RED PRIMARY SANDSTONE. 339 



and the jasper, in particular, seems to be invari- 

 ably worn by attrition. 



The prevailing tints are varieties of red, but 

 they are more particularly detailed in the sy- 

 nopsis. 



SYNOPSIS OF PRIMARY SANDSTONE. 



i 

 FIRST DIVISION. 



Simple : apparently of quartz only. 



A. Granular. 



a. Coarse grained. 



b. Fine grained, passing to compact. 



B. Compact, the fracture rough, but the grains 

 scarcely distinguishable : passes into quartz. 



C. Splintery in the fracture; passing into the 

 granular, and also into the compact : some of the va- 

 rieties have an aspect much resembling that of compact 

 felspar. 



The colours are various, but modifications of 

 red are predominant. These are, pink, bright 

 brick red, brown red, purple red : it also occurs 

 of a pale grey, of a lead blue, of an ochre yellow, 



z 2 



