Reviews 



Vermont Geological Survey: Mineral Industries and Geology oj Cer- 

 tain Areas. By George H. Perkins, Ph.D., State Geologist 

 and Professor of Geology, University of Vermont. (Fourth 

 Biennial Report.) Pp. 1-227; Plates I-LXXXI. 



This report contains a description of the investigations conducted by 

 the Survey during 1903-4. The report proper is prefaced by a sketch of 

 the life and work of Charles Baker Adams, the first state geologist of Ver- 

 mont, and a list of the publications on the geology of Vermont. 



The chapter on the mineral resources of the state, by the state geologist, 

 concerns itself chiefly with the various building and ornamental stones of 

 the state. A map shows the approximate location and extent of the various 

 granite, marble, and slate areas. The nonmetallic minerals, soapstone, 

 talc, kaolin, fireclay, and asbestos, and the metallic minerals, gold, silver, 

 copper, and platinum, are briefly treated. 



C. H. Hitchcock discusses the glaciation of the Green Mountain Range. 

 It is evident from a review of the facts that all the New England and north- 

 ern New York elevations were swept over by the Hudson River lobe of the 

 Labrador glacier as it advanced down the St. Lawrence, Lake Champlain, 

 and Hudson River depressions, filling these great valleys, and spreading 

 eastward and westward over the elevated mountain districts on either side. 



W. F. Masters, in a preliminary report on a portion of the serpentine 

 belt, shows that the serpentines are largely confined to a broad belt of 

 talcose, micaceous schist. Three distinct types of rock occur — talcose 

 micaceous schist, amphibolites, and serpentine, the latter resulting from 

 the gradual alteration of the amphibolite. Serpentine occurs in two 

 localities, Lowell and Belvidere. In both places the rocks have been 

 sheared and crushed. The maximum amount of crushing and fracturing 

 occurred near the upper and lower limits of the zones, and along fault 

 planes. It is along these fracture lines that the asbestos has developed in 

 paying quantities. 



The chapter on the geology of Grand Island County, by the state 

 geologist, describes the various formations and their economic importance. 

 The county comprises Alburg peninsula, three large islands, North Hero, 

 Isle La Motte, Grand Isle, and a group of smaller islands which nearly fill 



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