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Three forms of zinc orthophosphate:manganese have been found. The a form corresponds in x-ray diffraction pattern to the published values. The luminescence is green, the peak wavelength being 5540 A. It is produced when manganese concentrations arc below 1 mole per cent, or when higher concentrations are not heated above 700~ The fl form has a red luminescence with a peak at 6380 A. This formation occurs at manganese concentrations above 1 mole per cent and firing temperatures above 800~ The -y form may be produced by additions of magnesium orthophosphate above 3 mole per cent. The emission is similar to the ~ form with a peak at 6320 A, and of somewhat lowered intensity.

Oxidizing agents attack the disulfide groups of the cystine in wool and increase the solubility of the wool in alkaline solutions. The determination of the alkalisolubility may be used as a measure of the extent to which the wool is oxidized. The method is applicaule as a control in practical processes, such as bleaching and chlorination, and offers a measure of the extent to which wool is degraded by photochemica l reactions. Data are presented which indicate a relationship between the chemical and physical degradation of wool fibers. I.n. nI.IV.

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During treatment with oxidizing agents, the disulfide sulfur in wool appears to be changed to higher states of oxidation. The exist ence of oxidation derivatives of the disulfide compounds is indicated by the alkali-solubility det ermination, the lead acetate test, b y reduction with hydrochloric acid-potassium iodide solutions, and by cystine ana lyses.The intermediate oxidation derivatives of cystine are unstable under the conditions necessary for protein hydrolysis, a nd at least one of them, cystine disulfoxide, is partially converted to cystine. The results indicate that the values obtained for the cystine content of oxidized wool may be expected to be higher than the actual cystine content since they repr esent the a mount of cystine formed from the partially oxidized cystine compounds a s well as from unoxidized cystine groups.