and the same external characteristics; so that he concludes that it is almost certain that they must have resulted from the same process-from the same operation of fire. Every mineralogist knows that certain specific minerals have peculiarities according to the locality, and these must depend upon certain conditions attending their formation. Now, as these crystals of zircon possess such an assemblage of characteristics, I think we may reasonably admit that Deville's conclusion has something like a good foundation to rest upon. Then he further remarks, it may be demonstrated that the small quantities of fluor existing in the metamorphic rocks, or rather beds of this kind, have sufficed to form indefinite quantities of zircon. We shall, by-and-by, direct attention to the subject of fluor, which may have played a very important part in the economy of nature, a much more important part than many persons are yet disposed to admit. It is, as we shall see, a very widely-diffused element, though occurring only in small quantity. When the same experiment, to which I alluded, was made entirely with zirconia, instead of alumina, the whole contents of the tube were completely transformed into zircon. Zircon occurs in rocks which, there is reason to believe, have been exposed to a tolerably high temperature. It occurs in the syenite of Norway, for example, replacing felspar; so that the rock consists only of hornblende, zircon, and a small quantity of quartz; hence the rock is designated" zircon-syenite." The next mineral which it may be interesting to examine is the mineral termed "cryolite," which, in fact, forms a geological bed. It is an exceedingly remarkable mineral. I presented to you a specimen of it at the last lecture, as being a source of aluminium,-a large white lump, fusible at a comparatively low temperature. It is, as I then told you, a compound of fluoride of sodium and fluoride of aluminium. Its formula is 3NaFl+ Al,Fl. It is an anhydrous mineral-that is, free from water. It contains about 13 per cent. of aluminium. It is found in Greenland in a layer in gneiss, and in the vicinity of mica. According to Bischoff, there is a quantity of mica about it which he supposes has played a very important part. The bed of cryolite is eighteen feet thick. Cryolite is associated with various minerals which undoubtedly are of aqueous origin. For example, iron pyrites,-though certainly not prepared at a high temperature-copper pyrites, galena, and sparry iron ore, which certainly never could have occurred at a high temperature, these are the associates of cryolite, and they tell us the story of its formation. It is clearly produced by the agency of water as a solvent. It may be produced by melting together directly fluoride of aluminium and fluoride of sodium. It may also be formed in the wet way by digesting fluoride of sodium with excess of hydrochloric acid and common gelatinous alumina. Bischoff supposes mica to have played a very important part as a source of fluorine,-indeed, as a source of fluorine in common fluor spar which we meet with in so many localities. The next subject for our consideration is one of considerable importance-of the highest importance, I may say. It is that of calcium and lime. All lime, like alumina, contains a metallic base. Calcium, the base of lime, is exceedingly light, has a yellowish colour, is readily fusible, and exceedingly oxidisable, so that it is impossible to expose it to the air without its undergoing oxidation-contrary to what we have seen is the case with aluminium. I understand that recently some important experiments have been made by Wöhler on the subject. He has discovered certain combinations of carbon and calcium, equivalent to those known in ironin the form of pig iron. It is with lime especially, and its compounds, that we have to do. Lime is composed of one equivalent of calcium and one of oxygen. You are all familiar with the properties of lime-an amorphous body, white, or more or less coloured with impurity, and which, on the application of water, slacks; that is, it absorbs water, the water enters into combination with it, and becomes solid, and on its passing from the liquid to the solid state, a large amount of heat is evolved. The lime falls to pieces, having become hydrated, or, in common language, slacked. It is slightly soluble in water, as every one knows, producing the well-known liquid called lime-water. When combined with water-for it must be hydrated-it unites readily with carbonic acid, forming carbonate of lime. Carbonate of lime is a mineral which occurs very extensively in nature, forming beds of chalk, limestone, and two very important minerals, namely, calcite and arragonite. Carbonate of lime is a compound of one equivalent of carbonic acid and one of lime. It is known in three distinct states. There is, first, the amorphous or chalklike state. We will call it chalk. It is perfectly noncrystalline, or amorphous. There is, then, the form of arragonite which occurs in prismatic crystals, and belongs to the prismatic system. The third form of carbonate of lime is that of calcite