REVIEWS 201 
throughout the volume, detracts greatly from the value they would 
otherwise possess. Too much is left to be inferred, and there is 
always a strong liability of error in the putting together of scattered 
observations from various localities which the reader is obliged to do 
for himself in order to obtain an intelligent understanding of the 
questions treated. 
It is proposed in the next volume of the Final Report (Vol. V), 
nearly half of which is already in type, to take up the systematic 
geology of the state, and many of the details, upon which are based 
the extensive changes of classification and the new conclusions regard- 
ing the problems of archean geology, are reserved for publication in 
this volume. It seems better, therefore, to reserve any extended criti- 
cism of the proposed changes until the full facts upon which they are 
based are published. M. L. FULLER. 
The Ore Deposits of the United States and Canada. By JAMES 
F. Kemp, New York, 1900, 3d edition, rewritten and enlarged. 
xxiv-+ 481 pp. 163 illustrations. 
It is with pleasure that geologists will welcome the new edition of 
Professor Kemp’s work on ore deposits. It is to be noticed that the 
revision has been so complete and the additions so numerous as to bring 
the matter up to the date of publication and make it one of the most 
valuable works of its kind in this country. 
Professor Kemp has undertaken a difficult task in endeavoring to 
embody in a single volume a serviceable text-book and a work of ref- 
erence. That he has succeeded is shown in the first instance by its 
increased use in the colleges and in the second by a perusal of its 
pages. 
The general plan of the work remains about the same as in the 
former editions. The matter is divided into two parts, the first o 
which treats of the general features of ore deposits, the underlying 
geological principles, the minerals important as ores, the gangue 
minerals, and their sources, the structural features of veins, the filling 
of veins, and the classification of ore deposits. This part of the work 
would have additional value, especially to the prospector and engineer, 
if it were illustrated a little more fully by diagrams. It is true the 
number of illustrations has been increased from. 94 to 163, but there is 
