Titanium (Ti., A. W. 48.1) stands midway between Silicon and Tin in some of its relations; and in other respects it is closely related to Iron, Chromium, and Aluminium. The crystals proved by Sharp (who took gr. ii. of the 1st trit. daily for a week) were originally believed to be the pure metal, but were proved later to be the cyanonitrid. One symptom of the proving is remarkable: "Imperfect vision, the peculiarity being that half an object only could be seen." Another symptom, which Burnett has turned to good account in cases of sexual weakness, is "Too, early ejaculation of semen in coitus."