Abstract
American Journal of Science, June.—Prof. Elias Loomis: a memorial address prepared by H. A. Newton at the request of the President and Fellows of Yale College.—The magnetic field in the Jefferson Physical Laboratory, Part II., by R. W. Willson. In the February number of the Journal the author gave some observations of the variations of the horizontal intensity in different parts of the Jefferson Physical Laboratory in 1886-87, and upon the disturbance in the magnetic field produced by the presence of iron steam pipes and other iron masses. He now finds from extended observations that brickwork produces a great disturbance of the magnetic field, and thinks, therefore, that in general it would be safer to make exclusive use of wood for buildings and piers intended for refined magnetic measurements.—The electrical resistance of the alloys of ferro-manganese and copper (from determinations made by Mr. B. H. Blood), by Edward L. Nichols. The observations show that ferro-manganese-copper alloys decrease in electrical re sistance each time they are subjected to a change of temperature. In one case an alloy containing 80˙82 per cent, of copper and 19˙12 per cent, of ferro-manganese, was hard drawn in the pro cess of obtaining a strip suitable for measurement. Its specific resistance at 20°, referred to pure copper as unity, was 30˙38; this resistance gradually diminished as the strip was repeatedly heated to 100° and cooled to 20°, until after seven such heatings it had fallen to 30˙072. The effect of successive annealings upon the resistance of a number of alloys is also described. —Fluid volume and its relation to pressure and temperature, by C. Barus. The paper contains the introductory part of a series of experiments on the compressibility of liquids, in progress at the Physical Laboratory of the U.S. Geological Survey. Taking the results from 0° to 185° as a whole, it follows that if with the observed thermal expansion compressibility be supposed to increase inversely as the first power of the pressure binomial (A + p, where A is constant), then temperature and pressure must vary linearly to maintain constancy of volume.—On hamlinite, a new rhombohedral mineral from the herderite locality at Stoneham, Mi., by W. E. Hidden and S. L. Pen- field.—On a large spring-balance electrometer for measuring (before an audience) specific inductive capacities and potentials, by Alfred M. Mayer. The chief characteristic of the excellent piece of apparatus described is that it shows directly, and not inferentially, that different dielectrics transmit the force of electricity in different degrees.—Notice of new Tertiary mammals, by O. C. Marsh.
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Scientific Serials. Nature 42, 260–261 (1890). https://doi.org/10.1038/042260b0
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DOI: https://doi.org/10.1038/042260b0