Geology and Natural History. 263 



with other inaccuracies in the experiment. — Phil. Mag., Jan., 

 1909, pp. 190-192. J. t. 



10. Permanent Magnetism of Copper. — J. G. Gray and A. D. 

 Ross have studied the behavior of pure copper in strong mag- 

 netic fields under various conditions of temperature varying from 

 bright red heat to that of liquid air. The traces of remanent 

 magnetism are recorded. Ordinary and electrotytic copper were 

 investigated together with the traces of iron. — Physikal. Zeit- 

 schrift, Jan. 15, 1909, pp. 59-61. J. t. 



11. United States Magnetic Tables and Magnetic Charts, for 

 1905 ; by L. A. Bauer. Pp. 154, 1 figure, 7 charts. Washing- 

 ton, 1908 (Department of Commerce and Labor, Coast and Geo- 

 detic Survey). — The latest results obtained for the magnetic 

 elements of the United States and the immediately adjacent 

 countries are presented together in this volume, which appears 

 independently instead of being attached as an appendix to the 

 reports of the Coast and Geodetic Survey. The author states 

 that he resigned his position in connection with the survey on 

 September 1, 1906, but that the matter was essentially complete 

 at that date except as regards the determination of the correc- 

 tions for secular variation. In order that these may be as accu- 

 rate as possible, the charts now issued are made out for January 

 1, 1905, instead of a subsequent date, as for 1910.* Recent 

 experience has shown that unexpected changes have taken place 

 in the variation and that they have not progressed in accordance 

 with the predictions from the empirical formulae established 

 earlier, hence the necessity of great care to insure accuracy. The 

 number of stations in the country for which the magnetic ele- 

 ments are tabulated. is 3311 (2869 C. and G. Survey Stations),. or, 

 in other words, there is one magnetic station for about 973 square 

 miles. Furthermore, magnetic work at sea was begun on Coast 

 Survey vessels in 1903, so that the results obtained by them from 

 1903 to 1907, as well as by the Carnegie Institution along the 

 Pacific coast, have been available for this work. In addition to 

 the various tables, the report includes seven charts giving the 

 declination, inclination, horizontal intensity, vertical intensity, 

 total intensity, also the magnetic meridians, and, finally, the secu- 

 lar motion curves and horizontal intensity secular variation curves. 



II. Geology and Natural History. 



1. Die Fossilen Insekten and die Phylogenie der Pezenten 

 Formen ; von Anton Handlirsch. In nine parts, pp. 1430, 

 many plates and text-figures. Leipzig, 1906-08 (Wm, Engel- 

 mann). — This monumental work reviewing 7640 species of fossil 

 insects is now completed. (An earlier review appeared in April, 

 1907, of this Journal.) On pages 1142-1 192 is given a summary of 

 the paleontologic results, a chapter of the greatest interest not only 



* It is proposed that the magnetic charts of the Carnegie Institution, with 

 which Dr. Bauer is now connected, be also referred to the same period. 



