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sell assayed powder. If the manufacturer or wholesale dealer did it, how would it be done? Often well done, but, perhaps, sometimes badly. And if badly done it would be difficult to detect. It is not difficult to make an assay of powdered or moist Opium in its natural condition, but when skillfully adulterated the assay becomes very much more difficult. The most convenient and most commonly used adulterants of powdered Opium are the different starches and gums, and these very much complicate and delay all the processes of assay. Standardizing Opium at once hands it over into the do. main of adulteration, and it would be very difficult to tell whether any given sample was standardized or simply adulterated, and it would be an excellent defence to set up in a prosecution by Boards of Health that this important article was not adulterated but only standardized. It is true the Pharmacopæia might,-as it should, direct that the diluent used should be a definite inorganic substance which could be readily determined, and which would not interfere with the processes of assay. Still it is a very dangerous step for the Pharmacopeia to take to introduce a practice of dilution and admixture, for it would have all the force of legalized adulteration. In the judgment of this writer those considerations far overbalance the great advantages that would accrue from having a strictly uniform strength for powdered Opium. The accuracy of therapeutic practice is the main argument for such uniformity, and it is a very strong argument. But when it is considered that the dose of an opiate varies so much from idiosyncrasy, and from the varying conditions to which the dose must be adjusted, the argument loses much of its force, especially in view of the probability that an assayed powder would be sufficiently effective in securing practical uniformity. If patients and their conditions in their reactions with Opium were like chemicals in their reactions, then a very definite strength would be necessary. But, unfortunately, this is not the case.

The least objectionable method of having an arbitrary standard would be to place it so high that the ordinary grades of Opium would not reach it. Then the pulping of a portion of the Opium and straining out a proper proportion of the insoluble inert residue would be necessary. The chief objection to this would be the heating necessary to evaporate the solution and washings, as such heating always injures the alkaloid.

A matter of very great importance to the new Pharmacopæia is to get a good process for the assaying of Opium, and it is a prominent part of the objects of this paper to offer one which, with a very

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little practice, will be found moderately accurate, and as simple, convenient and easy as the moderate degree of its accuracy will admit. Many processes of assay have been published, some original, and others made up from the best points of preceding ones, but all have left something still wanting, and the general defect of all has been that they do not get all the morphia which the Opium contains. During many years, the writer has used a modification of the Staples process with general success; but there are many points of uncertainty in the process, and a good deal of skill and experience are necessary to know when its results are trustworthy and when they need repetition; but with due care and repetition the results are moderately and practically trustworthy. Nevertheless, all the published processes have been fairly tried as they were proposed, and none so satisfactory have been found until within the past two years. The process of Mohr, by lime as a solvent and ammonium chloride as a precipitant, when modified by the use of alcohol and ether in the precipitation, is a very good process, but the frothy mixture is uncleanly, and often very difficult to exhaust,--the proportion of ammonium chloride is insufficient, and even when increased is not so good a precipitant as free ammonia, and hence it is probably that. the results are always too low. It has always been suspected, too, though never proven, that the solution of calcium chloride held a larger proportion of the morphia from crystallizing out than in other processes where this salt is not present. Doubtless, in all practicable processes some morphia is held in a condition not to be accounted for, and it is very desirable to reduce this proportion to a minimum. For the purposes of the Pharmacopeia the lime process is objectionable, because it does not so well apply to the liquid preparations as other processes. Some two years or more ago (date lost by not being put upon the translation which the writer had made), Professor F. A. Flückiger, of Strassburg, published a most excellent and elaborate paper on the assaying of Opium, which is the best contribution to the subject made for many years. It is not entirely fair to the author to give a translation of a part of his paper when the whole is so necessary to the subject, especially when the translation, too is of unknown degree of accuracy;* but the paper is a long one, and the writer hopes his friend may excuse him for the mutilation of his valuable work. After stating the difficulties of exhausting the Opium, Prof. F. goes on to say :

* This writer does not rearl German, and when Prof. Flückiger's paper appeared, the writer had it translated by some person now unknown, who proved to be not a good translator, though perhaps not inaccurate.

