On poisons in relation to medical jurisprudence and medicine . tion (Fig. 19) may appear not inan annular form, but in detached nucleated particles of a somewhatglobular shape. These are of an iron-gray color, quite unlike sublimedmercury, and when examined by the microscope, it may be seen thatthey consist of crystalline masses, and that they are angular, and not strictly spherical. This sublimate is some-times produced in the last stage when theresidue in the tube is strongly heated, andthe air is exhausted. The process of reduction with the corrobo-rative results above mentioned, is, whenth
On poisons in relation to medical jurisprudence and medicine . tion (Fig. 19) may appear not inan annular form, but in detached nucleated particles of a somewhatglobular shape. These are of an iron-gray color, quite unlike sublimedmercury, and when examined by the microscope, it may be seen thatthey consist of crystalline masses, and that they are angular, and not strictly spherical. This sublimate is some-times produced in the last stage when theresidue in the tube is strongly heated, andthe air is exhausted. The process of reduction with the corrobo-rative results above mentioned, is, whenthus applied, conclusive of the arsenicalnature of the substance under , selenium, and mercury producesublimates, but these do not possess theappearance or properties of an arsenicalsublimate. Arsenic in Solution in Water—LiquidTests.—A solution of arsenious acid is clear,colorless, possesses scarcely any perceptibletaste, and has but a feebly acid, this state, we should first evaporate slowly a few drops on a glass- Fig. Crystals of arsenious acid from asolution in water, magnified 124diameters. ARSENIC — COPPER TEST. 309 slide, when a crystalline residue will be obtained. On examining thiswith a microscope, it will be found to consist of numerous minute octa-hedral crystals, presenting triangular surfaces by reflected light. (Seeillustration, Fig. 20.) 1. Silver Test.—On adding to the solution ammonio-nitrate of silver,a pale yellow precipitate of arsenite of silver falls down; changing,under exposure to daylight, to a greenish-brown color. The test ismade by adding to a strong solution of nitrate of silver, a weak solu-tion of ammonia, and continuing to add the latter, until the brownoxide of silver, at first thrown down, is almost redissolved. The yel-low precipitate is soluble in nitric, tartaric, citric, and acetic acids, aswell as in ammonia. 2. Copper Test.—On adding to a solution of arsenic ammonio-sul-phate of copper, a ligh
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectpoisons, bookyear1875
