=Corrosive Sublimate= (perchloride of mercury) is in heavy colourless masses of prismatic crystals, possessing an acrid, metallic taste. It is soluble in sixteen parts of cold and two of boiling water. Soluble in alcohol and ether, the latter also separating it from its solution in water. _Symptoms_ come on rapidly. Acrid, metallic taste, constriction and burning in throat and stomach, nausea, vomiting of stringy mucus tinged with blood, tenesmus, purging. Feeble, quick, and irregular pulse, dysuria with scanty, albuminous or bloody urine or total suppression. Cramp, twitches and convulsions of limbs, occasionally paralysis. In poisoning from the medicinal use of mercury, there may be salivation, a coppery taste in the mouth, peculiar foetor of breath, tenderness and swelling of mouth, inflammation, swelling and ulceration of gums (cancrum oris), a blue line on the gums, and the loosening of teeth. Mercury is less quickly eliminated from the body than arsenic. In chronic cases 'mercurialism,' 'hydrargyrism,' 'ptyalism,' or 'salivation,' including most of the symptoms enumerated above. May get _eczema mercuriale_ and periostitis. Profound anaemia often a prominent symptom; neuritis not uncommon. If fumes of mercury inhaled, mercurial tremors develop. _Post-Mortem Appearances._--Corrosion, softening, and sloughing ulceration of stomach and intestines. The mucous membrane of the oesophagus and stomach is often of a bluish-grey colour. The large intestine and rectum are often ulcerated and gangrenous. Inflamed condition of urinary organs, with contraction of the bladder. _Treatment._--Encourage or produce vomiting. Albumin, as white of egg, gluten, or wheat flour, is the best antidote. Demulcent drinks, milk, and ice. Stomach-tube to be used with care, owing to softened state of gullet and stomach. _Fatal Dose._--Three grains in a child. _Fatal Period._--Half an hour the shortest. _Method of Extraction from the Stomach._--A trial test may be made of the contents of the stomach with copper-foil. If mercury is found, the contents of the stomach may be dialyzed, the resulting clear fluid concentrated and shaken with ether, which has the power of taking corrosive sublimate up, and thus separating it from arsenic and other metallic poisons. The ether allowed to evaporate will leave the corrosive sublimate in white silky-looking prisms. Suppose no mercury is found in the dialyzed fluid, owing to the fact that corrosive sublimate enters into insoluble compounds with albumin, fibrin, mucous membrane, gluten, tannic acid, etc., we must dry the insoluble matter, and heat it with nitro-hydrochloric acid until all organic matter is destroyed and excess of nitric acid expelled. The residue dissolved in water, filtered, and tested with copper-foil, etc. _Tests._--The following table gives the action of corrosive sublimate with reagents: