The ore was weighed after drying at 100° C. Composition of the residue insoluble in hydrochloric acid: The ore contains no metal precipitable by sulphuretted hydrogen from the hydrochloric acid solution. In the residue insoluble in hydrochloric acid, minute, bright, black crystals were detected, which were proved to contain titanium, and were supposed to be anatase. Prof. Miller of Cambridge has been able to measure certain of the angles, and found them to be identical with similar angles of anatase. The discovery of this mineral in the Cleveland ore is at least a point of considerable mineralogical interest, and may possibly furnish some additional indication of the nature of the rock from which it was derived.