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It is therefore quite expedient, from our point of view, not to attempt a more or less complete exhaustion of the Opium, nor to have recourse to pressing out, but in accordance with an analytical proceeding used sometimes, to employ only one part of the watery extract for the determination of the amount of morphia. If one shakes the Opium with a suitable amount of water, and gains by filtration, for instance, half of the same, then half of the morphia passed over into: the water must be contained in the filtrate. The objection against this may be obviated when one considers that 60 per cent of the Opium is dissolved. Then one must add to the weight of the filtrate to be drawn off 30 per cent. of the weight of the opium powder operated on, and then it will contain one-half the morphia. To be precise, it would be necessary, in every particular instance, to find out how much the water contained by the opium weighs.

The quantity of opium powder to be taken for quantitative determination is. best limited to 8 grammes. The 8 grammes with 80 grammes of water are put in a closed bottle, and left, with frequent sbaking, during half a day, and are then brought upon a many-folded filter 125 m.m. in diameter Under ordivary circumstances, from 65 to 68 c. c. run through. It appears to be immaterial whether, by employing a water air-pump, a larger quantity be obtained. 48.52 of the ingredients of the Opium are to be considered as dissolved. 42.5 grammes of the filtrate contains the morphia from 4 grammes of the Opium powder. One puts the 42.5 grammes of Opium extract into a small tared fask of about 100 c.c. capacity. Then one weighs into the flask 12 grammes of alcohol of .815 sp. gr., with 10 grammes of ether ; that is, the solution of Opium receives: an addition of one-quarter its volume of alcohol and one-third of ether, and is not clouded. Finally, one adds to the brown mixture 1.5 gramme of ammonia of sp. gr. of .960, over which, after shaking, a colorless stratum of ether is. formed. The ether is indispensable. It keeps the narcotine, which may have passed over with the water, in solution. The chief advantage, however, of the ether is that the morphia crystallizes completely, and in a very pure condition from the solution of diluted alcohol saturated with ether. The flask, well corked, is placed quietly aside; after an hour it sh ws the first traces of crystallization at the surface of contact between the two strata. After standing twelve hours the crystallization will be complete, and will consist of a consid-erable quantity of slightly yellowish or brownish crystals. To make certain, one may allow it to stand twelve hours longer without detriment

Then one folds two filters of 10 c.m. in diameter in the shape of a star, places them together in a capacious funnel, and moistens them with alcohol and ether, which are mixed in the proportions mentioned above. Now you shake the morphia thoroughly with the mother liquor, bring it on the filter, and cover the funnel with a glass cover. After the liquid has passed through, you rinse the flask: little by little with about 10 grammes of alcohol and ether, and finally with as much ether, without paying any attention to the morphia sticking to the glass. You take the filters from the funnel, allow them to dry in the air, and put the crystals of morphia, which are easily detached, back into the tared flask, which is dried at a temperature of 100°, and then weighed. It pow contains all the morphia that was separated in tbe form of a hydrate of the formula C17, H19, NO:+H20, with 5.94 . per cent. of water. The fluid flows rapidly down through the star filter, and the considerable mass of paper and the use of the double filter, and takes up under cautious pressure the remnant of the mother liquor from the crystals. It is, therefore, more advisable not to weigh the filtere.

The filtrate is then mixed with 5 c.c. of ammonia, corked, and observed again a day after, in order to obtain a certainty that no more morpbia crystallizes out. If you allow the mixture to remain standing in an open glass, those above mentioned amorphous flakes will separate.

42.5 grammes of the filtrate treated in the above mentioned manner gave me from 405-433 of morphia. It is a good plan to use the rest of the filtrate as a check assay, or to use 63.75 grammes in place of 42.5 grammes.

At the same time one may render acid a few c.c. of the filtrate with hydrochloric acid, shake them with a double volume of ether, allow tbis to evaporate, and treat the residue with a few grammes of water. Then these will con

tain enough of meconic acid to present, after the addition of iron chloride, the blood-red coloration. This reaction of meconic acid is concealed in the unal. tered Opium extract by the presence of the morphia, and may, therefore, be adduced in this manner as characteristic of the Opium.

