SOME LOCAL DETAILS. IG.". 



may l)e stated in general terms that the majority are 

 U'raiiite, syenite, diorite, felsite, i)ori)liyry, (juart'/ite and 

 coarse slates, all identical in mineral character with those 

 which occur in tlie metamorphic districts of Nova Scotia 

 and Xew Brunswick, at distances of from 50 to 200 miles 

 to the south and stnith-west : though some of them may 

 liave been derived from i'a\)Q Breton on the east. It is 

 further to be observed that these boulders are most abund- 

 ant and the evidences of denudation of the Trias greatest 

 in that part of the island which is opposite the deep break 

 between the hills of Nova Scotia and New l>runswick, 

 occupied by the bay of Fundy, Chiynecto bay and the low 

 country extendi nu; thence to bale \'erte and Northumber- 

 land strait, an evidence that this boulder-drift was con- 

 nected with currents of water passing up this depression 

 from the mtli or south-west during, perhaps, the later 

 pai't of tbo Pleistocene.*' 



liesides these boulder°, however, there are others of a 

 diftereni character ; such as gneis.s, hornblende schist, 

 anorthosite and Labradorite rock, which must have been 

 derived from the Laurentian rocks of Labrador and 

 Canada, distant '2o0 miles or more, to the northward. 

 These Laurentian rocks are chiefly found on the north 

 side of the island, as if at the time of their arrival the 

 island formed a shoal, at the north side of which the ice 

 carrying the 1)oulders grounded and melted away. With 

 reference to these boulders, it is to be observed that a 

 depression of four or five hundi'ed feet would open a clear 

 passage for the arctic current entering the straits of 



* I am informed that Mr. Chalmers has discovered striae on the 

 rocks of this low isthmus, which would show the passage of heavy ice 

 through it in Pleistocene times. 



