308 R. BELL — GLACIAL PHENOMENA IN CANADA. 



ice at any locality varies to a great extent with its latitude, so that 1 1 » * - an- 

 tiquity of the glacial groovings and drift deposits of the district between 

 Pennsylvania and Nebraska in the south and those of the latitude of the 

 center of Hudson's bay in the uorth may and probably does differ by many 

 thousands of years. In order to attempt some kind of calculation of time 

 based on a given rate of recession of the ice-sheet for this distance, let us for 

 the moment Bet aside all other questions that might complicate the problem 

 and try to obtain some idea as to bow long it might take li>r the simple and 

 direct recession of the ice, say from the Latitude of Cincinnati to that of the 

 most southern glaciers of Baffinland. Cincinnati is in latitude 39° and the 

 reputed glaciers of Baffioland in about 65°, a difference of twenty-six degr< 

 If the average retreat of the ice sheet was as rapid as one degree in a thou- 

 sand years, which is probably above the mark, it would require 26,000 years 

 to need'' from its southern limits to the regions where the glacial condition 

 is possible at this day. 



On Portland promontory on the east coast of Hudson's hay, in latitude 

 3 , and southward the high rocky hills arc completely glaciated and hare. 

 The striae arc as fresh-looking as if the ice had left them only yesterday. 

 When the sun hursts upon these hills alter they have been we1 by the rain 

 they glitter and shine like the tinned roofeof the city of Montreal. Yet even 

 here it must have been a good many thousand years since the glaciers dis- 

 appeared. 



In my report for 1884 I described the occurrence of the handiwork of the 

 Eskimos on Outer Diggee island, indicating a lapse of at least one thousand 

 years: and still the time which has gone by since these people built their 

 dwellings and their .-tone fish-traps on the beaches then washed by the sea, 

 but now ehvated seventy or eighty feet above it> level, must have been 

 short compared with the days when great ice-sheets from the interior slid 

 down the rocky slopes on the foot of which these beaches lie. 



The nee.— ion and disappearance of the ice-sheet is, bowever, only one of 

 the elements to be taken into account in trying to arrive at some estimate 

 of the time which bas elapsed since the deposition of the till along its south- 

 ern extension. We have to consider the submergence and elevation of the 

 land which followed. These movements are extremely bIow, and would re- 

 quire at leas! double the above time, or over 50,000 vears, for their accom- 

 plishment. At Naelivak. on the eastern coast of Labrador, raised beaches 

 .-how with great distinctness at an elevation of aboul 1,500 feet above the 

 -. ;i. The land might have been 2,000 feet higher than at present at the time 

 of the greatest accumulation of ice. This would represent a depression oi 

 3,500 feet and a subsequent elevation of 1,500 feet. If the rate of vertical 

 movement w<\>- as rapid as -even feel pi r century, the depression aud eleva- 

 tion proved by the existence of these beaches would require upwards of 



