The mass after lixiviation, being treated with a solution of sulphate or carbonate of potash or soda, will yield chromate of potash or soda, and by the employment of sulphuric acid, the corresponding bichromates. The solutions are then filtered, to get rid of the insoluble deposits, concentrated, and crystallized. If, instead of chromate or bichromate of potash or soda, chromic acid is sought, the mass after lixiviation is treated with sulphuric acid, and the chromic acid is obtained directly without any intermediate steps. This process has the following advantages: 1. The oxidation can be effected at the ordinary temperature, thus saving expense in fuel. 2. The heavy manual labor is avoided. 3. The loss of potash and soda by volatilization and combination with the gangue is entirely avoided. 4. It is not actually necessary to use rich ores; silicious ores can be used. 5. The intimate mixture of the material before treatment being made mechanically, the puddling is avoided, and in consequence a greater proportion of the sesquioxide of chromium in the ores is utilized.--_Bull. Soc. Chem._ 5, 371. * * * * * A VIOLET COLORING MATTER FROM MORPHINE. A violet coloring matter is formed, together with other substances, by boiling for 100 hours in a reflux apparatus a mixture of morphine (seven grammes), p-nitrosodimethylaniline hydrochloride (five grammes), and alcohol (500 c.c.). The solution gradually assumes a red brown color, and a quantity of tetramethyldiamidoazobenzene separates in a crystalline state. After filtering from the latter, the alcoholic solution is evaporated to dryness, and the residue boiled with water, a deep purple colored solution being so obtained. This solution, which contains at least two coloring matters, is evaporated almost to dryness, acidulated with hydrochloric acid, and then rendered alkaline with sodium hydrate, the coloring matters being precipitated and the unchanged morphine remaining in solution. The precipitate is collected on a filter, washed with dilute sodium hydrate, dried, and extracted in the cold with amyl alcohol, which dissolves out a violet coloring matter, and leaves in the residue a blue coloring matter or mixture of coloring matters. The violet coloring matter is obtained in a pure state on evaporating the amyl alcohol. Its platinochloride has the formula PtCl_{4}.C_{25}H_{29}N_{3}O_{4}.HCl, and has the characteristic properties of the platinochlorides of the majority of alkaloids. The coloring matter, of which the free base has the formula-- (C_{6}H_{4}N(CH_{3})_{2})--N==(C_{17}H_{19}NO_{4}) forms an amorphous mass with a bronze-like luster; it is sparingly soluble in water, freely so in alcohol, its alcoholic solution being strongly dichroic; its green colored solution in concentrated sulphuric acid becomes successively blue and violet on dilution with water; it dyes silk, wool, and gun cotton, but is not fast to light.