

STRATIFIED ROCKS. 



29 



IL 



LIF E%; 



ton. 



1 ft 



■ °m tt 



the indentations being, I believe, due to the fact that, while 

 these gravels were still incoherent over great areas, the upper 

 parts of the new red series, the lias, and perhaps other 

 newer strata, were piled upon them, and the vertical pres- 

 sure consequent on this vast superincumbent pile, induced 

 a lateral pressure in the loose-lying pebbles of the conglo- 

 merate ; so that being squeezed, not only downwards, but 



ones incoh outwar ds, they ground on each other, and partly by the aid 



of intervening grains of sand, circular indentations were 

 formed sometimes an inch in diameter." (Ramsay, Geological 



stones fra Journal, Feb. 1855, p. 200.) Some of them are fractured 



and re-cemented. The fractures were produced by pres- 

 This coi sure, generally close to faults. 



nglomerafe 



I sandstone 



nd roundel 



is. 



shire. 



i 



dec! intl: 

 ith tt 



n TV 



aierate is i 

 r lime, fl 

 have gene 



Lestone, a 

 relief 



ROCKS. 



m 



Wall-cases &© to 44u 



These contain suites of Specimens intended to illustrate the 

 lithological characters of stratified rocks ; or, in other words, 



om 



■j-kefl! the nature of the stony substances of which stratified rocks 



. 140 to 1* 



are formed. 



They are therefore not arranged in their 



stratigraphical order of succession, but rather according to 



i0 their various compositions, shewing in "Wall-CaSGS ^bl 



& 43 how rocks of various kinds pass by insensible 



e 



to co 







8 



crat* 



of ^ 



gradations into each other. 



£> 



Wall-case 4©. 



Nos. 1 to 32 chiefly consist of Specimens illustrating the 

 manner in which depositions of carbonate of lime (lime- 

 stone) are formed from a bi-carbonate of lime in solution 

 in water. All rain water contains carbonic acid, which 



Upper 

 Gallery. 



Wall-cases 

 40 to U. 