The criticisms which this writer diffidently makes upon this excellent process, are as follows:

If the writer's opinion be accepted that an Opium assay which accounts for the morphia contained within 0.25 per cent, is sufficiently accurate for present pharmacopæial purposes, and for all practical purposes, then the exhaustion of all ordinary unadulterated Opiums to a practically useful extent is not difficult. The writer has exhausted two portions of 10 grammes, each of the same rich powdered Opium, by a way to be described—the one was exhausted to 225 cubic centimetres of solution, and the other to 150 cubic centimetres. The solutions yielded, under the same conditions of assay, practically the same amount of morphia. The use of an aliquot part of a given solution to represent an aliquot part of a partially soluble substance, dissolved and suspended in it, was proposed many years ago for Opium and cinchona barks, by P. Carles, probably, and was then tried by the writer without success.

The discarded portion always contained, proportionately, more of the active elements than the portion taken. Nevertheless, when again recommended by an authority so high, who knew what had been done by his predecessors, the subject was well worth re-examination, and it was carefully tried by the writer, critically by the directions given, Opium of known morphia strength being used, check assays being made, and one portion being totally exhausted for another check. The first portion of the solution gave •544 gramme of morphia. The discarded portion gave '595 gramme of morphia, and the two added together did not account for the morphia known to be present in the Opium by about 1 per cent. The total being too low, was, however, shown by a check assay to be due to another cause, namely, the large volume of solution used for precipitation. Prof. Flückiger uses 42.5 grammes of solution, representing 4 grammes of Opium, for precipitation; but if this solution be evaporated on a water bath to about 10 cubic centimetres, and 6 cubic centimetres of alcohol and 12 cubic centimetres of ether be added, considerably more mor. phia will crystallize out with the same quantity of ammonia. The addition of alcohol, before precipitation, is essential and common to many processes. But the addition of ether, which, so far, as the writer knows, is peculiar to Prof. Flückiger, is a very great additional

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advantage to the process; and the proportion of ether recommended can be increased with additional advantage. The watery extract and the alcohol should be shaken together before the ether is added in order that a combination may be made. Then, after the ether is added, the mixture should be again shaken before the ammonia is added. The quantity of ammonia recommended seems excessive, but it is essential to the success of the process, and should even be exceeded a little, especially for Opium rich in morphia. Instead of setting the flask aside to crystallize, it is much better and gives a cleaner morphia to shake the flask vigorously until the crystals separate. With shaking, this always occurs in from 5 to 10 minutes, and if the shaking was continued for half an hour, the crystallization would probably be complete. But this has not yet been proved by check assays. In pouring the mixture onto a filter wetted with a mixture of ether and alcohol, as recommended, the filtration will often go on all right, but occasionally it is very slow and tedious, and the ethereal stratum on the surface will evaporate, precipitating the narcotine, etc., held in solution by it, to a greater or less degree, to be weighed as morphia. Therefore, it seems to be better practice to use a tared filter inside and an untared one outside-to wet these with ether, and then to carefully pour off the ethereal layer first into the filter with as little of the watery portion as practicable, and then to add a second portion of ether to the flask without shaking, and again pour off as much ether as practicable. And then, in order, this time, to get as much off as possible, a little of the dense watery solution may be allowed to pass into the filter with the last of the ether. Then, by covering the funnel and allowing the ether to pass through almost entirely before the watery solution is poured on, almost all the matters dissolved by the ether will be avoided. If the edges and sides of the filter be then washed down by about 5 cubic centimetres of ether before the dark, watery solution with the remainder of the ether is poured on, it will still further secure this result. When the watery solution has about half of it passed through, the flask should be rinsed out with water and the rinsings, with all the crystals, be poured onto the filter. If the shaking has been active while the crystals were forming this will leave the flask nearly clean. Anything in the interior of a flask is very difficult to dry, and from this reason such substances are often weighed when imperfectly dried. But by getting almost all the crystals onto the filter the inside of the flask is comparatively easy to dry, and there is less risk of weighing moist crystals. Then, as

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