I. ELIMINATION OF MERCURY DURING TREATMENT The outcome of acute poisoning with mercury bichloride depends chiefly on the amount of mercury absorbed. Prompt emesis is therefore the most efficient treatment.1 This should be supplemented as soon as possible with copious gastric lavage. Further elimination of the mercury has been sought by repeating the gastric lavage through the subsequent days, by extensive colonic irrigations and by pushing the consumption of fluids to secure diuresis. Local cleansing is a part of the therapeutic intent, but the expected removal of mercury generally has a large share in inciting the prescribing of these measures. As there are apparently no data on how effectively this object is accomplished and on how much mercury is really removed by such treatment, it appeared worth while to undertake these studies. They include the quantitative determination of mercury, by the method described by Booth2 and ourselves, in