SULPHURIC ACID 455 plaster suspended in water, or eggwhite, should be administered without delay, and should be followed by demulcent drinks, such as barley water, linseed tea, etc. Later on Bismuth Subcarbonate in 30 grain doses may be 'given. The use of alkaline carbonates or bicarbonates should be avoided as far as possible, as they evolve carbon dioxide gas, which will increase distress, and may even cause perforation by suddenly distending the stomach. Intense thirst should be relieved by giving pieces of ice to suck, and pain should be relieved by hypodermic injections of morphine. Nutrient enemata should be given to keep up the strength of the patient. Excoria- tions on the surface must be treated as burns. Tracheotomy must be resorted to, if suffocation is threatened from an affection of the larynx. Post-mortem Appearances.—The conditions found after death depend upon the quantity and strength of the acid used, and the time that the patient survives after taking the acid. If death has occurred in a short time there will be signs of corrosion and destruction of the mouth, throat, oesophagus and stomach varying from a few localized patches to extensive destruction. There may be perforation of the stomach with the escape of its contents into the peritoneal cavity, and consequent destruction of the peritoneum and abdominal organs. The tissues beyond the corroded area show the signs of inflammation. If the patient lived for some days, the signs of repair due to separation of the sloughs will Be evident, and the cicatrized tissue will be noticeable, if death did not occur for a very long time. The marks of corrosion may also be noticed on the skin and clothes. Medico-legal Points.—Cases of poisoning by corrosive, mineral acids are rare in India, but are more frequent in Europe. They are rarely used for homicidal purposes though cases are sometimes met with in which cor^sives are thrown on the face out of jealousy or in fits of rage. Accidental cases of swallowing acids in mistake for some harmless medicine do occur especially amongst children. Occasionally a cooly, while carrying a jar conaining some concentrated mineral acid, may accidentally fall down, and break the jar so as to spill the acid which may affect him, as also the passers-by. A few suicidal cases also occur. SULPHURIC ACID (OIL OF VITRIOL), H2SO4 O Properties.—Pure sulphuric acid is a colourless, heavy, oily liquid, which emits no fumes, when exposed to the air. When mixed with water, it evofees much heat, and is reduced in volume: It chars and blackens the skin, cloth and any other organic matter. The portion of the cloth or paper which comes into contact with the acid is destroyed, leaving a reddish-brown stain which is usually moist. Similarly, the stain on wood is damp black owing to its charring effect. x The sulphuric acid of coarinaerce is usually "brown or dark in colour, and often contains impurities, such as lead sulphate, arsenic, nitric acid and tite lower oxides of nitrogen. A stronger form of the acid is known as Iferdr hausen acid which is a brown, oily, fuming liquid and is represented fef tife formula H^O?. It is also called pyrosulphuric acid, and is used in fte manufacture of indigo. Sulphate of indigo is a dark blue liquid, and com- sists of one part of indigo dissolved in nine or ten parts of sulpjferic acli r. / Sulphuric ac|ct apd its preparation, Acidum sulpfcuricttm 5 to 60 minipis); "V^er^ indtided in the British Pharmac been ^tetei *fr^ of aroma$^m> ^M^^^kmn. as "elixir dE vitriol, dose ''