BASALTIC COLUMNS. 



303 



eti alone, and subsequently the felspar and mica, either in the 

 form of mica schist, .which is composed of layers of mica and 

 quartz, or slaty rocks without fossils; these are the strata which 

 lying immediately upon the granite, and presenting marks of 

 aqueous deposition, yet partake more or less of the crystalino 

 character of the primitive rocks. During all the long period of 

 the deposition of these rocks, formed from disintegrated granite, 

 not a living thing moved, either on the dry shores or in the deep. 

 Perhaps a few animalcules existed in the clear waters, but we 

 have no distinct traces of them; all was silent, the stillness of ab- 

 solute death. During this period however, great volcanic con- 

 vulsions occurred, the yet soft masses of gneiss and_ schistose 

 slates were Upheaved, and in many cases rent open and molten 

 masses of granite and basalt flowed through. The metals, melted 

 by the intense heat, were injected into the narrow fissures, and 

 innumerable dykes and veins were formed. In some instances 

 the masses of melted trap rock have crystalized upon cooling, in 

 regular hexagonal prisms. Such are the columns which compose 

 the celebrated Fingal's Cave, exhibited in the wood-cut below. 



Directly associated with the contorted masses of mica schist to 

 which we have just alluded, there is a coarse slaty rock, exhibit- 

 ing still more clearly the marks of aqueous deposition, but by far 

 the most interesting circumstance connected with this deposit, 

 is the first appearance of animal life. We must consider with 

 no little interest, the fossil remains of these early rocks, among 



