﻿270 Canadian Record of Science. 



to break or move along the lines bounding them. The 

 mineral, however, although much distorted, as in all 

 similar rocks, does not show more than traces of actual 

 granulation under the pressure to which it has been 

 subjected, and this only in a few places about the 

 immediate periphery of the grains. Approximately equal 

 amounts of green hornblende and highly pleochroic brown 

 biotite are present, the former largely altered to chlorite 

 and carbonates, and the latter in places decomposed to 

 chlorite. Both of these minerals, however, are present in 

 but small amount. A few grains of sphene and zircon are 

 also present. The rock has evidently been submitted to 

 intense pressure. 



The granite on Juniper Island has been extensively 

 quarried. The surface, where stripped for quarrying, 

 is seen to be beautifully smoothed and grooved by 

 the action of the ice, but where it has not been protected 

 by the soil covering, it is considerably weathered and 

 these evidences of glacial action are not so well displayed. 

 The rock is excellently exposed on the face of the quarry. 

 It is dark in color, owing to the dark color of the feldspar 

 rather than from the presence of bisilicates or mica, which 

 are not abundant. It does not show a gneissic structure, 

 but on the glaceated surfaces is seen to be somewhat 

 uneven in character, owing chiefly to the irregular 

 distribution through the rock of rather large and more or 

 less irregular shaped and apparently broken feldspars 

 which are dark in color, while the rest of the feldspar 

 which constitutes the greater part of the rock is red 

 in colour and is apparently in a granulated condition. In 

 places there is also, for a foot or two, a tendency to 

 parallelism among the iron magnesia constituents, a 

 structure which would seem to have resulted rather from 

 primary movements in a higlily heated rock than from 

 secondary crushing after the rock had cooled. The 

 structure resembles that described above as occurring 



