The experiments of Schroeder reported in 1889, and confirmed by clinical observations made at Schroeder's suggestion, the same year by Gram, of Copenhagen, established the value of the alkaloid theobromine, a product of the seeds ofTheobroma cacao, as a diuretic of great power, acting by direct stimulation of the renal epithelium and lacking in the unpleasant effects upon the nervous system, tinnitus, restlessness, insomnia and delirium, attributed to its homologue caffeine.Gram, after trial of many compounds, overcame the disadvantage of the insolubility of the alkaloid by forming, by combination with salicylate of sodium, a double salt, sodium-theobromine-salicylate, which should contain at least 46.5 per cent. of the theobromine (Knoll's is said to contain 48 per cent.) and to which the name diuretin has been given. The therapeutic as well as commercial value depends upon its richness in theobromine. The compound occurs in the form of a white powder,