[139] Pharm. Journ., Feb. 12, 1875; also for other cases see Brit. Med. Journ., Nov. 4, 1876; and Köhler’s Physiol. Therap., p. 437.
§ 145. In order to separate petroleum from any liquid, the substances under examination must be carefully distilled in the manner recommended under “[Ether].” The lighter petroleums will distil by the aid of a water-bath; but the heavier require a stronger heat; redistillation of the distillate may be necessary. The odour of the liquid, its inflammable character, and its other properties, will be sufficient for identification.
2. COAL-TAR-NAPHTHA—BENZENE.
§ 146. Coal-tar-naphtha in its crude state, is an extremely complex liquid, of a most disagreeable smell. Much benzene (C6H6) is present with higher homologues of the benzene series. Toluene (C7H8), naphthalene (C10H8), hydrocarbons of the paraffin series, especially hexane (C6H14), and hydrocarbons of the olefin series, especially pentylene, hexylene, and heptylene (C5H10, C6H12 and C7H14). Besides these, there are nitrogenised bases, such as aniline, picoline, and pyridine; phenols, especially carbolic acid; ammonia, ammonium sulphide, carbon disulphide, and probably other sulphur compounds; acetylene and aceto-nitrile. By distillation and fractional distillation are produced what are technically known “once run” naphtha, 90 per cent. benzol, 50 and 90 per cent. benzol,[140] 30 per cent. benzol, solvent naphtha, and residue known as “last runnings.”
[140] Or 50⁄90 benzol, this indicates that 50 per cent. distils over below 100°; and 40, making in all 90, below 120°.
§ 147. Taylor[141] records a case in which a boy, aged 12, swallowed about 3 ozs. of naphtha, the kind usually sold for burning in lamps, and died with symptoms of narcotic poisoning. The child, after taking it, ran about in wild delirium, he then sank into a state of collapse, breathing stertorously, and the skin became cold and clammy. On vomiting being excited, he rejected about two tablespoonfuls of the naphtha, and recovered somewhat, but again fell into collapse with great muscular relaxation. The breathing was difficult; there were no convulsions; the eyes were fixed and glassy, the pupils contracted; there was frothing at the mouth. In spite of every effort to save him, he died in less than three hours after taking the poison. The body, examined three days after death, smelt strongly of naphtha, but the post-mortem appearances were in no way peculiar, save that the stomach contained a pint of semi-fluid matter, from which a fluid, having the characteristics of impure benzene, was separated.