Mineralogy and Geology of Nova Scotia. 315 
tains, rendering the ore at Clement’s, in their immediate vicinity, 
strongly magnetic by driving off a portion of its oxygen; while that 
at Pictou, more remotely situated, was not sensibly affected by 
its influence, but retains its full quantity of oxygen, is compara- 
tively light, and is without magnetism. Besides, by this  theo- 
ry we are enabled to account for the existence of so large a 
quantity of carbonate of lime in the latter ore, the heat not having 
been sufficient to drive off the carbonic acid from the fossil shells 
contained in it. The superior compactness of the former, its great- 
er specific gravity, and more intimate union with the adjoining 
slate, from which, in many places, it is difficult to discover any 
line of separation, are in confirmation of the theory which we 
venture to offer, thus supported, to the consideration of our read- 
ers ; assured as we are, that should any of them be induced to pass 
over the same ground, and examine for themselves the evidences 
on which it is founded, they would not be disposed to differ much 
from us, if indeed they were not fully brought over to the same 
views. It affords new proof of the igneous origin of the trap 
rocks on which it wholly depends; and it is thus, we think, by 
amalgamating the rival theories of Werner and Hutton, that just 
conclusions can be formed, of the geological nature of this coun- 
try, and the relation which the rocks of aqueous deposition bear 
to those of igneous origin. 
The clay-slate forming the banks of Bear river, near its 
mouth, contains beds of iron pyrites, of a compact, amorphous 
character, well suited for the manufacture of copperas. In fact, 
where this mineral is freely exposed to air and moisture, the sul- 
phate of iron forms spontaneously, and covers this rock with an 
efflorescent incrustation. ‘The hepatic variety also occurs with 
it, and, extending through the rock to some distance from the 
