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ducts has the constitution of the anhydride of barbaloin, that is to say, is formed by the abstraction of one molecule of water from two molecules of aloin. Dr. Tilden appears to regard barbaloin as having the constitution of a complex phenol ; a view to which several facts give probability.
Dr. Squibb has pointed out that for many years the American market has been supplied with the stem of the Pareira brava in place of the root. So completely has this been the case, that upon meeting with samples of the root, he pronounced them to be fraudulent substitutes for the true drug.
Samples of the oil of peppermint, adulterated with alcohol and castor oil, have been met with in America; a fraud which is very easy of detection. Two tests have been suggested for the recognition of spirit in this oil: one (Puscher's) is to add a few crystals of fuchsin, which, if spirit is present, dissolves, imparting its brilliant colour to the liquid; the other (Hager's) is to introduce a little tannin, which remains unaffected by the pure oil.
The corollas of a scrophulariaceous plant have been met with in American commerce by Mr. J. M. Maisch, under the name of African saffron. Mr. J. R. Jackson suggests that they most probably belong to the Lyperia crocea, a plant of South Africa, the flowers of which closely resemble saffron in smell and taste, and have been used as a yellow dye.
Beeswax is a body well known to be subject to considerable adulteration, and Mr. H. Pocklington has therefore done good service by showing that its purity can be readily determined by microscopi. cal examination. Melted on a glass slide, allowed to cool slowly, and then examined by a 4-inch objective with polarised light, the distinctive crystals of pure wax can be readily distinguished from those of its adulterants. M. Hardy has also published some experiments on this subject. He directs attention to the difference in the specific gravity of wax and suet, and enumerates the densities and mixtures of spirit and water, in which alloys of wax and suet in different proportions will remain suspended.
J. M. Remington has been engaged in examining the quality of commercial glycerin. He decribes the best means of determining its purity, and directs attention to the rise of temperature which occurs when concentrated glycerin is mixed with water. This circumstance he thinks may account for the irritating effects which sometimes result when glycerin is applied undiluted to the skin.
E. A. Letts, by the action of sodium amalgam, or sodium alcohol, on glycerine, has succeeded in obtaining the mono-sodium glycerin, C, H, Na 03, and also the alcoholate of this body. This is decomposed by water into sodium hydrate and glycerin.
The right employment of glycerin in pharmacy is a subject deserving considerable attention. There can be no doubt that it is a most valuable agent for pharmaceutical purposes, and in America it is used in a large number of preparations, perhaps somewhat indiscriminately, while in this country its employment is as yet somewhat limited, and its merits are perhaps not sufficiently recognised. Its functions appear to be twofold: in the first place it is an admirable and special solvent for a number of substances, and in the second place it seems to exercise antiseptic or preservative properties, which are especially useful when the presence of alcohol is not desirable. A valuable application of it has been made by Mr. J. N. Wood, who has shown that when present in tincture of kino in the proportion of about twenty-five per cent., it entirely prevents the gelatinisation which is otherwise so apt to occur. It is also suggested as a useful adjunct in tincture of catechu, and we pointed out last year that it is likely to prove useful in the liquid preparations of cinchona bark, on account of its power to hold cinchonic red in permanent solution.
The extensive use of “elixirs " seems to have become a distinguishing feature of American pharmacy. These preparations, which are as yet but little used in this country, generally consist of one or more active medicinal agents in the form of a dilute syrup or liqueur, associated with various flavouring substances, intended to disguise the taste of the medicines, and render it as palatable as possible.
It is obvious that an almost unlimited scope for variety is thus introduced, and hence these preparations have so rapidly increased and multiplied, that it has become almost impossible for the dispenser to keep them all in stock. The absence of any recognised formulæ for their preparation renders necessary the use of the elixirs issued by various private firms, and thereby adds to the difficulty. An attempt has consequently been made by the Pharmaceutical Associations in America to establish formulæ for these preparations which shall be generally recognised and followed by prescribers and dispensers.
Considerable scope should certainly be given to the ingenuity of individual pharmaceutists for the introduction of new and suitable combinations; but it is to the general interest of the dispenser as well as the patient, that the prescriber should employ, as far as possible, only recognised published formulæ in his prescriptions.
A new and elegant excipient for making a number of substances
into pills has been introduced by Mr. J. B. Barnes. It is the borotartrate of potash, or soluble cream of tartar, the solution of which can readily be obtained of the consistence of mucilage, and in that state is admirably adapted for making such things as sulphur, salammoniac, chloral, or chlorate of potash into pills. Being itself quite colourless, the pills have a very elegant appearance, and can be made hard without impairing their subsequent solution in the stomach.
The success which has attended the introduction of the mustard leaves of M. Rigollot, has induced M. Gurnet to cover in a similar way sheets of paper with linseed. For this purpose the crushed linseed is deprived of its hard skins, and all the oil is removed by means of sulphide of carbon. The mucilaginous portion alone is used therefore. Full details of the method of manufacture are given in our abstraet.
