6. It has been suggested that the arsenical compound in the soil may be rendered soluble by the ammonia formed during putrefaction.
This last suggestion is negatived by the following facts:
1. The production of ammonia ceases before the body arrives at that stage of decomposition when it is at all likely to be exposed to the action of the soil of the cemetery.
2. The production of hydrosulphuret of ammonia during decomposition would tend to the production of sulphuret of arsenic forming yellow patches in the substance of the organs, thus rather fixing the arsenic on particular parts than allowing it to percolate through the tissues of the body from external application.
Analysis of the Suspected Earth.—About two pounds of the earth should be boiled for some time in water; supernatant liquid should then be poured off from the insoluble residue, and filtered. The filtered liquid, after concentration, may then be examined by the tests about to be described. If no arsenic be found, the earth may now be boiled with dilute hydrochloric acid, filtered, concentrated, and then tested as before. The first process shows that no compound of arsenic soluble in water is present; the second shows that the arsenic is in a state of combination, and therefore not likely to impregnate the body.
The Detection of Arsenic
General Directions.—In cases of suspected poisoning by arsenic or antimony, the contents of the stomach should be mixed with distilled water acidulated with hydrochloric acid and filtered, and the filtrate placed in a stoppered bottle lettered or numbered “A” or “1.” The liver should be cut into pieces, some of which should be bruised in a mortar with distilled water acidulated as above mentioned, pressed and filtered, and the filtrate placed in a bottle marked “B” or “2.”
The kidneys and portions of the other solid organs may also be treated as above. Each solution so obtained may be then tested by the processes about to be described. By these means the amount of poison in each organ may be estimated.
Before subjecting the organic mixture to Marsh‘s or Reinsch‘s processes, Brande and Taylor strongly recommend a modified course of procedure.
The contents of the stomach, vomited matters, &c., and the solid organs, finely divided, must each be separated and thoroughly dried in a water bath, then mixed with an excess of strong hydrochloric acid in a flask, and slowly distilled by means of a sand bath, the distillate carried into a receiver containing a little pure distilled water, and the process continued nearly to dryness.