Kakodyle, Or Cacodyle (As2c4h12), a coupled compound of arsenic and methyle, expressed by the name arsendimethyle. The substance is a highly poisonous liquid, heavier than water, gives forth vapors of specific gravity 7.1, which have a most disgusting odor, and takes fire spontaneously on exposure to the air. It boils at 338° F., and solidifies in square prisms at 43° F.; it is soluble in alcohol or ether, but scarcely so in water. It unites as a base directly with oxygen, and probably with sulphur and chlorine also; and it furnished the first instance of the isolation of an organic metallic basyle. It is obtained by decomposing its chloride by granulated zinc, or its sul-phuret by means of mercury. The preparation of the compounds of kakodyle is difficult and dangerous. The oxide obtained by distilling equal parts of dried acetate of potash and arsenious acid is an impure quality of the fetid liquid formerly known as Cadet's fuming liquor, or alkarsine, which inflames spontaneously on exposure to the air.