This paper presents the results of a thoroughly unorthodox approach to the synthetic rubber problem. In developing their new butyl rubber, the Esso Laboratories have turned to simple olefins rather than diolefins or more complicated chemical derivatives as the main raw material.

Its formation is in no way connected with that of allantoin or carbonyldi-urea. It may be formed by the alkaline oxidation of allantoin, especially a t high temperature and in neutral solution; by the action of alkali alone upon carbonyl-di-urea; or finally (with the best yield) by the action of hydrogen peroxide in acid solution upon the compound C4H606N3. V.-It has not been proved possible to trace any parallel between the 1V.-The formation of cyanuric acid is in all cases seconday. action of hydrogen CAMBRIDGX, Xlfiiss. [CONTRIBUTION FROM ALLANTOXANIC peroxide upon uric acid and that of permanganate. THE ORGANIC LABORATORY OF THE MASSACHUSETTS INSTITUTE OF TECHNOMGY.] ACID AS AN OXIDATION PRODUCT OF URIC ACID.

Judging from the above observations, it seems likely that nature makes use of comparatively few basal coloring substances with which to produce many different colors by means of slight chemical changes. These substances are generally acid, sometimes neutral in character, and generally change color in acids and alkalies, alternately, acting as indicators. It is noticeable also that many of them are very sensitive to the action of light and air. The faintly colored alcoholic solutions of the Rose or the Perennial Pea, when evaporated to dryness, leave the bright red colored substance. The pink blossoms of the Perennial Pea, when picked and allowed to wilt, change to a violet color. The whole subject of natural coloring matters deserves a careful study from the chemical standpoint.Manhattan, Kansas.