204 REVIEWS 
washing the pay-streaks the heavy minerals garnet and magnetite are 
concentrated along with the gold. ‘The first forms ‘‘ruby sand” and 
the latter “black sand.”’ 
Good prospects for gold occur in many other places in the Seaward 
peninsula. ‘The geographic portions of some of the different local- 
ities suggest that they may belong to the same gold belt. The facts 
known to us, however, are not sufficient to prove this; and it must 
simply be regarded as a working hypothesis. Should subsequent 
development and investigation show that the gold of all of these districts 
of Seward peninsula is derived from the same series of rocks, this gold- 
mining region will embrace an area of at least 5000 to 6000 square 
miles. If this proves to be the case, it does not by any means follow 
that the entire belt will contain workable gold deposits. We should 
rather expect to find the gold confined to certain zones within the belt.” 
The report is accompanied by a number of excellent views of the 
region. This preliminary report gives us a good idea of just what the 
visitors and prospectors may expect when they reach the Cape Nome 
region. Scientists will await the appearance of the final report with 
interest. Ca Rev keewns: 
Syllabus of Economic Geology. By JouN C. BRANNER, Ph.D., and 
Joun F. Newsom, A.M., Second Edition, 1900, pp. 368. 
Plates and Diagrams. 
This volume is a syllabus of a course of lectures on economic 
geology given by the authors at Leland Stanford Junior University. 
It is intended primarily for the student, but will also be found a most 
valuable guide to anyone interested in the various branches of economic 
geology. It begins with a general list of the more important works on 
economic geology, and of the periodicals relating to this subject. After 
this are a few introductory remarks on geology in its relation to various 
economic subjects, including mining, agriculture, forestry, manufac- 
turing, industries, art, roads, railways, migration, etc., followed by a 
brief synopsis of geological sections, maps, surveys, etc., from an 
economic standpoint; a summary of economic geological products and 
their various classifications as proposed by different authors; rock- 
cavities ; the formation of ore bodies; and the features of ore deposits. 
This general part of the subject takes up the first fifty pages, and most 
of the rest of the volume treats of different kinds of ore deposits and 
