128 THE ICE A(iE IN CANADA. 



surfaces, and sweep it downward, laden with uprooted 

 trees, timber, stones and j^ravel. The destruction of roads, 

 bridges, and otlier property, and the tearing up and bury- 

 ing under rid)bish of meadows, are sometimes terrific. 

 Fortunately, such freshets occur only at long intervals, 

 but the loss and injury which they cause are long 

 remembered, and tlie ridges and niounds of (Ubris wliich 

 tliey deposit remain as nu;mentoes of their destructive 

 power. Logan lias well described* the annual breaking 

 up, or " siiove," of the ice on the 8t. Lawrence, whicli, 

 though a comparatively ipiiet phenomenon, piles up ridges 

 of stone where the Hoes of ice ground. In the Pleistocene 

 period, sucli ice-freshets and shoves must have been 

 frequent, and it is not uidikely that some of the gravel 

 deposits whicii are credited to the melting of the 

 continental glacier are due to their agency. 



4.-B0RDAGE ICE. 



4. A s[)ecial ice agency of some importance is that In 

 wliich ^Ir. Chalmers has directed attention on the coast 

 of the bay des Clialeurs.-f- 



Mr. Cbalmers describes the rocks of various paleozoic 

 periods, along the south side of the bay des Chaleurs, as 

 presenting a somewhat flat and even surface to a height 

 of 50 to 75 feet above the sea level. A similar appearance 

 is presented by the beds below the sea level along the 

 coasts. He connects this with the action of floating ice, 

 now very evident in the bay. In winter a fixed border 

 of ice is formed along the coast, from two to six feet thick, 

 and extending from the shore for a distance of from half 

 a mile to several miles. Tlie open portion of tiie bay is 

 generally full of loose floes. 



* Journal Geol. Society. 



t Canadian Record of Science. 



