MERCURY 527 membrane. This is followed by diarrhoea with bloody stools and accom- panied by tenesmus. The urine is suppressed or scanty, containing blood and albumin. The pulse becomes quick, small and irregular, and collapse soon supervenes. In some cases spasms, tremors, convulsions and uncon- sciousness are observed before death occurs. Gangrenous colitis 55 may be observed, if the patient has survived six or more days. It should be noted that the symptoms are liable to great variation in different cases although the doses have been the same. Salivation, gingivitis and loosening of the teeth with foetid breath are usually common when mercurial vapours are inhaled. Intravenous injections of novasurol and mersalyl as diuretics are some- times followed by dyspnoea, cyanosis, convulsions and death. They may produce death almost suddenly from anaphylactic shock. j Diagnosis.—This has to be diagnosed from arsenical poisoning. The ' symptoms of mercurial poisoning commence sooner, and the acridity and the constriction of the throat are more marked. The Vomited matters and stools more often contain blood. The irritation of the kidneys is also more pronounced. Fatal Dose.—An intravenous injection of 0.06 gramme of metallic mer- cury as a 40 per cent oil emulsion has proved fatal. On the contrary, recovery has followed 27.2 grammes (2 cc.) of metallic mercury injected intravenously with a view to committing suicide.56 Thirty grains of red oxide of mercury taken with an ounce of acetic acid proved fatal to a girl of 17 years within 30 hours.57 The average fatal dose of mercuric chloride for an adult is three to five grains. Its smallest recorded dose is two grains which killed a child.58 Recovery has resulted after the administration of ninety or one hundred grains, or even much larger doses under" prompt treatment by milk, eggs, and emetics. The average fatal dose of mercuric cyanide is ten to twenty grains. That of mercuric nitrate is one drachm, and of turpeth mineral is forty to sixty grains. Six grains is the smallest quantity of calomel which has caused the death of a boy, aged fourteen years, in three weeks from ulceration and gangrene of the face. Fatal Period.—The usual fatal period is 3 to 5 days, but death may take place much sooner or later than this. Treatment—-If vomiting has not already commenced, give emetics or pass the stomach tube cautiously and wash out the stomach with warm water to which carbonate ofj&agnegium has been, added. Albumen in the form of raw white of egg, or vegetable gluten, mixed with a large quantity of skim milk should then be administered; the albuminate of mercury thus formed, although insoluble in water, is soluble in excess of albumen, and is liable to be digested and absorbed if left in the stomach. It must, therefore, be removed by the administration of emetics or lavage of the stomach. Demul- cent drinks may be ad-ministered to protect the stomach wall. Three to four tablespoonfuls of animal_charcoal suspended in about a pint of water should be administered as soon as possible, as it has the great power of absorbing mercury salts. The addition of about five drachms of magnesium sulphate increases the absorptive power of the charcoal and hastens the removal of the ingested poison.59 The stomach may be washed out with 500 cc. of water containing 30 grammes of sodium thiosulphate. Intravenous injection of sodium thiosul- 55. Berger, Applebaum and Young, Jour. Amer. Med. Assoc,, Feb. 27, 1932, p. 700. 56. Leschke, Clin. Toxic., Eng. Transl. by Stewart and Dorrer, 1934, p. 33. 57. Brit. Med. Jour., Vol. I, 1896, p. 19. 58. Taylor, Prme. and Pract. of Med. Juris., Ed. X, Vol. n, p. 360. 59. Leschke, Clin. Toxic., Eng. Transl. by Stewart and Dorrer, 1934, p. 43.