reduced to the state of carbonate of protoxide by the red to the violet) with much greater brilliancy; with the constant presence of organic matter in a state of decom- chloride the increased brilliancy is observed in the third position.
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 Recovery of Pure Silver from Photographic Residues, chloride. by Dr. VAN MONG KHOVEN.
Bromide of calcium shows two new red lines. With 1. From old Baths. First filter then add ammonia bromide of copper a spectrum of great brilliancy is obuntil the precipitate first formed is re-dissolved ; then tained, which differs at once from that of copper and also add sulphite of ammonia, or pass a current of sulphurous of the chloride. acid gas. Afterwards heat the liquor to about 104° F.
Iodide of barium gives, at the instant it is introduced for about an hour, when all the silver will be precipitated into the flames, two green lines; one very brilliant but in a state of absolute purity. This method was first sug- very transitory, and less refrangible than the first green gested, I believe, by N. Stas. After washing the silver line of baryta; the other partly coinciding with the a powder obtained as above may be at once dissolved in second. With the iodides of strontium and calcium the nitric acid to form nitrate.
differences are not so remarkable. 2. From Washings. The washings may be collected The spectrum of iodide of copper is very beautiful; it in a barrel in which a sheet of copper is placed. The presents parts common to the spectra of the chloride and silver will be precipitated in about twenty-four hours. the bromide, but is distinguished from these by the posiWhen the liquor has been often renewed, and a quantity tion of the lines more refrangible than the green. Those of grey powder of silver has collected, it may be dissolved lines extend much further towards the violet than is inin nitric acid, and treated with ammonia and sulphite of dicated in a plate given by Mitscherlich. The iodide of - ammonia as above.,
bismuth gives a spectrum generally bathed in diffused 3. From Paper.- Burn the papers one by one so as light, except in the violet. It differs less from that of to get a white ash. Weigh the ashes and treat them bismuth itself than those of the chloride and bromide, with an equal weight of nitric acid diluted with twice but is distinguished by the beautiful indigo line which its volume of water. All the silver will be dissolved. terminates it. The spectra of bismuth itself, and those Filter, and pour the solution into the barrel containing of the chloride and bromide, do not extend so far towards the sheet of copper. Treat the precipitated silver as the violet. before.
* Abridged from Annales de Chimie et de Physique, Sept., 1865. VOL. XII. No. 313. DECEMBER 1, 1865.
CHEMICAL. News, On Veratrum Viride.
Dec. 1, 1865. The fluoride of bariumt gives a spectrum showing six gen, saturates one part of the acid liquor with oxide of green lines, nearly equidistant; this appearance is owing copper, and the other with freshly precipitated oxide of to the presence of two new lines more refrangible than bismuth. The liquid or the dry residue of evaporation those belonging to the metal. These two lines appear may be tested directly in the flame, the one for chlorine alone at the first moment, and their brilliancy may be and bromine, the other for iodine as indicated above. increased by introducing into the flame below the test Lastly M. Diacon repeats that the spectra given by specimen an easily decomposable fuoride which gives no Kirchhoff and Bunsen for the alkaline-earthy metals are spectrum.
a mixture of the spectra of the oxide and the chloride, The fluoride of strontium also shows a new line, well as are also the spectra given by Mitscherlich as those of defined, but not brilliant, and having rather less refrangi- the chlorides. In the former, he says, the spectrum of bility than the yellow sodium line. Fluoride of calcium the oxide predominates; in the second that of the chlois characterised particularly by a beautiful green line, rides. A metal, he states, may, give different systems of almost as brilliant as the green line of calcium; it is lines, according to the experimental conditions or the situated a little beyond the thallium line. The double nature of the compound experimented upon, and no orange is the most brilliant presented by the spectrum absolutely, specific character can be attached to the of this fuoride. The fluoride of bismuth and copper spectra given by Kirchhoff and Bunsen : they can only give no spectrum.
