excess of saturated solution of potassium iodide to 100 c.c., and then seeing that the iodine set free exactly requires 100 c.c. of "hypo." for complete decolorization, starch paste being added as an indicator towards the end of the process.

As the first step in the experiment, the specific gravity of the sample is taken at 60° F. 10 c.c. are digested with sufficient potassium hydrate in a small strong glass flask, closed by a cork, through which passes a bent delivery tube, dipping under a column of mercury in a test tube, of such a height as will enable the operator to heat gently on a water-bath under pressure without bursting the flask. This point is ascertained by a blank experiment, during which the flask is wrapped in a cover to prevent accident; and once arrived at, the same flask and mercury column are always employed. After digestion under pressure with frequent agitation for some time (an hour being usually ample), water is added, and the contents of the flask evaporated in a basin until no smell of spirit is perceptible. The residual liquid having been rendered just neutral with sulphuric acid, is filtered into a flask containing 75 c.c. of permanganate solution, previously diluted to 200 c.c. with water, and acidulated with 20 c.c. diluted sulphuric acid (1 in 3), and the flask having been corked is left for half an hour. At the end of that time excess of saturated solution of potassium iodide is added (which should produce a clear deep orange solution), and the whole brought under a burette containing the hyposulphite solution, and titrated. The number of c.c. of "hypo." used is deducted from the number of c.c. of permanganate put in, and the difference multiplied by 00375 gives the amount of ethyl nitrite in the 10 c.c. taken for analysis; and if this be multiplied by 100 and divided by 10 times the specific gravity of the original spirit, the answer will be the percentage of ethyl nitrite by weight. In working with spirits of unknown strength, it is advisable to put only 20 c.c. of the permanganate into the flask at first, diluted and acidulated as directed, and then if all the colour disappears under five minutes, to add 5 c.c. more at a time, until a permanent colour is obtained lasting five minutes, when the addition of another 5 c.c. will suffice before setting aside for the half hour. In a good spirit it is sufficient to take 5 c.c. for analysis, and to use 35 to 38 c.c. permanganate.

Analyses of six authentic samples, all of which were prepared in strict accordance with the Pharmacopoeia directions, showed but a slight variation in the proportion of ethyl nitrite present, the lowest percentage being 2:85, and the highest 3:05.

T

It is advisable to perform a blank experiment, using 20 c.c. of rectified spirit, and the same weight of potassium hydrate, in the same manner as the ether, and to check it side by side with a sample experiment.

The Valuation of Tincture of Opium. Prof. A. B. Prescott. (From the Proceedings of the American Pharmaceutical Association.) The author examined twelve samples of tincture obtained from different sources, employing both Hager's and Staples' processes for the estimation of morphine in opium.

Hager's process, modified for the tincture and in other details, was conducted as follows:-The specific gravity of the tincture was taken, and a weighed quantity (from 25 to 30 grams) evaporated nearly to dryness on a water-bath; 1 gram of freshly slaked lime was added, with trituration, then 24 c.c. of distilled water added, and the mixture heated on a water-bath for one hour. The whole was then transferred to a small filter previously wetted, and the residue of the filtration washed with warm water until the filtrate dropped nearly colourless, and the filtrate evaporated on a waterbath to about 25 grams. The liquid was transferred, with rinsings, to a small wide-mouthed bottle, and while it was still warm 1 c.c. of ether and 3 drops of benzole were added with shaking, then 1·1 gram of ammonium chloride added and dissolved, and the mixture set aside for twenty-four hours. The liquid was then agitated, the crystals detached from the interior of the bottle, the whole brought upon a small filter, previously dried and weighed, the crystalline residue washed with about 8 c.c. of distilled water, dried at about 50° C. (122° F.), and weighed. Hager directed to leave the mixture three hours for separation of morphine. He has also advised to deduct one-tenth for impurities in the crude morphine of the process (the crystals not being washed with ether or chloroform). But the filtrate, about 25 grams, if holding only one-thousandth of its weight of morphine in solution, would carry about 0.025 of the alkaloid, fully as much as the one-tenth for foreign substances weighed with the morphine. Now when twenty-four hours are given for crystallization of morphine, there can scarcely be less than one part of morphine in 1000 parts of the filtrate. It is not likely, however, that one-tenth the weight of the crystals (not etherwashed) is as much as the impurities. It will be seen from the results given with Staples' process that the ether-washing alone removes a variable quantity, averaging not far from one-tenth the weight of the crystals, and ether-washing certainly does not leave absolute morphine. The author advises ether-washing of the crude

morphine in Hager's process for the tincture, and then leaving remaining impurities to balance the morphine remaining in the filtrate.

Staples' process was employed in the following manner :-The specific gravity of the tincture having been ascertained in the first place, 25 grams were evaporated to one-half their bulk on the water-bath, then set aside twenty-four hours for the tarry matters (soluble in alcohol but not in water) to subside, and decanted upon a filter, the filtrate being received in a small wide-mouthed bottle. The tarry residue was washed with 4 c.c. (about 1 fluid drachm) of water, and the washings filtered into the previously obtained filtrate. To the clear liquid in the bottle was added an equal bulk of alcohol of specific gravity 0-835, and then a mixture of 13 c.c. (20 minims) of solution of ammonia (sp. gr. 0.96), with 17 c.c. (25 minims) of alcohol. After agitation, the bottle was closed with a stopper and set aside for four days. The liquid was then agitated, the crystals detached from the side of the bottle, and the whole filtered upon a small filter previously dried and weighed. The last portion of crystals was rinsed from the bottle upon the filter with a little of the filtrate. The crystals were then washed with 4 c.c. (1 fluid drachm) of diluted alcohol, then with the same measure of distilled water, then dried at about 50° C. (120° F.), and weighed. The dried crystals were then washed with 8 c.c. (2 fluid drachms) of washed ether, dried at 50° C., and again weighed.

