No. 3.] SPENCER — PALAEOZOIC GEOLOGY. 153 



and more or less homogeneous, except some of the more flaggy 

 beds wlieie the crystalline calcareous matter was deposited in 

 alternating layers with the more eartliy matter. 



As many of the dark beds are colored with bituminous matter 

 some of the calcareous rocks burn to a white lime. 



By way of comp;ning the Niagara rocks in Canada, with those 

 in Ohio, I here quote several analyses of the limestones of this 

 formation in that State, as made by Profesisor Wormley. 



I. 



Calcium carbonate 85.50 



Magnesium carbonate 11.16 



Calcic & magnesic silicates. 



Alumina and iron 2.00 



Siliceous matter 2.20 



100.86 99.08 99.63 99.68 99.90 



Anahjsts of the Shdles. — As noticed before, the Niagara shales 

 are analoirous to the limestones where the calcareous matter is 

 partly replaced by argillaceous material. 



Awiljjais V. — The sample here examined was from one of the 

 most shaly layers (No 9 of the sections) of the shaly portion 

 of the formation at the "Jolly Cut," Flamilton. Under the 

 microscope the earthy matter seemed to be held together by the 

 crystalline particles of dolomite. 



Calcium carbonate 29-4 



Magnesium carbonate 23-9 



Calcium silicate -w 



Magnesium silicate / 



Ferrous oxide O-Q. 



Ferric oxide 1-6 



Alumina 150 



Silica 24-4 



99-7 



The following analysis of the Niagara shale of Ohio was made 

 by Professor Wormley : 



Calcium carbonate 3400 



Magnesium carbonate 30 87 



Calcium silicate 8-48 



Alumina and iron 8-40 



Silica 12.21 



Water (combined) 5.40 



99-36 

 Vol. X. k2 No. 3. 



