156 Scientific Intelligence. 



1908 (received late in 1907). — Passarge, known for bis thorough 

 explorations of the Kalahari region of South Africa as reported 

 in a large volume entitled Die Kalahari (Berlin, 1904), has now, 

 while acting as professor of geography in the University of 

 Breslau, prepared a more popular account of the region of his 

 travels, from which one may obtain a comprehensive understand- 

 ing of its geology, land forms and climate, flora, fauna, natives 

 and European colonists. The book is of special value to the 

 scientific geographer — as distinguished from the narrating trav- 

 eller — in that it places constantly in the foreground the depend- 

 ence of various phenomena on the nature of the land. w. m. d. 



11. The Production of Gold and Silver in 1906 • by W. 

 LiisTDGREN and others. Pp. 265. — This is' one of the chapters 

 from the Mineral Resources of the United States for 1 906, pub- 

 lished by the Geological Survey, which are issued in advance of 

 the completed volume, the appearance of which is now promised 

 within a few weeks. It is shown that the production of gold in 

 the United States has increased from $36,000,000 in 1880 to 

 upwards of $94,000,000 in 1906. Between 1880 and 1894, the 

 amount produced varied but a few million dollars ; in 1895, 

 however, it jumped up to $46,000,000, and since then the pro- 

 gress has been almost uninterruptedly upward. In regard to 

 silver, the production during the same period and also the price 

 per ounce have varied widely, the . total value varying from less 

 than 830,000,000 (in 1902 and 1903) to upwards of $57,000,000 

 (in 1890 and 1891). The amount for 1906 is a little in excess of 

 $38,000,000, while in 1880 it was nearly $35,000,000. 



Another chapter from the same volume, by David T. Day, is 

 devoted to the production of platinum ; it states that the amount 

 produced in the United States has risen from 100 troy ounces in 

 1880 to 1439 ounces in 1906, the latter valued at $45,189. 

 During the past year or two, as is generally known, the market 

 price has varied widely, the minimum given for 1907 being $26 

 and the maximum $41 per ounce. 



12. Origin of Meteor Crater {Coon Butte) Arizona / by H. 

 L. Fairchild. Bull. Geol. Soc. America, vol. xviii, pp. 493-504. — 

 The interesting phenomena presented by the remarkable crater- 

 like pit in Arizona, with which is associated the occurrence of 

 the Canyon Diablo meteorites, are discussed again in this paper. 

 The conclusion reached is summarized as follows : "All the 

 phenomena thus far found in the long and careful exploration of 

 the crater, the distribution of the wreckage both inside and out- 

 side, and the composition and structure of the materials, seem to 

 be fully and satisfactorily explained on the theory of impact by 

 a celestial bolide of high velocity, and do not fit any other 

 theory." 



The author urges the propriety of calling the crater Meteor 

 Crater, instead of Coon Mountain, or Coon Butte, — names 

 which have formerly been employed. A series of plates give 

 excellent views of the crater as seen from within and without. 



