Reviews. 



The Eco?iomic Geology of the United States. By R. S. Tarr, 

 Assistant Professor of Geology at Cornell University. 8vo, 

 509 pp. Macmillan & Co., 1894. 



This volume discusses the ore deposits and other minerals and 

 rocks of commercial value found in the United States, as well as a few 

 of the foreign deposits of a similar nature. The book is divided into 

 three parts. Part I. treats of the general mineralogical, geological 

 and technical subjects more or less directly related to the various 

 mining industries. It gives, first, a chapter on "Common Rock and 

 Vein-Forming Minerals," followed by chapters on the "Rocks of the 

 Earth's Crust," the "Physical Geography and Geology of the United 

 States," the "Origin of Ore Deposits," and "Mining Terms and 

 Methods." Part 11. treats of "Metalliferous Deposits," including 

 the ores and deposits of the useful metals. Part III. treats of the 

 "Non-metallic Mineral Products," such as coal, petroleum, fertilizers, 

 building stones, etc. In addition, the volume also contains a short 

 appendix on the " Literature of Economic Geology." The object of 

 this volume, as stated by the author in the preface, is to supply the 

 pressing need of a text-book to accompany a series of lectures given by 

 him to a class of students in economic geology at Cornell University. 



The book is beautifully printed and neatly bound. The illustra- 

 tions are well reproduced, and, in fact, all of the publishers' work on 

 the book is very good and reflects credit on Macmillan & Co. The 

 book is written in good language, and the general scheme in the 

 arrangement of the subject matter is logical, but the text is deficient 

 and contains many erroneous statements. The chapters on the " Rocks 

 of the Earth's Crust" and on the "Physical Geography and Geology of 

 the United States," give a fair general idea of those subjects, although 

 even here there are a number of inaccuracies. The chapter on 

 "Common Rock and Vein-Forming Minerals" and parts II. and III. 

 of the book, treating of " Metalliferous Deposits" and " Non-Metallic 

 Mineral Products," however, relate more especially to economic geol- 



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