CLASSIFICATION. 
67 
under the ocean that the change of position took 
place. No person who reflects on the appearances 
presented in a mountainous district can believe 
that the broken and elevated beds, the peaked sum- 
mits, the impending cliffs, and the immense frag- 
ments of rocks scattered in the valleys and adja- 
cent countries, were originally created and placed 
as we now observe them. 
CHAPTER VI. 
CLASSIFICATION OF ROCKS. 
Classification : Primary, Secondary, Transition, Tertiary.— 
Classification of Conybeare and Philips. — Of De la Beche.-^ 
Primitive Kocks described. — Mr. Lyell's Views. — Hypogene. 
— Division of Primary Rocks : Granite, Syenite, Felspathic, 
&c. — Professor Hitchcock's account of Granite. — Gneiss, — 
Mica Slate. — Hornblende Rock.— Crystallme Limestone. — 
Quartz Rock. 
We have already stated that the principal divis- 
ion of rocks is into stratified and unslratified ; an- 
other is into fossiliferous and non-fossiliferous ; in- 
deed, one of the first classifications of rocks w^as 
founded on the discovery that some rocks contain 
organic remains, while others are destitute of them. 
As the lowest series of rocks with which we are 
acquainted give no evidence of the existence in 
them of eifher vegetable or animal relics, they 
were very naturally supposed to have been formed 
before the creation of things that have life, and 
were therefore called primary^ or the primitive 
class ; while those beds which contain organic re- 
mains were called secondary. In a short time, how- 
ever, it was perceived that an intermediate class 
