Abstract
American Journal of Science, May.—Studies of Eocene mammalia in the Marsh collection, Peabody Museum, by J. L. Wortman.—On the velocity of chemical reactions, by W. Duane. A description of two physical methods for following the velocity of a chemical change occurring in solution. In one of these the solution to be studied is placed in a wedge-shaped hollow prism and compensated with a similar wedge, the chemical change being followed photographically. A diagram is given showing the inversion of sugar as followed by this method. In the second method the change of volume of the solution is followed in a large thermometer.—The transmission of sound through porous materials, by F. L Tufts—On a yoke with intercepted magnetic circuit for measuring hysteresis, by z. Crook. A description of a new form of yoke possessing certain advantages over the ordinary types. It gives practically a perfect hysteresis cycle, and can be used for studying the demagnetising action of electric currents without interrupting the magnetic circuit or varying it by means of a solenoid.—Mineralogical notes, by C. H. Warren. Crystallographic measurements and chemical analyses of anorthite crystals from Franklin Furnace, felspar crystals from Raven Hill, Colorado, iron wolframite from Dakota, and pseudomorphs of wolframite after scheelite from Trumbull, Conn.—On the expansion of certain metals at high temperatures, by L. Holborn and A. L. Day. Bars of metal 500 millimeters long were used, and enclosed in a porcelain tube heated electrically. The temperatures were measured with the thermocouple and ranged from 250° C. up to 1000° C. in the case of platinum, and in other cases to as high a temperature as the properties of the metal under examination would permit. Results are given for platinum, palladium, silver, nickel, constantan, wrought iron and steel.
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Scientific Serials . Nature 64, 92–93 (1901). https://doi.org/10.1038/064092b0
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DOI: https://doi.org/10.1038/064092b0