THE CAMP-MEETING CUTTING. 681 



cutting, and they make its whole thickness, being, indeed, somewliat eroded 

 above for over 50 feet, and then sink and rise again in a smaller mound 

 before they finally disappear. The l)ottom of the sand was nowhere 

 exposed. These sands dip southward 15'^ on the east side and are nearly 

 horizontal on the west; they are marked by delicate cross-bedding, and here 

 and there layers of pebbles up to an inch in size occur. When tii'st uncov- 

 ered they were of a delicate pink color, so that I was in the habit of calling 

 them peachblow sands. They differ from every other sand in the valley 

 in being perfect beach sands. The sand is more completely sorted and 

 rounded, and the pebbles show the sjanmetrically rounded forms and satiny 

 siu-face of beach pebbles. These pebbles are often cemented by calcite, 

 a thing never seen in the Champlaiu gravels. 



The whole is now broken up by a multitude of faults and slips and in 

 places thrown into sharp zigzags like 

 a flight of stairs. It is not, however, 

 molded into the complex curves seen 

 in the more clayey sands above, Avhich "^fe, ^' '^^ 



we shall see to have been independ- ^ 

 ently and at a later time subjected to a 

 similar crushing. The surface of the 



sands rises with an easy even slope Fi8.4o,_Block of frozen •■innks.aud," showing fine sys- 



J 1 tem ot joints. Tho horizontal lines are the bedding of 



and sinks with the same smooth lines "«'8'""1- The vertical .ire strongly marked joint planes. 



Tho block wa.s 15 inches square. 



below one's sight. A curious appear- 

 ance shown (fig. 45) by a frozen block of the sand may even be due to the 

 develoinnent by the weight of the ice mass, or by torsion in connection with 

 its thrust, of a latent pressure cleavage. A frozen l)lock from the iioi'th end 

 of the east opening of the sands had carved out upon it by the wind a series 

 of perfectly parallel cracks, 3 to 4°"" apart and about at right angles to the 

 bedding, and these, together with the bedding, had beeii very beautifully 

 dissected out by the wind. 



The sands here dip southward, and the ice coming from the north had 

 ridden over the upturned edges of the lamina^ so that the plane of these 

 fissures was at right angles to the direction of the thrust of the ice. I have 

 little doubt that the ice moved over this sand bed Avhile it was frozen, and 

 that this is the reason why the sands are so often and so sharply faulted and 

 broken and not thrown into twisted, contorted folds, as happened later to 



