LETTER XXVI.
Geneva.
There are five or six different Glaciers, which all terminate upon one side of the Valley of Chamouni, within the space of about five leagues.
These are prodigious collections of snow and ice, formed in the intervals or hollows, between the mountains that bound the side of the valley near which Mount Blanc stands.
The snow in those hollows being screened from the influence of the sun, the heat of summer can dissolve only a certain portion of it. These magazines of ice and snow are not formed by what falls directly from the heavens into the intervals. They are supplied by the snow which falls during winter on the loftiest parts of Mont Blanc; large beds or strata of which slide down imperceptibly by their own gravity, and finding no resistance at these intervals, they form long irregular roots around all the adjacent mountains.
Five of these enter, by five different embouchures, into the valley of Chamouni, and are called Glaciers, on one of which we had been.
At present their surface is from a thousand, or two thousand feet high, above the valley.
Their breadth depends on the wideness of the interval between the mountains in which they are formed.