Method of Extraction from the Stomach.—Dry the contents of the stomach or portions of the liver, etc., and incinerate in a porcelain crucible. Treat the ash with nitric acid, dry, and dissolve in water. The solution of nitrate of lead may now have the proper tests applied.
Tests.—Sulphuretted hydrogen gives a black precipitate; liquor potassæ, white precipitate; sulphuric acid, white precipitate, insoluble in nitric acid; iodide of potassium, a bright yellow precipitate. A delicate test for lead in water is to stir the water, concentrated or not, with a glass rod dipped in ammonium sulphide: a brown coloration is produced. One-tenth of a grain of lead in a gallon of water may be detected.
Chronic lead-poisoning is an 'industrial disease,' and, being an occupation risk, its victims are entitled to compensation at the hands of their employers. In case of death, compensation has been awarded even when at the autopsy the patient has been found to have suffered from acute tuberculosis of the lungs. The responsibility of apportioning the monetary value of disablement resulting from the action of the lead rests with a judge or jury, who are guided by the expert medical evidence available.
Diachylon, or lead-plaster, is largely used as an abortifacient.
XXV.—COPPER AND ITS PREPARATIONS
Poisoning with copper salts is rare. The most important are the sulphate, subacetate, and arsenite.
Sulphate of Copper (bluestone, blue vitriol) in half-ounce doses is a powerful irritant. Has been given to procure abortion.
Subacetate of Copper (verdegris) occurs in masses, or as a greenish powder. Powerful, astringent, metallic taste. Half-ounce doses have proved fatal.
Symptoms.—Epigastric pain, vomiting of bluish or greenish matter, diarrhœa. Dyspnœa, depression, cold extremities, headache, purple line round the gums. Jaundice is common. A chronic form of poisoning may occur, with symptoms closely resembling those of lead.