REFERENCES. [1] GOADBY, K. W.: Journal of Hygiene, vol. ix., No. 1, 1909. [2] GOADBY, K. W., AND GOODBODY: The Lancet, vol. ii., p. 988, 1909. [3] GOADBY, K. W.: Report of the Committee on Lead, etc., in Potteries, vol. iii., p. 478, 1910. [4] MOORE: Private communication. [5] ARMIT: Journal of Hygiene, vol. viii., No. 5, 1908. [6] STRAUB: Berl. Med. Woch., p. 1469, 1911. [7] LEHMANN: Archiv für Hygiene, vol. xxxiv., p. 321, 1899. CHAPTER VII SYMPTOMATOLOGY AND DIAGNOSIS =Acute Poisoning.=--Acute poisoning by lead is not common. Industrially it hardly ever occurs. Zinn[1] states that, out of 200 cases of industrial lead poisoning in his clinic in Berlin, only one was to be regarded as an acute case. In most instances the poisoning is due to swallowing some compound of lead, either as an abortifacient or to commit suicide. The pathology and symptoms of such acute lead poisoning depend in the first place upon the nature of the salt of lead swallowed, as, for instance, after swallowing sugar of lead a burning taste is complained of, with acute gastric pain, generally coming on within an hour of taking the poison, salivation, metallic taste in the mouth, acute hiccough, and griping pain in the abdomen. The mouth is stained a whitish-grey. Later there is a great fall in blood-pressure, the skin becomes moist, or a cold sweat may appear. The respiration and pulse drop; finally comes vertigo, acute headache, coldness of the extremities, anæsthesia, and death in one or two days, or the case passes on to one of chronic poisoning. If the patient survives for the first two or three days, retinal changes frequently make their appearance, and occasionally acute fever may supervene. Various paralyses also appear, and the case then becomes one of subacute or chronic poisoning. The lethal dose for healthy adults is probably as large as 50 grammes for lead acetate, for lead carbonate 25 grammes; these doses are, of course, only approximate. Post mortem in a case of acute lead poisoning by ingestion, the mouth and stomach show the presence of a lead salt in the mucous exudation, together with corrosive gastritis and considerable swelling and œdema of the mucous membrane. The large intestine is generally stained darkly, from a light brown to a deepish black; this staining may not appear until quite low down in the intestine. There is hyperæmia of the liver, much engorgement of the vessels in the mesentery, the kidney, and the brain. The rest of the intestinal viscera show signs of engorgement. Fluid may be present in the peritoneal cavity, and occasionally in the other serous cavities. The histological examination of the various organs exhibits the same microscopical hæmorrhages as are found in the cases of chronic poisoning to be described later.