For the separation of an alkaloid, the following is the process of Stas-Otto. This process is based upon the principle that the salts of the alkaloids are _soluble in alcohol and water_, and _insoluble in ether_. The pure alkaloids, with the exception of morphine in its crystalline form, are _soluble_ in ether. Make a solution of the contents of the stomach or solid organs minced very fine by digesting them with acidulated alcohol or water and filtering. The filtrate is shaken with ether to remove fat, etc., the ether separated, the watery solution neutralized with soda, and then shaken with ether, which removes the alkaloid in a more or less impure condition. The knowledge of these facts will help to explain the following details, which may be modified to suit individual cases: (1) Treat the organic matter, after distillation for the volatile substances just mentioned, with twice its weight of absolute alcohol, free from fusel oil, to which from 10 to 30 grains of tartaric or oxalic acid have been added, and subject to a gentle heat. (2) Cool the mixture and filter; wash the residue with strong alcohol, and mix the filtrates. _The residue may be set aside for the detection of the metallic poisons, if suspected._ Expel the alcohol by careful evaporation. On the evaporation of the alcohol the resinous and fatty matters separate. Filter through a filter moistened with water. Evaporate the filtrate to a syrup, and extract with successive portions of absolute alcohol. Filter through a filter moistened with alcohol. Evaporate filtrate to dryness, and dissolve residue in water, the solution being made distinctly acid. Now shake watery solution with ether. (3) Ether from the acid solution dissolves out _colchicin_, _digitalin_, _cantharidin_, and _picrotoxin_, and traces of _veratrine_ and _atropine_. Separate the ethereal solution and evaporate. Hot water will now dissolve out _picrotoxin_, _colchicin_, and _digitalin_, but not cantharidin. (4) The remaining acid watery liquid, holding the other alkaloids in solution or suspension, is made strongly alkaline with soda, mixed with four or five times its bulk of ether, chloroform, or benzole, briskly shaken, and left to rest. The ether floats on the surface, holding the alkaloids, except morphine, in solution. (5) A part of this ethereal solution is poured into a watch-glass and allowed to evaporate. If the alkaloid is volatile, oily streaks appear on the glass; if not volatile, crystalline traces will be visible. If a volatile alkaloid, add a few pieces of calcium chloride to ethereal solution to absorb the water; draw off the ethereal solution with a pipette, allow it to evaporate, and test the residue for the alkaloids, conine and nicotine.