DEAR MR. DONOVAN,—
In accordance with your request I lost no time in very carefully examining the leaves of the plants which you transmitted to me in sealed packets. On placing these leaves under the microscope I discerned distinct traces of a dark-greyish gritty substance, which I scraped on to a sheet of chemically pure white paper. The quantity thus collected was very small, and would hardly permit of analysis alone. I therefore adopted the following plan. I wetted the paper and the black gritty substance with muriatic acid. I then boiled the paper in two ounces of diluted muriatic acid, and by applying known tests to this acid, I proved the presence of metallic antimony, that is, sulphuret of antimony. Collecting the residuum left in the tube, I dissolved it in water, and then injecte
