Abstract
Americcen Jouernal of Science, April.—The absolute wavelength of fight, by Lonis Bell. The final results are here given of the research partially reported in the Journal for March 1886. Owing to the wide discrepancies in the value of this constant as determined by various observers and methods, the author gives a brief historical summary of the subject, with a critical discussion of the standards of length, methods, and apparatus employed in the present investigation. The details of the experimental work, together with some remarks on the final results, and some questions of theoretical and practical interest connected with the work of recent experimenters in this field, are reserved for a future number.—History of the changes in the Mount Loa craters; Part 1, Kilauea (continued), by James D Dana. Here are discussed questions connected with the ascensive action in the conduit lavas, the effects of heat, the hydrostatic and other gravitational pressure.—The electromotive force of magnetization, by Edward L. Nichols and William S. Franklin. At the Ann Arbor meeting of the American Association fot the Advancement of Science the authors described some singular modifications in the relation of iron to acids which occur when the reaction takes place within the magnetic field. In the present paper, which was read at the New York meeting of the Association in 1887, they deal with the behaviour of iron when that metal acts as one electrode in a voltaic circuit, and is at the same time subjected to magnetization.—Notes on certain rare copper minerals from Utah, by W. F. Hillebrand. A series of rare copper ores, including olivenite, erinite, tyrolite(?), chalcophyllite, clinoclasite, mixite(?), and bronchantite, are here subjected to careful chemical and physical examination.—The Taconic system of Emmons, and the use of the name Taconic in geological nomenclature (continued), by Chas. D. Walcott. The main subject of this paper is the geology of the Taconic area as known to Dr. Emmous, with a comparison of its area as now known. As a result of this comparative study, the author finds that the Lower Taconic is essentially a repetition of the Lower Silurian (Ordovician) of the Champlain Valley, while the Upper Taconic appears to be conformably subjacent to the Stockbridge Limestone of the Lower Taconic, and to include the Potsdam horizon at or near its upper portion.—Three formations of the Middle Atlantic Slope (continued), by W. J. McGee. This paper is occupied with the Appomattox formation, its character, and distribution.—W. Le Conte Stevens describes a new lecture apparatus of an extremely simple character for the demonstration of reflection and refraction phenomena.
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Scientific Serials . Nature 37, 623 (1888). https://doi.org/10.1038/037623a0
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DOI: https://doi.org/10.1038/037623a0