REVIEWS Ts70)) 
composition, classification, formation, and alteration of minerals, as 
well as the principles and methods of blowpipe analysis. Appendices 
contain lists of minerals arranged according to their principal constitu- 
ents and to their mode of crystallization, a list of reference books, and 
an abbreviated “‘key to the determination of minerals.” The key is a 
device which classifies minerals according to*luster, streak, color, and 
hardness and gives merely the pages in the main part of the text, where 
the detailed descriptions of the minerals may be found. 
Perhaps the most noticeable defect is the paucity of photographs 
(less than forty), which probably accounts for the low price of the work. 
However, there are numerous drawings which remedy this deficiency to 
a large extent. 
Minerals are classified according to their chemical composition. 
The arrangement of the silicates, a most difficult problem, is especially 
worthy of favorable comment. The book should be of great value as a 
text for advanced work in descriptive mineralogy. 
De Jey 
Detailed Report on Webster County. By D.B. REGER, West Virginia 
Geological Survey, Morgantown, W.Va. 1920. 671-+xvi 
pages, 35 halftone plates, and 24 zinc etchings in the text, ac- 
companied by a separate case of topographic and geologic maps. 
Price, including case of maps, charges prepaid, $3.00. Extra 
copies of topographic map, 75 cents, of the geologic map, $1.00. 
Webster County contains the northward extension of the famous 
New River Coal group, as also the Kanawha group and the lower mem- 
bers of the Allegheny Series in its northern portion. 
