30 Canadian Record of Science. 



brownish-grey limestone, with conchoidal fracture. Ana- 

 lysis gave : 



Calcium carbonate 83.96 



Magnesium " 9.29 



Ferrous " 0.69 



Insoluble matter 6.06 



100.00 

 The stone occurs in beds from six to eighteen inches 

 thick and has been used for building purposes. 



Black Kiver Formation. 



9. From the " Eockland Quarry," on the bank of the 



Ottawa Eiver, two miles south-east of Rockland Village, 



Clarence County, Ontario. A very compact grey limestone 



containing a little carbonaceous matter. A specimen with 



specific gravity 2.704 was found to contain: 



Calcium carbonate 94.70 



Magnesium " 2.37 



Ferrous " 0.18 



Insoluble (including carbonaceous matter) 2.75 



100.00 

 This is an excellent stone both for structural purposes 

 and for making lime. It is classed here as from the Black 

 River formation, but according to Dr. Ami the beds at the 

 quarry belong in part to the Trenton, and a sharp line 

 cannot be drawn between the two formations. 



Trenton Formation? 



10. From Mount Royal Park, Montreal, a short distance 

 north-east of the Park-keeper's house. A white to grey lime- 

 stone whose crystalline texture has no doubt been induced 

 by thermal action in connection with the eruptive mass of 

 Mount Royal. A specimen of this limestone was found to 

 have a specific gravity of 2.168 and gave on analysis : 



Lime ... 42.07 



Magnesia 1.85 



Ferrous oxide 1.13 



Alumina 2.96 



Carbon dioxide 29.83 



Silica 22.1Q 



Moisture 0.06 



100.09 



