IRON 555 lips, inside of the cheeks, gums, nostrils, eyelids and lastly the chin. It also affects the viscera, chiefly along the walls of the smaller blood vessels. Albuminuria and paralysis of the extensor muscles common in lead poisoning are also met with. Smith records the case of a patient who took silver nitrate in J— grain doses three times daily for three months for nasal catarrh, when the skin of the face and hands— the exposed surfaces—assumed a darker colour.43 Olson44 cites a case of argyria following the local use of argyrol. A woman sus- tained a fracture of the nose, the laceration of the soft parts extending to the right lower eyelid. In addition to other measures argyrol was dropped into her right eye. The argyrol made its way to the lacerated tissue of the right lower eyelid, nose and cheek, and caused bluish-green and slate-grey pigmentation. Goldstein45 reports a case in which the face, lips and hands became of a peculiar slate-blue colour from the local application of argyrol to the throat twice daily for a year. Treatment.—No treatment of any kind is available for the removal of argyria, although the intradermal injection of equal parts of 12 per cent sodium thiosulphate solution and 2 per cent potassium ferricyanide solution has been recommended,46 but Dr. Acharya, late Professor of Ophthalmology, did not find this method successful in the King George's Hospital, Lucknow. In the case cited by Olson five grains of hexamethylamine were given three tunes a day when argyria improved to some extent. The dose was then increased to ten grains, when after six weeks the signs of irritation in the stomach and kidneys were evident. Post-mortem Appearances.—Pigmentation in the corium, liver and kidneys. Dark colouration of serious and mucous membranes. Chemical Tests.—1. Hydrochloric acid gives a white, curdy precipitate of silver chloride, insoluble in nitric acid, but readily soluble in ammonium hydrate or sodium thiosulphate solution and also on boiling with concentrated sulphuric acid. 2. Potassium chromate gives a red precipitate of silver chromate, soluble in mineral acids, but insoluble in cold acetic acid. 3. Ammonium hydrate added slowly drop by drop to neutral silver solution gives a greyish precipitate of silver oxide, soluble in excess of ammonium hydrate. 4. If a little solid hexamethylene tetramine (hexamine) be added to a drop of neutral silver solution taken on a glass slide, monoclinic plates or needles are visible under the microscope. Medico-Legal Points.—Cases of acute poisoning may occur from the accidental slip- ping of a stick of silver nitrate which is being used to cauterize the throat. A few suicidal cases have occurred after swallowing a stick of silver nitrate. A case47 is recorded where an insane person, aged 31 years, died on the fourth day after swallow- ing a stick of silver nitrate with suicidal intent. A case is also recorded in which a soldier applied lunar caustic to his cornea to evade military duty.48 Silver is partly eliminated in the urine and faeces, but a great deal is retained in the system, and deposited in the tissues. IRON (LOHA) The pharmacopoeia! preparations of iron salts, which are largely used in medicine, are mostly prepared from sulphate and perchloride of iron. These two salts produce poisonous symptoms when administered in large doses. Iron Sulphate (Ferrous Sulphate), FeSOa, 7H2O.—This is commercially known as green vitriol or copperas, and is called Kasis in Hindustani and Hir&kashi in Gujarati. It forms green monosymmetric crystals efflorescing on exposure to the atmosphere. It has a metallic astringent taste and is freely soluble in water. The official dose is 3 to 5 grains. It is used in making blue black ink and dyes. Perchloride of Iron (Ferric Chloride), Fe^Cle, 12H2O.—This is an extremely deli- quescent salt, rapidly soluble in water. When its watery solution is slowly evaporated, yellow crystals are formed. When dissolved in alcohol, it forms a non-official prepara- tion, called Tinctura fcrri perchloride (tincture of iron). The watery solution is a pharmacopceial preparation, known as Liquor Jerri perchloridi. The doses of both these preparations are five to fifteen minims. 43. Illinois Med. Jour., Dec. 1920, p. 517. 44. Jour. Amer. Med. Assoc., July 14, 1917, p. 87. 45. Ibid., Nov. 5, 1921, p, 1514. 46. Weymann, Jour. Amer. Med. Assoc., Nov. 18, 1929, p. 1367. 47. Jour. Amer. Med. Assoc., Jan. 21, 1928, p. 219, 48. Witthaus, Med. Juris, and Toxic., Vol. IV, p. 305; Berl. Jcl. Wchnschr., 1891, XXVIII, p. 466.