or calcspar, which is rhombohedral, crystallising in the beautiful rhombohedral crystals with which every mineralogist is familiar. Arragonite varies in specific gravity from 2.93 to 3:01. This is a point to note. The calcite has a lower specific gravity, ranging from 2.69 to 2.75, so that not only in their crystalline system, but also in specific gravity, are these two minerals distinguished clearly from each other. The next point on which I shall speak is the solubility of carbonate of lime. In treating this subject of chemical geology, I am selecting all those points which I conceive have a direct geological bearing; and it is requisite to pay rather close attention, which, perhaps, may be considered tedious, to this part of our subject. One part of carbonate of lime dissolves in 110,000 parts of pure water, in round numbers. It is 110,132 parts really. This carbonate of lime dissolves to a much greater extent when carbonic acid is passed through the water, and it then forms what is termed bicarbonate of lime. One part of carbonate of lime dissolves in 998 parts of water containing carbonic acid, according to Bischoff, the carbonic acid being passed through the water for an hour. He has made several experiments upon this subject, which are remarkable. He finds that the solubility varies to a great extent with the nature of the carbonate of lime operated upon. Thus, 1115 parts of chalk were dissolved in 10,000 parts of water by passing carbonic acid through for an hour. He performed this experiment three times, and each time he obtained pretty nearly the same result; but, when he tried the experiment with carbonate of lime precipitated from a salt of lime, passing the carbonic acid through for about the same time as he did in the experiments with the chalk, he found that 28 parts dissolved in 10,000 parts of water. There is another very striking statement, but which, I think, will require further corroboration. It is, that burnt muschelkalk dissolved to the extent of 135'3 parts in 10,000 parts of water, by passing carbonic acid through the water for an hour and a-half. In passing, I will just mention the fact, that when arragonite is exposed to a red heat, it falls to powder; and it was supposed for a long time that this powder consisted of minute rhombs of calcite. This, however, I find denied by Gustave Rose, who contends that the powder is strictly amorphous. Let us now consider the mode of formation of arragonite, or the conditions under which it may be produced; and, when we understand these conditions, I think we shall find that the information afforded will tend to elucidate the formation of certain geological phenomena, especially with reference to temperature. It will indicate to us the temperature and other conditions under which rocks containing arragonite may have been formed. CHEMICAL NEWB, Jan. 23, 1864. The Weights and Measures of the British Pharmacopeia. 39 Additions and New Names. Tinct. sabinæ. Liq. soda chlorinatæ. Mistura acacia. Myristica oleum. Pil. galbani co. Pil. ferri co. Pil. saponis co. Potassæ bitart. Pulv. cretæ co. iodii. Liquor arsenicalis. terebinthinæ. veratriæ. zinci oxidi. Vin. antimoniale. Zinci valerianas. Some of these changes of name will seem to our readers altogether uncalled for. Why, for example, should Pil. galbani co. for the future be called Pil. assafœtidæ co.? Great confusion also will arise from having an Ext. coloc. co. as well as Pil. coloc. co., inasmuch as prescribers have scarcely got into the habit of prescribing Other the pill when they meant the old extract. changes are open to graver objections; but these we shall leave until we have the entire work before us. colocynth et hyoscyam. As was long ago announced, the Medical Council have aromat. c. opio. ipecac. c. opio. Spirit. cajeputi. chloroformi. ether nitrosi. juniperi. Succus conii. scopariæ. Suppositor. acidi tannici. morphiæ. Syrup. hemidesmi. rosæ gallicæ. Tinct. bucco. 99 camphoræ c. opio. chirettæ. colchici semin. sesquichlor. " ferri perchlor. iodinii co. adopted the avoirdupois pound and ounce in the new Pharmacopoeia. The reasons for it are given in the following extract from the preface to the work. It will be seen that the fluid measure remains the same: 66 Under any circumstances it would have been necessary on this occasion to revise the pharmaceutic weights and measures of the kingdom. But change became imperative for one division or another of the country, as the Dublin College of Physicians, in their last Pharmacopœia, had led the way by adopting for the first time in pharmacy the imperial weights for the ounce and higher denominations; a departure from long established usage which appeared to the Council judicious and worthy of imitation. "The three Colleges had long agreed in adopting the imperial measures for every denomination above the fluid ounce. For the latter denomination a convenient subdivision had been also based on the old pharmaceutic principle, that each fluid ounce should consist of eight parts, called fluid drachms, and each of these of sixty parts, called minims. It was impossible to improve that now familiar division. "The Council, in resolving to adopt for pharmacy the imperial ounce and pound, could not assimilate the subdivision of the ounce to that of the fluid ounce, without substituting a new medical grain for the troy grain, hitherto the medical as well as the standard grain of the kingdom. This alteration they did not consider advisable; it has, therefore, appeared to them a necessary consequence, that the drachm and the scruple, the old denominations of weight between the ounce and grain of pharmacy, must be 1 fluid ounce fl. oz. 1 fluid drachm fl. drm. I minim min. "WEIGHTS. 