238 AN ENQUIRY INTO THE [Ch. XII. 



of a similar nature, but which are not fissile ; and do these 

 mutually interfere with each other, under every possible form 

 and position ? So, likewise, the regular layers of granite are 

 similarly situated with respect to the more irregular concre- 

 tions of the same rock. The president of the Geological 

 Society, after having enumerated various appearances sup- 

 posed to be characteristic of unstratified rocks, has recorded 

 his conviction that the distinction is arbitrary and unsatis- 

 factory. " Let us grant," says he, " all those properties 

 attributed to the unstratified rocks : does the conclusion of 

 the Huttonians follow from these premises ? or, is there any 

 one of these properties which may not equally be found 

 among rocks that are stratified ? " * 



It must not, however, be omitted to mention, that Lyell 

 attaches some importance to another character, as indicative 

 of the primary slates being stratified. "The resemblance 

 between these rocks and the sedimentary deposits," he ob- 

 serves, " is often carried farther ; for, in the crystalline series, 

 we find beds composed of a great number of layers placed 

 diagonally, as we have shown to be the case in the crag and 

 other formations." 



This resemblance may be admitted, but it cannot be 

 allowed as evidence of the stratification of the primary slates, 

 unless this species of structure be clearly demonstrated to 

 have proceeded from the action of water. This point is con- 

 tended for by Lyell f at some length, but his arguments have 

 failed to convince us, and we shall, therefore, in as few words 

 as possible, state our objections. 



These inclined layers dip at various angles from 30 to 4=5 : 

 on the Suffolk coast they generally dip towards the south ; 

 but, in some instances, in opposite directions in the upper and 

 under part of the same deposit, with the intervention of a 

 horizontal layer. The Professor has supposed that these 

 layers have been formed by deposition from water on inclined 



* First Principles of Geology, p. 267. 

 f Principles of Geology, vol. iii. p. 176. 



