Note 79 — A CYCLOPÆDIA OF PRACTICAL RECEIPTS, PROCESSES, AND COLLATERAL INFORMATION (continued 10)

Animal tissues and liquids containing organic matter are best prepared for testing for arsenic by Marsh’s test, in the following manner proposed by Odling:—The tissue, or the residue obtained by the evaporation of a liquid over a water-bath, is to be thoroughly dried at a temperature of about 212° F., then ground to powder or cut up into small pieces, next drenched with the strongest hydrochloric acid and allowed to stand twenty-four hours in a warm place, and finally distilled. The distillate will contain arsenic (if it existed in the material under examination) comparatively free from organic matter, and is, therefore, in a fit state to be introduced into Marsh’s apparatus, as the organic matter, which is the cause of frothing, has been removed.