16 ounces = "MEASURES. = 8 pints 7000 grains. 1 grian. O. viij. 20 fluid ounces fl. oz. xx. 60 minims I minim ... min. lx. min. j." These changes in the weights need not occasion dispensers much trouble. Doubtless, cases will often happen in which it may be open to question whether the troy or avoirdupois ounce is meant; but it can rarely happen that the substitution of either for the other will be of material consequence. Although the drachm and scruple are here omitted from the table, there is no doubt that these weights will be continually used, and it is only necessary to remember that they retain their value in grains, but are no longer aliquot parts of the ounce. PHYSICAL SCIENCE. The Ultra-violet Rays of the Solar Spectrum, by M. MASCART. THE method of obtaining these rays is precisely that used for observing the luminous spectrum. I used a goniometer, with collimator and two lenses of quartz cut perpendicularly to the optical axis, so that the rays traverse them in directions very little inclined on this axis. The refracting prism is also of quartz, cut parallel with the axis, and I generally observed the principal spectrum, which is the most deviating. A system of lenses like this is entirely deprived of achromatism, but this effect does not prevent the production of a pure spectrum, and has no other effect than to cause a considerable change of position when passing from the less refrangible to the more refrangible rays. The mounting of the eye-piece is furnished with a net-work of cross threads, and the eye-piece itself, at its interior extremity, has a photographic plate, with its sensitive face exactly behind the net-work, so as to take the impress of the phenomenon produced on its plane. very small surface always possess sufficiently energetic action, however small the chink may be. I used collodion sensitive enough to give an ordinary photograph in five or six seconds, and the time of exposure in my experiments has never exceeded a minute and a-half. The proofs obtained may be put into a solar microscope, and enlarged positives taken, but the results are mediocre; it is better to examine them by the microscope, to measure the distances of the rays with a micrometric screw mounted on the object-glass, and to draw them very carefully. I obtained my chart in this way; the distances are not exactly proportioned to the deviations, on account of the small variations in thickness. I have more especially endeavoured to reproduce the general aspect, the form of each group, with the relative intensities of the rays. and Esselbach, are already occupied with this question, Some physicists, notably MM. Ed. Becquerel, Stokes, and have indicated by letters the principal groups of rays. Their denominations do not always accord; the charts are sometimes so imperfect as to make it difficult to recognise them, and, besides, names have been given both to the dark and to the brilliant places. I have taken as a guide the plate published by M. Müller in his "Traité de Physique," applying each letter to the most remarkable dark ray in the group it served to indicate. To give an idea of the precision attainable, it will suffice to remark that the luminous spectrum drawn by Fraunhofer comprehends 320 rays, from A to H, and that in an angular space about equal to that from H to S, I found more than 280: the results are then comparable to those obtained with the sun. The dispersion may be increased by multiplying the refracting prisms, as M. Kirchoff has done, for observing in the and comparing [them with the obscure rays of the solar same way the brilliant chemical rays of coloured flames, spectrum. When circumstances allow me I propose to return to this subject. To conclude, the measure of the differences in the length of the wave may be made with adequate exactThe net-work which is before the sensitive plate ness. the ray corresponding to the deviation observed. By is projected and engraven on the proofs; we thus identify arranging a great many similar measurements along the whole length of the chemical spectrum, we may easily, by the help of a chart, fix the deviation of a ray, situated between two positions of the net-work. The lengths of the wave are measured with the same facility. I have obtained very satisfactory results with a net graduated to 440 c. of a millimetre; but I dare not now venture to publish the numbers, as in measuring the lengths of the luminous rays I have arrived at results differing too much from those of Fraunhofer to be accepted without numerous verifications.