Prollius’s Method
The suspected substances are boiled with aqueous alcohol, mixed with tartaric acid, and evaporated at a gentle heat. The remaining aqueous solution is then passed through a moistened filter, ammonia added to the filtrate, and the mixture shaken with chloroform. The chloroform is separated, the last trace of the original solution removed by washing with water, three parts of alcohol added, and the fluid evaporated. If strychnine be present, it will now separate out in crystals. This method is applicable only in presence of a considerable quantity of strychnine, and is less serviceable than the one preceding.