7^ OBSERVATIONS 



thofe materials ; or whether it were not rather a body tranf- 

 fufed from the fubterraneous regions, and made to break and 

 invade the ftrata, in the manner of our whinftone or trapp, 

 and of porphyries, into which the whinftone often graduates. 



It was not that I doubted of there being fuch a thing as ftfa- 

 tified granite ; the granit feuillete or granit veine, which M. de 

 Saussure has defcribed in his Voyages dans les Alpes, is cer- 

 tainly a ftratified granite ; and this is very well diftinguilhed 

 by that author, as is the granit en maffe, the hiftory of which 

 we are now enquiring after. I had alfo fpecimens of a fimilar 

 veined granite from the North-weft Highlands, that is, from 

 beyond Fort William and the lakes ; and this veined granite is 

 ftratified along with the quartzy, micaceous and Alpine ftrata. 



But my object was to know if the granite that is found in 

 mafTes has been made to flow in the bowels of the earth, in like 

 manner as thofe great bodies of our whinftone and porphyry, 

 which may be confidered as fubterranean lavas. Now, this 

 queftion could only be determined by the examination of that 

 fpecies of granite upon the fpot, or where it is to be found in 

 immediate connection with thofe bodies which are evidently 

 ftratified ; bodies, confequently, whofe natural hiftory we have 

 fome means of tracing. 



In ftratified bodies, we have not only the means of diftin- 

 guifhing thofe which, in point of time or fucceflion of opera- 

 tion, have been formed prior and pofterior, we may alfo, with 

 regard to the manner of operation, diftinguifh thofe ftratified 

 bodies from others which had been introduced among them in 

 a forcible manner, or with marks of violence inconfiftent with 

 the regular procefs of ftratification. Now, the evidence of this 

 muft be found in the broken, feparated and diftorted parts of 

 thofe regularly formed bodies, the natural hiftory of which we 

 fo far know. 



This was the queftion, with regard to granite, that I wanted 

 to have refolved by means of the connection of that mafs with 



the 



