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The upper Terrace is covered with peat, varying from two 
to eight feet in depth, in which are large roots of trees, and 
the second Terrace is also covered with peat, of about the 
same thickness. 
Section No. 2 shews the first Terrace, at a place where 
gravel is taken away for the Railway, to which it adjoins. 
The Terraces contain huge boulders of Quartz, Granite, a good 
deal of Gneiss, Laurentian Trap, and a large quantity of 
metamorphosed, supposed to be Silurian rocks, full of Mica, 
of which the mountains near are mainly composed. 
The evidence of ice action is abundant, and some of the 
large Gneiss rocks weigh fully half a ton, are polished smooth, 
with not an angle left. The Crystalline Schists are very Mica- 
ceous, often small in size, and, when water worn, assume very 
much the appearance of Celts. 
The Section No. 3 shews the Terrace at Loeh Rosque, which 
is much smaller than that of Ledgowan. 
On the sides of both Lochs are remains of Terraces varying 
from 50 to 100 feet, or even more, above the highest Section 
I have shewn, and at all levels along the mountain sides are 
enormous boulders and masses of detached rock. 
The question naturally arises—How were these Terraces 
formed, and to what period do they belong ? 
My impression is that the upper Terrace Gravels date their 
origin from the time when icebergs were floating about, tearing 
up, when they grounded, huge masses of rocks, which, on the 
re-elevation of the land, when snow was able to rest upon the 
surface of the ground, would become frozen in winter, and 
form land ice. The summers would be short, but the heat 
probably great, as is the case at the present day in Norway 
and Sweden. The ice would slide forward, carrying with it 
not only the débris which the bergs had left, but also tearing 
up the rocks on its way to the lower levels of Lochs Rosque 
and Ledgowan, and blocking up their outfall. 
The water—and, from the melting of the snow, it would 
be of far greater volume than at the present time—being 
dammed up, would naturally rise to a point to admit of its 
