I. Stratification of Snow and Formation of Glacier-Ice.
In the spring of 1866, the late Principal J. D. Forbes urged me to endeavour to find out more about the 'veined structure' of glaciers, which he then, and, I believe, until his death considered, was very much in want of elucidation. After thinking the subject over, it seemed to me that its difficulties were so considerable that it would be useless to attempt to grapple with them except in a thorough manner, and that it would be necessary to scrutinise and to follow out the gradual transition of snow into glacier-ice, from beginning to end, in at least one glacier. Superficial examination was almost worthless, for it was well known that the veined structure, or structures, existed in glacier-ice above the snow-line; and hence it appeared that the only effectual procedure would be to sink a number of pits or trenches through the superincumbent snow, commencing at the very birthplace of the glacier, and watching its growth and structural development as it descended to the lower regions. This opinion I still entertain.
I left England at the end of July, with the intention of sinking several pits in the Stock glacier, which descends towards the north-east from the Col de Valpelline.[1] In the first instance it was desirable that a trench should be made in some position that was free from local interference, and in this respect the Col de Valpelline was an excellent station. It was a snowy plateau—almost a plain (without any protruding ridges or rocks)—which gave birth to two great glaciers—one (the Stock glacier) descending gently towards the north-east, the second (the Valpelline glacier) falling away rather more rapidly to the south-west. Wretched weather and miserable workmen retarded the work, and only one pit was sunk in the time at my disposal. This was a little more than 22 feet in depth; and, although it threw scarcely any light upon the veined structure, it yielded some information respecting stratification of snow and the formation of glacier-ice. I will describe, first of all, how the work was done; and secondly, what we observed.
I arrived at Zermatt on the 30th of July, possessed of a pickaxe (one end of the head pointed and the other adze-shaped) and a couple of shovels; engaged three common peasants as labourers, and Franz Biener as guide, and waited some days for the weather to improve. On the afternoon of August 2 we started, and camped on the rocks of the Stockje,[2] at a height of about 9000 feet. It was a very gusty night, and snow fell heavily. Great avalanches poured down incessantly from the surrounding slopes into the basin of the Tiefenmatten glacier, and minor ones from the slopes of our tent. We left our camp at 9.20 a.m. on the 3d, and proceeded to the summit of the Col (11,650) against a bitterly cold wind, and with the clouds embracing everything. I marked out a place for excavation, immediately at the summit of the pass,[3] 24 feet long by 5 wide, and the men soon threw out enough snow to protect themselves from the wind. Two walls of the pit
- ↑ See map of the Valpelline, etc.
- ↑ Marked on the map of Matterhorn and its glaciers, Camp (1866).
- ↑ The pit was made about mid-way between the Tête Blanche and the nameless point marked on the Dufour map 3813 metres.
