The oxidation of solutions of stannous chloride was first studied extensively by Young1 who found that the reaction was somewhat dependent upon the acidity of the solution, highly sensitive to the action of certain catalysts such as copper and iron salts, and further, was inhibited by some of the alkaloids and certain other substances. The reaction was also studied by Miyamoto,2 who determined the effect of acid concentration, the rate of bubbling of the oxygen, and several other factors.It has been shown by many investigators that autoxidations are catalyzed by the presence of certain metallic ions, notably by those of copper, iron, manganese, cobalt, and nickel. This investigation was originally undertaken with the object of finding out whether or not a mixture of these ions exhibit promoter action in the case of autoxidations. Since no cases of promoter action were found, certain physical and chemical conditions affecting the autoxidation of stannous and cuprous chlorides have been studied.Reagents: In most cases no special precautions were taken to further purify the reagents inasmuch as very pure reagents were available. The stock solutions of stannous chloride were made by dissolving a weighed amount of the salt in air-free distilled water containing enough hydrochloric acid to prevent the precipitation of any of the basic chlorides of tin. These solutions were kept under an atmosphere of hydrogen.Apparatus: The apparatus used in these experiments was essentially the same as that used by Walton.3 This apparatus consists of a burette and leveling tube connected to a reaction flask by means of capillary glass tubing. The reaction flask was clamped in a vertical position and by means of an appropriate mechanism, it was rotated back and forth around the vertical axis.The only deviation from the original apparatus was in the shape of the reaction flask (Fig. i). The bottom of a 150 cc. round bottom Pyrex flask was heated in such a way that a narrow band, extending to within an inch of the end of the neck on either side and parallel to the vertical axis, was softened. This softened portion was then pressed in by the edge of an iron spatula so that a fissure about one-half inch deep was formed. A second fissure was made in a plane at right angles to the first. When shaken, the ridge on the inside of the flask breaks the surface of the liquid and in this way drives the liquid into the gaseous phase and drives the gas into the liquid phase.Method of Procedure: The concentration of acid in the stannous chloride solution was determined by titration of a measured sample with standard

The precipitation of zinc sulfide from sulfate-hydrosulfate solutions has been studied. The precipitation was found to be complete to less than 0.25 mg. out of 257 mg. at a hydrogen-ion concentration as high as 2.5 X 10-2. Nickel, iron, manganese, chromium and aluminum may be separated quantitatively from zinc by this sulfide precipitation, but cobalt cannot be so separated. High chloride-ion concentration increases the solubility of the zinc sulfide. A procedure is outlined for the quantitative precipitation of zinc and its separation from the other metals. Methods of igniting the precipitate have been studied. The temperature should be closely controlled at 500°when igniting the zinc sulfate, and at 900°w hen igniting the sulfate to oxide.

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ABW5ACTA coMpact feeding console designed for storing, preparing, and dispensing food ites= in a space vehicle has been evaluated during a siulaeted 3-man, 14-day apace flight. The engineering design of the cosole and accessories were evaluated and the acceptability and nutritional value of the food recommended for use in the console were measuzed. Further research must be conducted to. improve the designs incorporated in the console, Design should be compatible with the diet and type of processed food to be furnished the orewumebers,