MIDDLE DISTRICT OF SCOTLAND. 6^7 



1. Conglomerate. This rock, which is com- 

 posed of roundish, and sometimes angular masses 

 of various kinds and sizes, imbedded in a basis or 

 ground, occurs in beds varying in thickness from 

 a few feet to several hundred yards. It is dis- 

 tinctly stratified, and the strata, although general- 

 ly horizontal, yet are occasionally much inclined, 

 even sometimes nearly vertical. The beds of con- 

 glomerate are generally conformable with those 

 of the red sandstone, and sometimes unconform- 

 able, the nearly horizontal beds of conglomerate 

 resting upon pretty highly inclined strata of sand- 

 stone, and these horizontal beds being again cover- 

 ed with inclined strata of sandstone. It alternates 

 with, and frequently passes into, the red sandstone. 

 Sometimes, small granular conglomerate is con- 

 tained in the coarse, in the form of . roundish 

 balls or concretions, from three to five feet in 

 diameter. These remarkable concretions at first 

 sight, might be confounded with the rounded 

 balls of granite, ivliich are imbedded in the con- 

 glomerate. 



The roundish and angular masses of which the 

 conglomerate is chiefly composed, vary in size from 

 that of a few inches to several yards in diameter. 

 They are of different rocks and minerals. Thus, 

 at Craw town, a few miles from Stonehaven, por* 

 phyry is the predominating imbedded rock, and 

 , is associated with granite, gneiss, quartz, &c. At 

 JBervie, the most abundant piasses are of quartz 



