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Scientific Serials

1889; Nature Portfolio; Volume: 39; Issue: 1009 Linguagem: Inglês

10.1038/039429b0

1476-4687

History of Science and Natural History

The American Journal of Science, February.—Points in the geological history of the Islands Maui and Oahu, Hawaii, by James D. Dana, The subjects illustrated by the present state of these islands are: the conditions of extinct volcanoes in different stages of degradation; the origin of long lines of precipice cutting deeply through the mountains; the extent and condition of one of the largest of craters at the period of extinction, and the relation of cinder and tufa cones to the parent volcano. The accompanying plates, reduced from the recent large Government maps, show the present general features of both islands. Incidental reference is made to the late controversy on Darwin's theory of coral islands, the author declaring emphatically that no facts have hitherto been published by Mr. Murray or Mr. Guppy that prove the theory false, or set aside the arguments in its favour. Some of the facts are more in favour than opposed to it, while none do more than offer a possible alternative.-An experiment bearing upon the question of the direction and velocity of the electric current, by Edward L. Nichols and William S. Franklin. The authors, who had already independently developed a method similar to that lately described by Foeppl (Annalen der Physik und Chemié), here repeat his experiment with an apparatus capable of indicating the direction and velocity of the current, supposing it to have direction, even though that velocity were very great indeed. They show that they would have been able to detect a change of deflection due to the motion of the coil, even though the velocity of the current had been considerably in excess of one thousand million metres per second.—On the occurrence of monazite as an accessory element in rocks, by Orville A. Derby. The researches of Mr. John Gordon and Prof. Gorceix have placed beyond doubt the wide distribution of monazite in the sea and river sands of Brazil, but under circumstances that give no clue to its origin. The petrographic analyses here described have resulted in the discovery that gneiss, granite, and syenite yield, besides zircon, a certain quantity of microscopic crystals of a heavy yellow mineral apparently identical with the Bahia monazite. Recently, also, Mr. Gordon has obtained residues of zircon and monazite from the river sands at Buenos Ayres, and from gneiss and granite decomposed in situ at Cordoba in the Argentine Republic.—On the use of steam in spectrum analysis, by John Trowbridge and W. C. Sabine. These experiments show that a remarkable degree of economy in time and in waste of apparatus results from the use of a jet of steam in spectrum analysis, when the spark method of obtaining the spectra of metals is employed.—A comparison of the electric theory of light and Sir William Thomson's theory of a quasi-labile ether, by J. Willard Gibbs. A comparison is here instituted between the electric theory of light and the new theory of an elastic ether expounded by Sir William Thomson in the Philosophical Magazine for November 1888. The result of this inquiry seems to be that both theories in their extreme cases give identical results. The greater or less degree of elegance, or completeness, or perspicuity, with which these laws may be developed by different physicists should weigh nothing in favour of either theory. The elastic theory, however, is regarded as somewhat less convenient as a working hypothesis than the electric.—In this number appears Part 1 of an exhaustive monograph, with numerous illustrations, on the geology of the volcanic island of Fernando de Noronha, South-West Atlantic, by John C. Branner.