-Comptes-Rendus, lvii., 789, 63. By this means the chemical region to be explored can, even though invisible, be rapidly brought to view. It is only necessary to produce on the plane of the net-work a defined image of the extreme limit of the luminous spectrum, of the ray H, for instance; the eye-piece is then pushed in a little further to bring the point towards the more refrangible parts, and an experiment is made Soap for Very Dirty Skins.-Under this title by substituting for the eye-piece of the lenses the photo-E. Janota gives the following receipt :-Two pounds of graphic eye-piece. Examination of the result indicates finely rubbed carbonate of magnesia are to be mixed in a in what direction the net-work requires to be displaced. porcelain dish with eight pounds of water-glass and eight The want of achromatism of the lenses admits of clear pounds of rain water. To these four pounds of oleic acid are added, and the whole is gently warmed and stirred as results only within confined limits, and, as the energy long as carbonic acid is evolved. Lastly, a pound of of the action is very unequal in different parts, the time crystallised carbonate of soda dissolved in some warm of exposure ought also to vary; it is then necessary to water is added, and the mass is dried and made into multiply the experiments, and no less than eight trials shapes. The water-glass need not be diluted, as, on mixing it are required to produce the entire chemical spectrum. with carbonate of magnesia, carbonate of potash is formed, which perfectly saturates the oleic acid.-Chemisches Centralblatt, No. 54, 1863. It is obvious that a high degree of perfection of detail may be attained, as the rays concentrated on a NEWS THE BRITISH PHARMACOPOEIA. THE Pharmacopoeia is now completed and printed, and the issue is only delayed until enough copies have been bound to supply at once the immediate demand. We have for some weeks been in possession of the principal novelties in the work, but have refrained from printing them until the work was really published. But as parts have now found their way into the professional prints, and as we are told that at some establishments the new preparations are all made, and bottles labelled ready to place on the shelves the moment it is telegraphed that the Pharmacopoeia is out, we need no longer observe any delicacy. The great delay in the publication of the work is ascribed in the Preface to the following causes : "Numerous researches in chemistry, pharmacy, and natural history, and into the value of old and new remedies, carried on with the complex machinery of a Committee in each of the three divisions of the kingdom, necessarily occupied much time. To these, the principal causes of delay, were added difficulties arising from the present state of the law of copyright, which obliged the Council to apply to the Legislature for an Act of Parliament to enable them to give authority to the British Pharmacopoeia, and to secure a title in the copyright. Further delay was subsequently occasioned by the necessity of altering, in deference to the general wish of the medical profession, the pharmaceutic weights which the Committee had previously adopted in the composition of the work." This statement, while fully accounting for the delay, hardly explains the cost of the book, which is set down by a contemporary at 6000l., but which, we are informed, will more probably amount to 8000l. That matter, however, only concerns the profession whose money the Council spends. The book will be issued in two forms-one at 10s. 6d., the other at 6s. At present, we see no other edition announced, but, no doubt, several will be published, with useful annotations, within a short time of the first issue. The Medical Council, as we have seen, succeeded in obtaining an Act of Parliament to secure them a copyright in the bare work; but there will, of course, be no difficulty in constructing a book to which that Act cannot possibly apply. There are, indeed, grave doubts whether such a thing as a copyright can exist in any work, such as a pharmacopoeia or an Act of Parliament, which is binding on any section of the community. There is no necessity, however, for any enterprising author to try the question. Notes and omissions make an entirely new book. While at this point, we may as well explain the plan we intend to follow in the remarks we shall proceed to make on the work. In the present number we have given a list of most of the new preparations, and of the alterations of names from the last London Pharmacopoeia. In our next notices we shall give a detailed account of the novelties introduced. We shall then proceed to notice the new methods and processes which have been given for preparations under the old names, and also the differences of strength which have been made in some preparations. The following extract from the Preface to the Pharmacopoeia, will show that some of these are important: their Committee from carrying out this principle systematically, because uniformity of medicinal strength in preparations of similar