The _fluoride_, TiF₃, has been obtained as an insoluble violet powder by reduction of potassium titanofluoride, K₂TiF₆, with hydrogen. From a solution it may be obtained by reduction of the same salt with zinc and hydrochloric acid, or sodium amalgam. It forms complex salts with alkali or ammonium fluoride, of which the compound (NH₄)₃TiF₆ is an example; this salt appears to be isomorphous with the analogous compounds, (NH₄)₃VF₆, (NH₄)₃CrF₆, and (NH₄)₃FeF₆. By autoxidation in the air, the solutions form fluoroxypertitanates. The complex salts appear to exist in two forms, a violet insoluble form and a green soluble modification. The _chloride_, TiCl₃, is obtained anhydrous by reduction of the tetrachloride--mercury, silver, and hydrogen being the most suitable agents. Heated in hydrogen, it breaks up, forming the tetrachloride and the dichloride; heated in air it burns, evolving the tetrachloride and leaving a residue of dioxide. In solution, in combination with alkali chlorides, and as the solid hydrate, it exists in the green and violet forms. Concentrated aqueous solutions deposit the violet hexahydrate, TiCl₃,6H₂O. If such a solution be covered with ether, and saturated at 0° with hydrogen chloride, the green modification is formed, and may be extracted by the ether; it is stable only in the presence of hydrochloric acid. In the violet form, all the chlorine is in the ionic condition, and can be removed by silver nitrate; similar determinations have not been made with the green form, but it is most probable, as in the case of the analogous chromic salts, that only part of the chlorine content can be removed by silver nitrate. Böck and Moser[451] have recently described a brown substance, obtained by the action of the silent electric discharge on a mixture of hydrogen and the vapour of titanium tetrachloride at the ordinary temperature, which they believe to be a monotropic modification of the ordinary violet trichloride; the change of this brown form to the violet form is irreversible. [451] _Monats._ 1912, ~33~, 971; 1913, ~34~, 1825. The _bromide_ and _iodide_ resemble the chloride, but are very unstable.