In our text books on chemistry, tannin is generally represented as belonging to the glucosides, a class of bodies which, by the assimilation of water, are capable of splitting up into glucose and some other substance, which in the present case is gallic acid. Glucose, in fact, is regarded as a polyatomic alcohol, of which tannin is the gallic ether. On this view its constitution resembles that of the ordinary oils and fats which are the oleic, stearic, or palmitic ethers of a triatomic alcohol-glycerin. It is well known, indeed, that tannin, prepared in the ordinary manner, is capable, under the influence of hydrating agents, of yielding both gallic acid and glucose. According to the formula assigned to tannin by Strecker, this change can be easily accounted for. Several circumstances, however, have tended to throw some doubt upon the soundness of this view. The proportion of glucose obtainable has been found to vary considerably. Long ago Stenhouse succeeded in obtaining from pure tannin its own weight of gallic acid. Quite recently M. Sacc has published some experiments which entirely confirm the results of Stenhouse. These facts lead to the conclusion that pure tannin is simply the anhydride of gallic acid, and that, as ordinarily prepared, it is accompanied by a variable proportion of a glucoside.
Hugo Schiff has furnished very strong proof of the latter view by effecting the transformation of gallic acid into tannin. By the action of oxychloride of phosphorus or of arsenic acid, gallic acid yields a body identical in all respects with tannin, and capable of reconversion into gallic acid, by the simple fixation of water.
Last year Mr. D. Howard described an alkaloid, possessing special characteristics, met with occasionally in cinchona bark. This alkaloid he has now identified with quinicine, a base obtained by Pasteur from quinine and quinidine by the action of heat. It is interesting to find that a substance which can be artificially derived from these alkaloids should also exist ready formed in the bark. 0. Hesse has also given a preliminary description of a new alkaloid which he has obtained from the Cinchona succirubra bark grown in India. This body he names quinamine. It is crystallisable, and forms a well defined sulphate, but the results of analysis are not yet published. The success which has attended the administration of morphia by subcutaneous injection has led to several suggestions for the hypodermic use of quinine, but the difficulty of preparing a sufficiently concentrated and neutral solution for the purpose has, to some extent, stood in the way. Mr. C. Rice prepares for this purpose an ethereal solution of hydrated quina, of such a strength that five minims contain one grain of the pure alkaloid. M. Schlagdenhauffen states that the neutral sulphovinate of quinine is the most soluble salt of this alkaloid, and may be held in solution by less than its own weight of water.
Although several methods have from time to time been devised for determining the percentage of morphia in opium, a thoroughly good process for this purpose still remains a desideratum. W. Stein, on the Continent, and Mr. J. F. Miller, in this country, have recently published methods for opium assay, which are very similar in principle. They are both based on the power which morphia possesses of reducing iodic acid and liberating the iodine. The quantity of morphia is proportionate to the amount of iodine set free, which is judged of by the colour of its solution in chloroform or sulphide of carbon.
M. J. Lefort has made some important experiments on the distribution of atropia in the leaves and roots of the belladonna plant, from which it appears that although the root is sometimes richer in alkaloid than the leaves, the proportion is more variable. On this account, therefore, he considers that the leaves should be preferred for medicinal use. He shows that the young roots are much richer in active principle than the old roots, and that there is no appreciable difference between the wild and cultivated plants.
The active principle of aconite has formed the subject of numerous researches by different chemists since the discovery of aconitia by Geiger in 1833. An important memoir on this subject has been recently published by M. Duquesnel, in which he describes a simple process by which the alkaloid can be obtained in a pure and crystalline condition. The root of Aconitum napellus is exhausted with strong alcohol acidified with tartaric acid, and the tincture evaporated at a very gentle heat (not exceeding 60. C.). The residue is taken up with water, agitated with ether (to remove colouring matter), then saturated with an alkaline bicarbonate, and again saturated with ether.
Aconitia crystallises from the ethereal solution in colourless rhombic tables. The alkaloid appears to be very prone to change under the influence of heat; a temperature of 100° C. is sufficient for its decomposition. The author appears to consider that aconitia has the constitution of a glucoside, although no very decisive experiments on the point are as yet published. He has studied the salts of the alkaloid, and has obtained the sulphate, muriate, sulpho-cyanide, aconitate, and the nitrate. The latter salt crystallises with great facility in fine rhombs and short prisms, a fact previously pointed out by Mr. Groves in an important paper read before the Conference meeting in 1866. The salt is perfectly neutral, well suited for hypodermic injection, and the best adapted for general medicinal use.
G. H. Weidel has extracted a new base, to which he gives the name of carnine, from extract of meat. It is present to the extent of about one per cent. in Liebig's extract. It crystallises in small irregular crystals, having the composition C, H, N, O, only differing from theobromine therefore by one atom of oxygen.
The author's efforts to transform it into theobromine were unsuccessful, but by the action of bromine water it yields sarcine, C, H, N, O.
A knowledge of the ultimate structure of drugs, as revealed by the microscope, is of growing importance to the pharmaceutist. It not only constitutes the only means of recognising the quality of many articles of the materia medica, but it also often affords the best clue to the means of obtaining the most efficient preparations. We therefore direct attention to the series of papers on this subject, published during the past year by Mr. Pocklington, and noticed in the following pages.