1866.] DAWSON — ICEBERGS AND GLACIERS. 33 



COMPARISONS OF THE ICEBERGS OF BELLE-ISLE 



WITH THE GLACIERS OF 3IONT BLANC, 



WITH REFERENCE TO THE BOULDER-CLAY OF CANADA. 

 By J. W. Dawson, LL.D., F.R.S., F.G.S., Principal of McGill College. 



The snow-clad hills of Greenland send down to the sea great 

 glaciers, which in the bays and fiords of that inhospitable region, 

 form at their extremities huge cliffs of everlasting ice, and 

 annually ' calve,' as the seamen say, or give off a great progeny of 

 ice islands which, slowly drifted to the southward by the Arctic 

 current, pass along the American coast, diffusing a cold and bleak 

 atmosphere, until they melt in the warm waters of the Gulf 

 stream. Many of these bergs enter the Straits of Belle-Isle, for the 

 Arctic current clings closely to the coast, and a part of it seems 

 to be deflected into the Gulf of St. Lawrence through this passage, 

 carrying with it many large bergs. 



Mr. Vaughan, late superintendent of the Light-house at Belle- 

 Isle, has kept a register of icebergs for several years. He states 

 that for ten which enter the straits, fifty drift to the southward, 

 and that most of those which enter pass inward on the 

 north side of the island, drift toward the western end of the 

 straits, and then pass out on the south of the island, so that the 

 straits seem to be merely a sort of eddy in the course of the bergs. 

 The number in the straits varies much in different seasons of 

 the year. The greatest number are seen in spring, especially in 

 May and June ; and toward autumn and in the winter very 

 few remain. Those which remain until autumn, are reduced to 

 mere skeletons ; but if they survive until winter, they again grow 

 in dimensions, owing to the accumulations upon them of snow 

 and new ice. Those that we saw early in July were large and 

 massive in their proportions. The few that remained when we 

 returned in September, were smaller in size and cut into fantastic 

 and toppling pinnacles. Yaughan records that on the 30th of 

 May, 1858, he counted in the Straits of Belle-Isle 496 bergs, 

 the least of them sixty feet in height, some of them half a mile 

 long and two hundred feet high. Only one-eighth of the volume 

 of floating ice appears above water, and many of these great bergs 

 may thus touch the ground in a depth of thirty fathoms or more, 

 so that if we imagine four hundred of them moving up and down 



Vol. III. c No. 1. 



