56 OS GAVEL Pa Sea 
simple elevation would not fall far short of reproducing the 
glaciers. But as the result of the uplift, it is safe to count on a 
greatly increased precipitation. It appears to me evident that 
the present conservative estimated average for the higher regions 
of ten feet annually might be doubled. Of this amount one 
half, or ten feet in thickness, might melt from the surface of the 
névés during each summer (the sun finds difficulty in removing 
that amount even at present altitudes). The remaining ten feet 
might compact into one foot of ice. Were there no loss by out- 
flow and melting at the end of the glacier, the accumulation of 
one foot of ice annually would reproduce the large Salmon 
River glacier in 1500 years. 
But a large part of the ice moved outward beyond the zone 
-of accumulation and was lost by melting. This loss was partly 
compensated for by heavy snow-slides from the surrounding 
precipitous peaks; yet, with the greatest latitude, we must allow 
two or even three times as great a period as that first men- 
tioned for the accumulation of the glacier, and the attainment 
of its maximum extent. I consider 5000 years as a fair esti- 
mate, and one which is not too strongly open to criticism. By 
a lowering of the altitude to the present and consequent increased 
mildness of the climate (in other words, a restoration of present 
climatic conditions), probably about half that time or 2500 years 
would be sufficient to cause the disappearance of the glaciers, 
and give time for the repeated slight readvances which marked 
their recession. 
The preceding is intended merely as a suggestion, a hypoth- 
esis worthy of serious consideration. The demonstration of 
its reliability will depend upon external evidence of the sup- 
posed temporary uplift of these mountains. This can only be 
secured by careful geological work between this range and the 
sea, which has not yet been done. 
The importance to glacialists in general of studies on the 
localized Quaternary glaciers of limited mountain districts lies 
not so much in the contrast between their alpine features and 
the continental features of the great North American and 
