Mineralogy and Geology of apart of Nova Scotia. 207 



lucent and vitreous. The rock has a brecciated appearance, 

 and includes masses of granite of a diflerent nature from it- 

 self. These masses appear frequently in patches of a finer 

 grain and darker color, than the surrounding granite, from 

 which they differ only in tins respect. The felspar of this 

 granite is exceedingly prone to decay, and decomposes rap- 

 idly, on the exposed surface of the rock, insomuch that large 

 quantities of angular fragments of the quartz are profusely 

 scattered around, and constitute, by this debris, the first rudi- 

 ments of the soil. The protruding angular fragments of 

 quartz give this rock a rough, forbidding aspect — and be- 

 coming loose in a few weeks, they dislodge any lichens which 

 may have clung to them for support, and thus preserve a 

 barren surface defying all vegetation. The internal struc- 

 ture of this granite is firm and compact. It has a dark ap- 

 pearance, derived from the color of the mica, which is uni- 

 formly distributed through the mass. This rock would form 

 an excellent building material, if the felspar was less prone 

 to decomposition. This forbids its use in buildings, which 

 are intended to last for a long time. We have before sug- 

 gested, that this granite was subordinate or inferior to the 

 clay slate of the South Mountains, and to all other rocks 

 discovered in the province. It here exhibits itself, protru- 

 ding through the clay slate. The line of junction was not 

 however discovered as the covering of soil and underwood, 

 concealed their union. That there does exist a point 

 of contact near this place, we cannot doubt, for a person 

 may in a few steps, pass from one formation to the other. 

 The granite exhibits no appearance of stratification, from 

 which we could estimate its direction, but there can be no 

 doubt of its age being greater than that of the clay slate, which 

 it evidently supports, throughout its whole extent. That the 

 granite is older than the clay slate, appears from its contain- 

 ing no relics of organized beings which occur in the latter, 

 and prove it to belong to the transition formation. We do 

 not however consider this granite as belonging to the oldest 

 primitive, from the absence of all those metalliferous com- 

 pounds and minerals which characterize the more ancient 

 formations — from its brecciated structure and perhaps from 

 its containing only black mica, and being in contact with 

 transition rock. It probably belongs to the third, or newest 

 granite formation of Werner. 



