Abstract
American Journal of Science, October.—Assuming that the earth's crust rests on a layer of liquid as a floating body, Mr. Le Conte here offers an explanation of normal faults. The crust is supposed to be raised into an arch, by intumescence of the liquid, caused by steam or hydrostatic pressure; it is thus broken by long more or less parallel fissures into oblong prismatic blocks, which, on relief of the tension by escape of lava or vapour, are readjusted by gravity, in new positions. The blocks may be rectangular in section, but are more likely to be rhomboidal or wedge-shaped; giving level tables with fault cliffs (as in the plateau region) in the one case, and tilted blocks with normal faults (as in the basin region) in the other. The author considers the Sierra and Wahsatch to have been formed by lateral crushing and folding; and the region between to have been arched, broken, and readjusted, as described, in the end of the Tertiary.—Two determinations of the ratio of the electromagnetic to the electrostatic unit are furnished from the Johns Hopkins University; one made this year, by Mr. Rosa, by Maxwell's method of measuring a resistance, the other ten years ago, by Messrs. Rowland, Hall, and Fletcher, by measuring a quantity of electricity electrostatically, and then measuring it electromagnetically with a galvanometer. The former gives v = 2˙9993 x 1010) centimetres per second; the latter, 2˙9815 x 1010 centimetres. It seems certain, according to Mr. Rosa, that v is within a tenth per cent. of 300 million metres per second.—M r Long continues his account of the circular polarization of certain tartrate solutions; and his experiments point to a law that the rotation of a double tartrate may be made to approach that of a neutral tartrate of either of the metals present, by addition of a salt of that metal (the effects being apparently explained by substitution).—Mr. Eldridge proposes a new grouping and nomenclature for the middle Cretaceous in America.—There are also papers on the gustatory organs of the American hare (Mr. Tuckerman); on the output of the non-condensing engine, as a function of speed and pressure (Mr. Nipher); and on some Florida Miocene (Mr. Langdon).
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Scientific Serials. Nature 41, 46–47 (1889). https://doi.org/10.1038/041046b0
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DOI: https://doi.org/10.1038/041046b0