Abstract
American Journal of Science, December 1895.—How to find the key-note of auditoriums, by E. Cutter. If a speaker uses the key-note of his auditorium, the audience shows by attitude and attention that it hears what is said. The speaker speaks with ease, and feels his voice impinge upon the farthest walls. The key-note may be found by means of a siren, or by singing, and observing which note resounds most powerfully. The paper contains practical hints of some value to public speakers, but is unscientific in tone and substance.—Stratigraphy of the Kansas coal-measures, by Erasmus Haworth. The different formations lie one above the other in regular order, similar to the order found in other parts of the world. The general character of the shales throughout the whole of the coalmeasures is such that they must have been deposited, in the main, in shallow water, probably ocean-water, as evidenced by the frequency of ripple-marks and other physical properties. The coastal area must have progressed westward as geological time advanced. The thickness of the Kansas coal-measures cannot be much less than 2500 feet.—Igneous rocks of Yogo Peak, Montana, by W. H. Weed and L. V. Pirsson. Yogo Peak is composed of a core or stock of massive, granular, igneous rock, composed chiefly of augite and orthoclase. The mass shows a progressive differentiation along its east and west axis, with a continual increase in the ferromagnesian elements over the felspathic ones.—A new alkali mineral, by Warren M. Foote. This mineral, named Northupite, after its discoverer, crystallises in regular octahedra, whose diameters rarely reach I centimetre. It is brittle, shows uneven fracture, and a hard ness of 3˙5 to 4. In powdering the mineral a fœtid odour is distinctly perceptible. It is easily fusible before the blowpipe, and its analysis indicates it to be a double chloride and carbonate of sodium and magnesium, with traces of phosphoric acid, silica, iron, calcium, and organic matter. It was found in the neighbourhood of the Borax Lake, California.—On the affinities and classification of the Dinosaurian reptiles, by O. C. Marsh. Twelve restorations of Dinosaurs are given, and a relation is traced between them and the Crocodilians.
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Scientific Serials. Nature 53, 262 (1896). https://doi.org/10.1038/053262a0
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DOI: https://doi.org/10.1038/053262a0