No. 5.] NATURAL HISTORY SOCIETY. 295 



have been caused by the joint or successive action of water-borne 

 ice, and glaciers. In both there are the most remarkable evi- 

 dences of submergence to a great depth in the Post-pliocene age. 

 It is a remarkable illustration of the vastness of the geological 

 changes which have occurred in comparatively modern times, 

 that we should find on the mountains of the Pacific Coast and 

 those of the North Atlantic seaboard the indications of a com- 

 mon submergence, and this of very great amount. Such vicis- 

 situdes are not to be accounted for by merely local causes, but 

 by grand agencies eflecting at once a whole hemisphere or the 

 whole earth. 



In British Columbia there seems to be good evidence of the 

 submergence of the land to such an extent that sea margins occur 

 5270 feet above the level of the sea, and at various elevations 

 between this and the present sea level. In the Rocky Moun- 

 tains Mr. Dawson had previously measured the height of similar 

 terraces 4400 feet above the sea. While those great depressions 

 occurred in the Post-pliocene period, there is evidence to show 

 that in the preceding Pliocene age the land in British Columbia 

 may have been 900 feet higher than at present. On the other 

 haud, in modern times the coast would seem to have been going 

 down at a rate in some cases of as much as ten to fifteen feet in 

 a century ; while there are Indian traditions of sudden waves 

 overflowing the land, and perhaps occasioned by earthquake 

 movements. With reference to these modern changes, it should 

 be observed that British Columbia forms a part of that great 

 band of volcanic and seismic activity which extends along the 

 west coast of America, and which presents in our own time and 

 in the more recent geological periods, evidences of agencies which 

 have long slumbered on the eastern margin of the continent. 



On our own side of America, the numerous terraces so well 

 developed on the Lower St. Lawrence, mark the stages of re- 

 cession of the Post-pliocene ocean. Mr. Richardson informs me 

 that he has found one of these terraces on the west coast of New- 

 foundland, at a height of 1225 feet above the sea. On Beloeil 

 Mountain, in our own neighbourhood, we find travelled Lauren- 

 tian stones which must have been water-borne, at a height of 

 nearly 1200 feet, and if the travelled stones found by Prof. 

 Hitchcock on Mount Washington have been deposited by floating 

 ice, then the highest summits of our mountaius must have been 

 under water at the time of the greatest Post-pliocene submer- 



