96 BELT ON THE GLACIAL PERIOD IN NORTH AMERICA. 



of two himdred and forty-five feet, and lower down still at Matan 

 river they have not been found much higher than fifty feet above the 

 sea. I do not suppose that these shells mark the extreme heights 

 to Avhich the sea has reached at the different places, but so far as the 

 observations go, they show a decrease of the submergence towards 

 the mouth of the Gulf. I am not acquainted with the drift-beds 

 of the Province of Nev/ Brunsvdck, but I have no doubt that they 

 will be found to bear out the same inference, namely, that going 

 eastward from Montreal the elevation of the marine beds marking 

 the former submez'gence of the land gradually decreases, until in 

 Nova Scotia it reaches zero. 



The gold washings of the valley of the Chaudiere within the area 

 that we know, which from the evidence of sea shells was submerged 

 after the glacial period, show us what would have been found in the 

 auriferous districts of Nova Scotia, if that Province had also been 

 submerged. The absence of gold washings in Nova Scotia and their 

 presence in Lower Canada, are strictly in unison with the absence 

 of marine deposits Avith sea shells in the one district and their pre- 

 sence in the other. 



XL— OEIGIN 0? TflE GLACIAL PERIOD. 



1. Tlieojies of origin. — It is far beyond the scoj^e of this paper to 

 enter upon the discussion, or even to give an account of the various 

 theories that have been advanced in explanation of the origin of the 

 glacial period. It is less necessary for me to do so as the whole 

 question is quite a modern one, and the views of Croll, Frankland 

 and others have been so recently made public, that the scientific 

 world is well acquainted with them and with the objections that 

 have been urged against them. I will therefore confine myself to 

 the consideration of the one that seems to me the most satisfactory 



Sir Chas. Lyell in his admirable Principles of Geology long ago 

 showed that the extremes of heat and cold might be produced by 

 the grouping of the land ; in the one case, about the equator, and 

 in the other, about the poles. There can be no doubt that a rise of 

 polar and a submergence of tropical and sub-tropiral lands, would 

 greatly lower the temperature of the arctic and temperate zones. 



That during the glacial period or part of it, the land now glaci- 

 ated stood somewhat higher than at present, has been inferred from 



