402 Scientific Intelligence. 



although Europe is naturally more fully treated than the other 

 lands. While one cannot expect to find in a general work of 

 this kind detailed accounts of all topics, nevertheless the space 

 given to many problems suffices to place them definitely before 

 the student; for example, the changes of level along the coast of 

 Holland and Flanders in historic times are well summarized near 

 the end of the first volume. Among the features of the work 

 that will excite much attention are the maps of the world, on 

 which the successive formations are charted, and on which lines 

 are drawn, even across the oceans, to indicate in a general way 

 the probable division of land and water in different epochs. 

 Thus it is brought forth in a striking manner, that easteim 

 South America, nearly all Africa, southern Asia, and much of 

 Australia agree in lacking marine deposits during long consecu- 

 tive periods ; they are therefore looped together and regarded 

 as parts of a great unit. Although there must be much of specu- 

 lation in such maps, as no one can know better than the author, 

 they perform a great service in giving the student a rapid sum- 

 mary of facts of distribution, to be amplified by the text. The 

 evolution of terrestrial relief is treated near the end of the third 

 volume, where among other reasons for not accepting Suess' 

 theory of horsts, a strong point is made of the long persistence of 

 littoral conditions in certain districts (as in 1ST. W. France), for 

 such persistence would not be a natural consequence of Suess' 

 views. w. m. d. 



3. Coon J3utte, Arizona, and the Canyon Diablo Meteorites. — 

 Recent papers on this subject by D. M. Babbinger and B. C. 

 Tilghman give a detailed description of the crater-like form of 

 Coon Butte, and reaffirm with confidence the hypothesis early 

 suggested that it was formed by the impact of an enormous 

 meteorite falling with something like its original planetary veloc- 

 ity.* As is well known, this region has afforded many thousand 

 masses of meteoric iron varying in weight from a thousand pounds 

 and more down to a few ounces, the total amount aggregating, it 

 is stated, more than ten tons. Further, since the gentlemen 

 above mentioned have taken possession of the property, their 

 search has revealed several thousand additional masses, aggrega- 

 ting more than a ton. The various remarkable features of the 

 iron are too well known to need to be rehearsed here, but it is 

 interesting to note that Professor J. W. Mallet has found both 

 platinum and iridium in samples of residues from solution in 

 hydrochloric acid. Besides the iron, large quantities — a ton or 

 more in weight — of magnetic oxide of iron have been found dis- 

 tributed over the surface of the rim and the surrounding plain. 

 This "iron shale" contains nickel, iridium, and platinum, and 



*The theory, advanced in 1896 by G. K. Gilbert, that "the crater, 

 although exhibiting no volcanic rock, is essentially volcanic, having been 

 produced by an explosion of steam generated by some subterranean volcanic 

 intrusion," has hitherto been generally accepted. See G. K. Gilbert, in 

 U. S. G. S., 14th Ann. Rep., I, 187, also Science, iii, 1, 1896. 



