On the detection of strychnia as a poison : and the influence of morphia in disguising the usual colour-test / by John J. Reese.

  • John J. Reese
Date:
1861
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Licence: Public Domain Mark

Credit: On the detection of strychnia as a poison : and the influence of morphia in disguising the usual colour-test / by John J. Reese. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    stances has the effect of disguising, and entirely neutralizing the usual colour-test used for detecting strychnia; so that, although the latter might be undoubtedly present, yet, if morphia were also present at the same time, the strychnia could not be discovered. It will be readily admitted that this is a point of the extremest importance to be settled by the chemist, in medico-legal researches. It is one to which no very especial attention has hitherto been given. It is merely mentioned as a casual fact in the various works on toxicology, but the only actual experiments recorded, to my knowledge, are those published by Dr. T. G. Wormley, in the Ohio Med. and Surg. Journal, for September, 1859, in which it is stated that, when the morphia exceeds the strychnia in quantity, the possibility of discovering the latter by the colour-test diminishes. The author himself lays no par- ticular stress upon the fact. I accordingly undertook a series of experi- ments for the purpose of more accurately determining, if possible, this very important subject, and with the following results :— Experiment 1. One-tenth of a grain of pure strychnia was added to about twelve ounces of water, into which were put several ounces of fresh beef, finely cut up, together with some starch, a little common salt, and a few drops of acetic acid; (the object being to represent, as closely as possible, the contents of a human stomach after a meal.) The whole was digested on a sand-bath for 12 hours at a moderate heat. It was then strained, pressed and filtered; and after- wards evaporated down to a very small bulk. It was next divided into two separate portions, each of which, of course, would contain the ^th of a grain of strychnia. One of these portions was treated after the process known as Graham and Hoffman's (the alkaloid being removed by animal charcoal, and finally ex- tracted by ether). Here, a drop or two of the ethereal solution, representing about the l-40,000th to the l-50,000th of a grain, gave distinct evidence of strych- nia by the usual colour-test. The second portion of the evaporated solution was divided into two parts, each of which would of course contain the ^th of a grain of the alkaloid. The first of these was treated according to the process of M. Sta'as, in which ether is used as the ultimate solvent: and the second part after the process of Mr. Prollius, in which the ultimate solvent was chlo- roform. In both instances I obtained the most satisfactory proofs of the pre- sence of strychnia; operating upon a single drop of the fluids—which would represent, certainly, not over the l-100.000th of a grain of strychnia. Expt. 2. This was a repetition of the former experiment, except that the quantity of strychnia used was much smaller—only the , ^th of a grain. After treatment by Sta'as' process, and on concentrating the ultimate ethereal solution, the presence of strychnia was manifested both by the colour-test, and by the bitter taste of the extract. Here, the quantity of the poison operated upon was less than the l-100,000th of a grain. Expt. 3. This was an exact repetition of Expt. 2, except that to the TJBth of a grain of strychnia, three times that quantity of morphia (^sd of a grain) was added. On treating this by Sta'as' process, as in the preceding cases, I could not discover the slightest trace of either strychnia or morphia, even after the ultimate ethereal solution was concentrated to a very small bulk by evaporation. Now, from the first two experiments just mentioned, in which the pro- cesses used were the precise counterparts of those employed in the analysis of the stomach, I think I am justified in concluding that these processes were extremely delicate and reliable : and that if the poison had been pre- sent, even in so minute a quantity as the T<j,jth °f a grain, it ought to have