صور الصفحة
PDF
النشر الإلكتروني

THE LIBRARY
OF THE

UNIVERSITY OF ILLINOIS

[graphic]

Snow bed longitudinal

section.

Snow bed transverse

[blocks in formation]

Section

[graphic]

I would here observe, that in this climate, where we are subject to periodical rains, persons should be cautious in concluding that piles of rocks in long lines are moraines, even though their edges, are in no way water-worn. On both of these rivers I saw many instances of such heaps of rocks, which might very easily have been thought moraines ; and though from their immense extent, and the great size of the blocks they contain it is not easy to believe that they have been formed by the action of water, more particularly as the rocks have perfectly sharp edges and as there is often no appearance of water ever having been near them; yet they have certainly been brought down by torrents and may be easily traced up to ravines in the mountains.

The term snow-bed having been hitherto applied by travellers in these mountains, (with one exception†) both to true glaciers, and to mere beds of unaltered snow. I will shortly explain what is meant by it when used in the latter, which is the correct sense. In many parts of the higher valleys, real beds of snow lie far below the limit of perpetual snow for the greater part of the year, and some would probably be permanent at very low elevations were they not destroyed by the rain during the rainy season. These snow beds are formed by avalanches, as is sufficiently proved by their form and position. Figs. 6, 7 and 8, represents one on the Kuphinee river, which occurs at an elevation of about 10,800 feet.

per

It came down from a ravine, and entirely covered the river which flowed under its whole length. The snow extended but little beyond the upside of the ravine, but was prolonged far down the river on the lower side. Its surface was marked by curved hills, as is shown in the sketch. This is evidently precisely the form that would be assumed by snow falling down the ravine into the river. The slope of the river bed being great, the avalanche would naturally continue its course down it, after having filled the channel immediately in front of the ravine. The fall of an avalanche in the upper part of this valley gave me an opportunity of seeing the motion of loose snow in large masses; it was very similar to that of a fluid body, the snow appeared rather to flow than to fall. So here, the snow descending through the raviue, gradually filled the river channel; the main supply moving with the greatest * I allude to Major Madden, who has given a short account of the glacier of the Pindur in a late number (176) of this Journal.

velocity down the middle, but sending off, all along it as it went on, particles to the sides. Its head would therefore advance in a convex curve, as the central particles moving directly forward, would always keep in advance of those that spread out to the sides. The end of the snow bed thus takes the curved form shown in the figure, and a succession of smaller avalanches, would mark its surface with numerous curves of the same sort.

In the last two miles of the approach to the Kuphinee glacier, we crossed two snow-beds, both of which were upwards of of a mile wide, and extended from the ravines in which they originated, right across the valley from side to side, entirely covering up the river.

The surface of many of the snow-beds has a sort of rippled appearance, caused by the protection given by grass and leaves blown upon the snow to the parts immediately under them. The snow itself is generally firm, and receives but a slight impression from the foot of a man walking over it.

I have estimated the heights of these glaciers from observations of the boiling point of water as follows; the results will certainly be within 500 feet of the truth.

Ft. above the sea.

12,000

..

12,000

Lowest point of the glacier of the Pindurand source of the river 11,300
Surface of the glacier at the commencement of smooth ice...
Lowest point of the glacier of the Kuphinee and source of
the river
Surface of the glacier at the commencement of smooth ice ... 13,500
Diwalee, union of the Pindur and Kuphinee.

8,200

The limit of perpetual snow here being about 15,000 feet above the sea, in the one case the glacier comes down 3700, and in the other 3000 feet below it. At the Kuphinee glacier, a mass of Rhododendron companulatum, a shrub 6 or 8 feet high, was growing within 30 yards of the ice. There were no shrubs of any size at the Pindur glacier, but grass and flowers were at both places flourishing considerably above the level of the ice.

Having now concluded the record of my own observations on the two glaciers seen by myself, I will add two extracts from the Journals of travellers in these mountains, which most clearly prove the existence of two other glaciers, both of great size, one at the source of the Bha

giruttee or Ganges, the other at that of the Gorce, which is one of the main feeders of the Kalee or Gogra. The first extract is from a journal, by Capt. Hodgson, of a visit to the source of the Ganges, in the year 1817. (Asiatic Researches, No. XIV. Qu. pp. 117-128. Capt. Hodgson thus describes the first appearance of the glacier from which the rivers rises.

"The Bhagiruttee or Ganges issues from under a very low arch at the foot of the grand snow-bed,"—" over the debouche the mass of snow is perfectly perpendicular, and from the bed of the stream to the summit we estimate the thickness at little less than 300 feet of solid frozen snow, probably the accumulation of ages;-it is in layers of some feet thick, each seemingly the remains of a fall of a separate year. The height of the arch of snow is only sufficient to let the stream flow under it."

[ocr errors]

He ascends the glacier-" This vast collection of snow is about 1 miles in width, filling up the whole space between the feet of the peaks to the right and left; we can see its surface forward to the extent of 4 or 5 miles or more". general acclivity 7°, but we pass small hollows in the snow caused by its irregular subsiding; a very dangerous place, the snow stuck full of rubbish and rocks imbedded in it. Many rents in the snow appear to have been recently made, their sides shrinking and falling in.” Ponds of water form in the bottom of these."

66

"It was remarked above, that the snow of the great bed was stuck, as it were, with rock and rubbish, in such a manner, as that the stones and large pieces of rock are supported in the snow and sink as it sinks; as they are at such a distance from the peaks as to preclude the idea that they could have rolled down to their present places, except their sharp points had been covered, it appears most likely" that they came down like snow balls with avalanches. "It is not easy to account for the deep rents which intersect this snow-bed, without supposing it to be full of hollow places." The source of the Ganges is stated by Capt. Hodgson to be 12,914 feet above the sea.

The next is an extract from a journal of Lieut. Weller, printed as a note to a journal of Capt. Manson's, Journal Asiatic Society, No. 132.

"I went to see the source of the Goree river, about a mile N. W. from Milum. The river comes out in a small but impetuous stream, at the foot of apparently a mass of dirt and gravel some 300 feet high,

« السابقةمتابعة »