REPORT OF THE DIRECTOR AND STATE GEOLOGIST 1900 r29 



These sands are up on the main watershed of the region, the 

 lakes being the sources of the principal streams. There are no 

 present streams which could have laid them down, and their 

 source must therefore be sought in glacial streams which no 

 longer exist. Thej can not have been deposited by lakes, un- 

 aided by streams, since the action of lakes on shores of glacial 

 material is to wash away the sand and mud out into the lake and 

 form gravelly or cobbly shores, such as those of Big Tupper lake. 

 The sands away from the heart of the region are easy of expla- 

 nation. They are along the present streams, and were laid down 

 by them in aggrading their valleys, when overloaded with mate- 

 rial, shortly after the ice retreat, probably aided by temporary 

 ice dams, or, still lower down, were pushed out as delta deposits 

 by these same streams in the higher levels of the bodies of stand- 

 ing water which occupied the St Lawrence and Champlain valleys 

 in the closing stages of the glacial period. But the high level 

 sands in the lake belt were transported by streams which no 

 longer exist. 



In the writer's opinion these sands were probably deposited as 

 deltas in a large and irregular, shallow lake formed back of the 

 ice tongue which occupied the lake belt during its slow retreat 

 north, the material being furnished by the subglacial and en- 

 glacial streams flowing into the lake at the ice margin. The 

 massing of the sands in the north half of the belt, north of the 

 watershed, indicates this. This remains as the only one of sev- 

 eral working hypotheses that suggested themselves, which it has 

 not been necessary to abandon for some reason or other; and no 

 other hypothesis has suggested itself. The basin of Upper Sar- 

 anae lake is thought to have been occupied by an ice tongue 

 which, lingering longest where it was thickest, prevented the 

 washing of sand into the hollow while the streams spread it out 

 along the sides of the ice tongue. A majority of the hollows in 

 which the other ponds lie would seem to have a similar origin, 

 that is, blocks of ice were left stranded during the general ice 

 retreat, the sands were washed over and around them^ and then 

 the slow melting away of the ice left the hollow in which the 



