665-666) describes the plant-like structures obtained by introduction of a crystal of a soluble salt of certain metals into a solution obtained by mixing I volume of sodium silicate (water glass, specific gravity approximately 1.4) with 3 or 4 volumes of distilled water. The color of the structure varies with the cation, being white with lead, magnesium, zinc, and aluminium, bright yellow with uranyl, green with nickel, purplish blue with cobalt, greenish blue with bivalent copper, reddish brown with ferric iron, white changing to green with ferrous iron, and white changing to light brown with bivalent manganese.
J. S. H.
Quinine Hydrobromide with Trihalogenmethane of Crystallization.--W. SCHNELLBACH AND JOSEPH ROSIN (Jr. Am. Pharm. Asso.
1932 ' XXI, ioo9-IOI2 ) have obtained two crystalline compounds of quinine hydrobromide; the one contains two and one-half molecules of chloroform of crystallization, the other two molecules of bromoform of crystallization.
J. S. H.
Carbon Monoxide Content of Gas.--MAx TRUMPER (Int. Clinics, 1932, [42] iii, 221-225) states that natural gas contains no carbon monoxide while manufactured gas may contain from 2o to 30 percent. or even more, carbon monoxide. The lethal dose of carbon monoxide may be less than I gram; inhalation of air containing o.4 per cent. carbon monoxide for I hour may produce death. Addition of natural gas to manufactured gas decreases the carbon monoxide content, lessens the toxicity, and increases the heating or fuel value per cubic foot.
J. S. H.
Chlorine Disinfectants.--A. C, FAY (Agric. Exp. Station, Kansas State Coll. Agric. and App. Science, Circular I6O, 1-8, 1931) describes the preparation and use of solutions of calcium hypochlorite and sodium hypochlorite for disinfection in the dairy industry. The disinfectant solution pumped through pipelines, vats, etc. should still contain at least 5o parts per million of available chlorine as it leaves the last piece of apparatus. The available chlorine (parts per million) content of the solution used for sub-