The directions in Staples' process are to leave twenty-four hours for crystallization of the morphine, and to add the ammonia in two. portions, in both which particulars the process was departed from.

The process of Hager, it will be seen, takes less time than that of Staples; but the time depends greatly on the period given for formation of morphine crystals. By long standing a slightly

greater yield is obtained.

The author concludes that Staples' process yields the best crystals of morphine, but considers that in other respects it is little if at all preferable to Hager's method.

Taraxacum. Dr. C. Symes. (From a paper read before the Pharmaceutical Society, and printed in the Pharm. Journ., 3rd series, x., 361.) Referring to the well-known differences of opinion as to the best time of the year for collecting dandelion root, the author states that his own experience points to November as the month in which these roots should be gathered for medicinal use, the period being extended to the beginning of December if the winter has not commenced early; or in other words, the later they are gathered, so

long as they have not been subjected to the influence of frost, the better they will be. At this period, it is true, they contain a large quantity of inulin, but the active principle, or taraxacin, is more fully developed (if bitterness is any criterion) than at any other season, and the inulin can be separated from the expressed juice far more readily than the saccharine matter which abounds in the spring. He has examined samples of the fresh juice late in the autumn which had comparatively little action on Fehling's solution, whilst at other seasons it is very marked and energetic. No sooner does the frosty weather set in than the roots become sweet, the starchy matter becoming converted into saccharine; a necessary condition of things before it can serve the useful purpose in the economy of the plant for which it appears designed, viz., for the nourishment of the root during the cold weather. This is probably brought about under the influence of a ferment which operates specially at low temperature; but that starch, even in the absence of a ferment, and in the cold, may be gradually converted into dextrine, has recently been shown by Ribau (Bull. Soc. Chim., xxxi., 10), and as regards the change in dandelion roots, no one who will take the trouble to examine them before and after a few sharp frosts will have the least doubt as to the increased sweetness. The author's first impression was that the bitter principle remained intact, and was merely masked by the presence of the saccharine matter, but experiment led him to the conclusion that it became more or less altered in character, and that its destruction went on pari passu with that of the inulin.

As to the preparations of taraxacum, the solid extract is not regarded by medical men as an agent of much activity, except in large doses; the succus, on the other hand, is much prescribed, not unfrequently in too small doses, but when well prepared and moderately fresh is a good representative of the medicinal properties of the drug. When, however, it is kept for any length of time, and more especially in warm weather, it often becomes turbid, deposits, and sometimes ferments, losing most of its bitterness, and this will, as a matter of course, occur much more readily in the presence of a large quantity of saccharine matter than in its comparative absence. Reasons which it will be unnecessary to detail render it undesirable to increase the quantity of alcohol in any medicinal preparation of the kind, beyond the amount necessary for its complete and perfect preservation, but especially in that under consideration, where the quantity administered is or should be comparatively large. But in the formula given a minimum of spirit is used at a

risk of the stability of the preparation, and the author, therefore, suggests an increase of about 5 per cent. of spirit. The dose as regards bulk might be diminished by concentrating the filtered juice as soon as possible after expression from the roots.

In conclusion, the author bears testimony to the value of the fluid extract of taraxacum officinal in the United States Pharmacopoeia, which he regards as a strong, efficient, elegant, and stable preparation.

Experiments on Taraxacum Root. J. B. Barnes. (From a paper read before the Pharmaceutical Society, April 21st, 1880, aud printed in the Pharm. Journ., 3rd series, x., 849.)

Experiment No. 1.-In order to exclude inulin (which in the autumn is so very abundant and necessary to the development of the plant, gives considerable trouble, and causes much waste in preparing the succus, and is not completely separated from the extract), clean, fresh taraxacum root in thin slices, with the milky juice exuding, was covered with rectified spirit for two hours, strained and washed with more spirit, and the clear liquor evaporated over a water-bath to dryness, the result being a bright canarycoloured hygroscopic powder, possessing an intensely bitter taste and perfectly soluble in water.

Experiment No. 2.—The above preliminary operation being wasteful of spirit, one pound of clean, fresh, thinly-sliced root was macerated with an equal weight of spirits of wine for two days, the liquid poured off, the marc pressed and the product filtered, the spirit recovered by distillation, and the solution evaporated over a water-bath to the consistence of an extract, which is bitter and of a light brown colour. The quantity obtained was one ounce and a half.

Experiment No. 3.-The above operations were repeated, three pounds of another sample of fresh root being now employed; but the evaporation was continued to dryness and the product powdered, the result being a yellowish hygroscopic powder. It possesses a bitter taste, but not so intense as that obtained in Experiment No. 1, the pressure having extracted something, probably sugar and other matters, in addition. A small quantity of inulin was pressed out, which, however, was readily separated by filtration. The quantity of dry extract obtained was three ounces and a quarter.

Experiment No. 5.-Half a pound of dried taraxacum root, reduced to powder, was macerated for twelve hours in half a pound. of rectified spirit, and percolated with a further portion of spirit.