GLEN ROY, IN SCOTLAND. 
G9 
pian range on the northern side of Strathmore 
valley occupies the same position in reference 
to that of the Sidlaw Hills opposite, as does 
the range of the Alps to that of the Jura, 
while the intervening valley may be compared 
to the plain of Switzerland. As from the 
Bernese Oberland and from the valleys of the 
Reuss and Limmath gigantic glaciers came 
down and stretched across the plain of Swit¬ 
zerland to the Jura, scattering their erratic 
boulders over its summit and upon its slopes 
at the time of their greater extension, and, as 
they withdrew into the higher Alpine valleys, 
leaving them along their retreating track at 
the foot of the Jura and over the whole plain, 
so did the glaciers from Glen Prossen and 
parallel valleys on the Grampian Mountains 
extend across the valley of Strathmore, drop¬ 
ping their boulders not only on the slopes and 
along the base of the Sidlaw Hills, but scatter¬ 
ing them in their retreat throughout the valley, 
until they were themselves reduced to isolated 
glaciers in the higher valleys. At the same 
time other glaciers came down from the heights 
of Schihallion on the west, and, descending 
through the valley of the Tay, joined the 