form would be a great safeguard against dangerous mistakes, as well as a great facility alike to the prescriber and dispenser. Nevertheless, the contemplated improvement has been effected extensively, especially in the preparations where it was most required. Thus, among the tinctures, those made with dangerous ingredients are, with few exceptions, brought to one standard of strength, so that an ordinary dose is from fifteen to twenty-five minims; while all tinctures made with substances of no great activity are left, as formerly, uniform in strength, so that an ordinary dose is from one to two fluid drachms." Uniformity of dose will undoubtedly be a safeguard for prescribers with short memories, but we do not see how it will facilitate dispensing. Nevertheless, we regard the change as a decided improvement. From what we have said above, it will be seen that our notices will contain an epitome of all that is new in the book; and, considering the importance of the matter to a large section of our readers, we shall proceed with these notices as early as possible. Researches on Quinoline, by M. HUGO SCHIFF. QUINOLINE combines with metallic salts, and furnishes compounds similar to anilometallic combinations, "H, in quinoline H,N, the general formula of If we admit the presence of a triatomic radical monometallo-quinic compounds will be N X = €,H,N,MX, "Thirdly, an attempt has been made to assimilate the strength of preparations of the same pharmaceutic form, in order that they may be prescribed in similar doses. The Council regret that difficulties of detail have hindered in which X represents an acid radical. For the most VOL. IX. No. 216.-JANUARY 23, 1864. M little soluble in pure water, but much more so in boiling water, with a little nitric acid. This solution deposits the crystalline salt without decomposing it. Prolonged boiling transforms the salt into polymercuro-quinolic compounds. Potash colours it yellow; and it becomes brown when heated. The salt is transformed into a viscous mass, while part of the quinoline volatilises with the aqueous vapour. The nitrate of mercuro-quinoline assists in the double decomposition with the alkaline salts; but the reaction is more precise if the acetate is used. A solution of acetate, heated with the alkaline salts, gives, on cooling, the crystalline salts of different acids. By this method I have obtained hydro-chlorate, -bromate, and -iodate, sulphate, and chromate of mercuroquinoline. All these salts are easily decomposed by raising the temperature. The yellow chromate is transformed at 100° into a viscous mass. Hydrocyanate of mercuro-quinoline, N{H} Cy = €,H,N,CHgN, obtained by direct addition, crystallises, from its aqueous solution, in long brilliant prisms. This compound is attended by none of the phenomena of dissociation belonging to hydrocyanate of mercuraniline. Bichloride of tin, as also the trichlorides of bismuth, antimony, and arsenic, combine directly with quinoline; but these combinations do not possess the remarkable stability of corresponding combinations of aniline. Towards acids, metallo quinolic compounds behave like metallanilides. With the exception of mercuroquinoline, the salts furnish, by decomposition, double compounds, well crystallised and soluble, without decomposition, in acidulated water. The composition of these double salts is not analogous to that of double salts of aniline. While the latter always contain a number of equivalents of aniline equal to the atomicity of the metal, the number of equivalents of the base in double salts of quinoline is often less than that of the atomicity of the metal. We will quote only the following formulas of double chlorides: Zinco-quinolic chloride ZnCl,,H,NCI. SbCl,,,HNCI. SnCl2,H,NCI. Bismo-quinolic chloride . . BiCl 3,H.NCI. Quinoline becomes red when combined with cyanogen. We reserve for some future occasion the results of our researches on other quinolic combinations, and on the decomposition of metallo-quinolic compounds.-ComptesRendus, lvii., 837, 63. The above are the mean results of five experiments at cach different temperature. TECHNICAL CHEMISTRY. The Absorbent Power of Starch for the Coal-Tar By adding wheaten starch to a dilute, cold, aqueous solution of mauve, magenta, azuline, &c., the colouringmatter is absorbed, and the supernatent liquor rendered nearly colourless, when left in contact for a few hours, with occasional agitation to ensure an equal absorption of the colouring-matter by the starch. In the case of azuline, a moderately-strong solution was prepared, and treated with starch as above; every trace of blue was absorbed, and the supernatent liquor had a reddish tinge, due to the red colouring-matter which generally accompanies solutions of azuline. When a more dilute solution of azuline was used, every trace of colour was absorbed, and the liquor on filtration was clear and perfectly colourless. The most of the colouring matter may be removed from the starch again by solution in alcohol. By this process almost every variety of colour may be procured-yellow, pink, various shades of red, blue, mauve, &c. |