910 



SCIENCE. 



[N. S. Vol. XV. No. 388. 



errors -which one who had a personal famil- 

 iarity with the region under discussion would 

 have avoided. In his compilation he has not 

 only included many statements which were 

 based on unreliable authorities, but has totally 

 misinterpreted the results of such investi- 

 gators of the region as Dr. George M. Dawson. 

 It is my purpose to point out some of the 

 more glaring errors contained in this article, 

 so that they may not become current in geo- 

 graphical literature. 



The description of the northern Rockies, 

 the St. Elias and Alaskan ranges, as composed 

 of a series of volcanic peaks, hardly deserves 

 comment, especially as they are described as a 

 coastal fringe of volcanoes and compared with 

 the volcanic peaks of the Japanese and 

 Philippine Islands. A less apparent and 

 therefore more serious blunder is the grouping 

 together, as one range, of the Cascade, the St. 

 Elias and the Alaskan ranges. The recent 

 volcanoes of the Aleutian islands and the 

 Alaskan peninsula are described as a south- 

 westerly continuation of the volcanoes of the 

 St. Elias and Alaskan ranges. As a matter 

 of fact, the Alaskan range, so far as now 

 known, is an entirely distinct feature, both 

 geologically and geographically considered, 

 from the belt of volcanoes which separates the 

 Bering Sea from the Pacific ocean. The 

 southwestward extension of the St. Elias range 

 is found in the highlands of the Kenai Penin- 

 stila. 



According to Capt. Immanuel, the glaciation 

 of northwestern America was produced by an 

 ice sheet which had its source in the high 

 mountains of Greenland and moved westward 

 across the lowlands of the northern part of 

 the continent. He states that this ice sheet 

 impinged on the Rocky Mountain front, and 

 was split into two divergent glaciers, of which 

 the southern one passed southward through 

 the Columbian depression and into California, 

 while the northern descended the Yukon valley. 

 The ice sheet, during its long journey, is sup- 

 posed to have ground up the auriferous quartz 

 veins over which is passed, and their gold con- 

 tents to have been deposited in the places now 

 found in the Klondike and Nome regions. 

 This astonishing theory is credited to Dawson 



and other American investigators. It is bad 

 enough to have a statement of this nature ap- 

 pear in what purports to be a scientific article, 

 but to credit it to American geologists, es- 

 pecially to such a thorough scientific investi- 

 gator as Dawson, is the last straw. 



The author in the course of the article shows 

 himself to be as unreliable in regard to de- 

 tails as he is incapable of treating the 

 broader geographic and geologic problems. 

 For instance, he has given figures on the out- 

 put of the Nome gold fields for two years, and 

 in both cases these figures are - a million or 

 more dollars in error. For this there is no ex- 

 cuse, as official statements in regard to this 

 production are in print. 



The map of the Seward Peninsula which 

 accompanies the paper, is a reproduction of 

 one which was published in a recent report* of 

 the U. S. Geological Survey. To this map, 

 Capt. Immanuel has taken the liberty of ad- 

 ding some axes of mountain ranges of which 

 there is no mention made in the original re- 

 port. As the latter contains the results of the 

 only surveys which have been made in the 

 Seward Peninsula, it is impossible that there 

 should be any authority for making these 

 changes in the map. 



There are many other misstatements which 

 might ' be pointed out in this article, but I 

 think I have given enough to show that it is 

 an aggregation of glaring inaccuracies and 

 faulty generalizations. Had it appeared in a 

 lesser publication than Petermann's Mitteil- 

 ungen, it would not have been worthy of con- 

 sideration, but published as it was in one of 

 the leading geographical journals of the world, 

 it seemed to me that for the sake of geographic 

 science attention should be called to its 

 dilettante character. 



Alfred H. Brooks. 



volcanic dust. 



To THE Editor of Science: Analysis of 

 some mineral dust from the Martinique erup- 



* Apparently through an oversight, the report, 

 entitled 'A Reconnaissance of the Nome and ad- 

 jacent Gold Fields,' was omitted from the list of 

 authorities quoted in this article. 