be considered characteristic of the conditions under The attentive study of the light emitted by the which they were observed. 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 PHARMACY, TOXICOLOGY, &c. spectrum of the metals or in that of the chloride. We must, therefore, conclude that these compounds, like the On Veratrum Viride, by CHARLES BULLOCK. chloride, have peculiar spectra, the superposition of which on that of the metal gives the appearance The sedative action of veratrum viride has been so well observed in each of them.
attested by the experience of medical practitioners, that From the foregoing experiments we learn that spec- its therapeutical claims have been acknowledged by trum observations give us the means of determining placing two preparations of the plant in the present not only the metal but the electro-negative element Pharmacopæia of the United States. A number of exacombined with it. Unfortunately, very definite results minations, to determine the chemical constituents of the are only obtained with a few of these compounds. root of veratrum viride, have resulted in the isolation Although the spectra of the chloride and bromide of of an alkaloid which answered in general character to copper are very much alike, it is easy to distinguish one
veratria. from the other. The part up to the division 130 of
The paper of Mr. G. J. Scattergood, read before the the micrometer is almost identical, because of the super- American Pharmaceutical Association in 1862, showed position of the spectrum of copper, which is unavoidable that the principle supposed to be veratria was associin an oxidising fame. But the lines between 130 and ated with a resin possessing greater effect in reducing 150, as well as those seen in the indigo and violet, show the force and frequency of the pulse than the alkaloid differences in the two spectra easily to distinguish with itself. Dr. Percy's experiments with a sample of puriout having recourse to measurement. For example, the fied commercial veratria demonstrated that principle position of the greenish blue lines is characteristic of the to possess less sedative action than the resin associated bromide, that of the violet lines for the chloride. When with the veratria of veratrum viride. Mr. Scatterthe two salts are placed in the flame simultaneously, the good found the resin precipitated from the tincture of green lines of the bromide predominate at the first veratrum viride after treatment with ether, to possess instant; the first of the double indigo line of the sedative action to a remarkable degree.. As the subject chloride is visible; the superposition of the more re- is open to further investigation, the following notes of frangible rays of the two spectra give rise to new appear to the sum of our information regarding its active con
an examination of the root may perhaps add something ances. The presence of the iodide of copper produces no change of importance ; and thus it is easy to recognise
stituents. at least a chloride and bromide in a mixture of the three
Profiting by the experience of former investigators, the salts.
following process was adopted for procuring the active Iodide of bismuth gives the clearest indication of principle of the plant:iodine; the spectrum of the salt up to 130 is often ill- A fluid extract was prepared according to the formula defined and difficult to distinguish from the same part adopted in the last edition of the United States Pharmaof the bromide and chloride spectrum ; but the beautiful copæia-viz., thirty-two troy ounces of the root in powder violet band which terminates that of the iodide is a con- moistened with twelve fluid ounces of alcohol, was introvincing proof of the presence of iodine.
duced into a percolator, and alcohol gradually poured Fluoride of calcium must always be used to show the upon it until a pint of tincture had passed. This was set spectrum of fluorine. The green line situated about 121 aside, and the percolation continued until five pints more is very brilliant when a very high temperature is em- of tincture were obtained. This was distilled to one pint ployed, and may be considered characteristic of this and mixed with the reserved tincture. metalloid.
To the fluid extract (which was slightly acid to testIn conclusion, the author recommends in some cases paper) sufficient acetic acid was added to give a distinct precipitation with nitrate of silver, but instead of using acid reaction, and the extract poured into one half-gallon the silver precipitated in the manner directed by Mits- of water with constant agitation. The mixture was cherlich (p. 243), he treats it with sulphuretted 'hydro- allowed to stand for twenty-four hours, when the resin All the haloid salts must not be examined with the same flame. alcohol from the solution, evaporation was continued
was collected on a cloth filter. After distilling the A high temperature is necessary for the
fluorides, but a less heat until it was reduced to one pint; it was then filtered serves better for the bromides, and especially for the iodides,