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glacier deepens its bed by corrasion, until there is a decided reverse 

 curve in the profile of the slope. The upper part is concave upward, 

 the lower part is a convex ridge near the rim of the channel cut by the 

 valley glacier. With decrease in abundance of snow, the slope glaciers 

 may dwindle to bowls of snow (wanner and midden), and by selective 

 erosion they may become ridge-cutting cirques. 



Glacial movement is essentially along shearing planes; these planes 

 are parallel to the great friction of the glacier bed and are for that 

 reason approximately trough-shaped. The glacier's whole movement is 

 accomplished by means of a multitude of such planes. The planes show 

 at the base and edges of the glaciers; on the average they are from one to 

 two meters apart. Thus it results that, in proportion to the total amount 

 of movement in a glacier, the shearing along each plane is very small. 

 The blue bands are due to the regelation of the shear planes after they 

 have been melted by the over-pressure or by friction. 



Ice crystals are found in two types, those precipitated from the 

 atmosphere and those formed by freezing waters. In one place a 20-cm. 

 layer of neve consisted of vertical standing prisms; they were \-i cm. 

 in diameter and 10 cm. long arranged in two layers of 10-cm. crystals. 

 In the higher parts of the snow fields, beautiful rosettes of crystals bedeck 

 the snow surfaces. The diameter of the rosettes varies from 5 to 20 cm. 



Most of the evidence of Pleistocene glaciation has been obliterated 

 by the action of insolation and frost. From floral remains there seems 

 to have been a climate warmer by 2 . 5-3 C. preceding a recent uplift 

 of about 400 feet. 



T. T. Q. 



Kanawha County. By Charles E. Krebs. West Virginia 

 Geological Survey, County Reports, 1914. Pp. 679, pis. 32, 

 figs. 14. 



County reports have been completed for about one-half the counties 

 of this state. Kanawha County is the first to be treated in a separate 

 volume and its importance is such as to justify a full report. It is among 

 the leading counties of the state in production of coal, and is rich in 

 petroleum and building-material. 



This report follows the general plan adopted in previous reports. 

 Part I treats of the historical and industrial development and physiog- 

 raphy. Part II takes up the stratigraphy in detail. About forty 

 general sections of Carboniferous outcrops are given with several times 

 that number of partial sections. 



