Extracts from the Minute Book of the Geological Society . 601 
the ice at the height of at least forty feet above the level of the 
river, as it stood where we observed it. There being but little 
depth of water in any part of the river’s passage over the flat beds 
of limestone, these on the breaking up of the river obstruct the 
passage of the ice from bank to bank ; which being thus collected 
in large masses, dams the water up. When the ice gives way, the 
water instantly subsides, leaving the banks covered with a thick 
wall of ice, which it requires the greater part of the summer to 
dissolve. 
Eight miles above the limestone fall is a portage forty yards in 
length, over flat rocks of a very solid and hard texture, of a greyish 
brown colour. This rock now forms the bed of the river, and we 
no longer observe the slightest trace of limestone among the 
boulder-stones along the shore. Below the portage the limestone 
rises to the height of about ten or twelve feet above the level of 
the river, and consists of plates that are from two to twenty inches 
thick.* 
As we ascend, the bank Contains more sand and gravel with a 
* Tbe specimens No. 17717 and 17718, Coll. Geol. Soc. brought by Mr. Kerney from 
this part of Nelson river, consist of black flint, much resembling the flint obtained from 
our chalk pits. 
“ The same kind of limestone,” observes Mr. Auld, “is also found in Churchill river, 
at the distance of about fifty-six miles from the sea, extending along that river more than 
twenty-five miles, and rising at last for twelve miles together to the height of sixty or 
seventy feet above the water, while the bed of the river is composed of the same hard 
brown rock that we find in Nelson river. The same limestone is also found in that branch 
of Hayes’s river which is called the Shemataway, where it is of great height, and is 
covered as in Churchill river, with only a thin coating of soil. It is seen again in various 
places upon Severn river, being first observed at the distance of about thirty miles from 
the sea, and extending throughout the distance of above fifty more, but in no place rising 
more than fifteen or eighteen feet above the water. The natives say that the same kind 
of stone appears in the rivers between the Albany and the Severn. At Martin’s fall, upon 
Albany river, below Gloucester house, the same rock is said to be found not in strata but 
in mass, and to be a white one, much lighter in colour than the stratified rock upon the 
Shemataway. Upon the Seal river, which I ascended eighteen years ago, I only remember 
that the banks adjoining two rapids were composed of laminated stone.” 
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