986 
Glaciers. 
Subterrane- 
ous glacier 
of Tselitz. 
Origin and 
formation of 
the glaciers, 
of the proprietor, The entrance of the cavern was co- 
vered up with a wall, and the ice has not formed so ra- 
pidly since that time. The glacier and cavern of Tse- 
litz is in a very lofty rock in the Carpathian mountains. 
Its mouth is large, its width is 26 fathoms, and it pene- _ 
trates to a depth of 50 fathoms, advancing still farther 
by a rough and winding passage. When the snow, 
which clothes the mountain in winter, begins to melt in 
spring, it filters through the rocks, and falls in drops, 
which are instantly frozen, and which form pyramids of 
ice both in the roof and.on the floor of the.cavern. The 
cavern is thus lined with ice, sparkling like the most 
brilliant crystals. 
carts. would fiot be able to carry off this ice in a week. 
At the approach of autumn the ice begins to melt; and 
at the beginning of winter the air is mild, the earth dry, 
‘and not a vestige of ice is to be seen. 
Tt’was long the opinion of the vulgar, and even of 
some intelligent writers, that the glaciers increased from 
below ; and M. ‘Altmann was the first who maintained 
their true origin, although he erroneously supposed that 
‘the pyramids of ice-rose from the glacier itself. In or- 
der to explain the origin of glaciers, let us suppose that 
all the lofty mountains and peaks which surround the 
Glacier de Bois have been covered with snow during 
winter. At the approach of spring, the snow at low al- 
titudes, and at the place where the glacier itself exists, 
is completely melted by the influence of -the sun and 
the rains. At a greater altitude, varying with the lati- 
tude of the place, and with local circumstances, the snow 
is only partly melted, and having, therefore, imbibed a 
* great quantity of water, it is frozen into a mass of im- 
Progressive 
descent of 
the glaciers. 
perfect ice during the succeeding winter. A fresh fall 
‘of snow covers these frozen spaces, and is in its turn 
converted into imperfect ice. In this way, the ice is 
‘accumulated during every succeeding winter, till the 
equilibrium ‘of the mass is destroyed, either by its own 
magnitude, or ‘by other causes, and the whole is preci+ 
rem in the form of an avalanche into the valley be- 
ow. The snow which falls in still higher regions, lies in 
tranquillity on the level summits, or the hollow cavities 
of the mountain ; but that which falls upon the decli- 
vities is easily loosened by any sudden thaw, and falling 
down, it adds either to the accumulated ice below, or 
passes directly to the bed of the glacier. The ice thus 
collected from the surrounding heights, will experience 
articular changes in its new situation. It is now sub- 
ject to the action of the sun and the rain, which will 
wear down the high and angular masses into pyramidal 
and other shapes ; and the water -will fall down the 
chasms, and give a particular transparency to their sides. 
At the lower extremity of the glacier towards the plain, 
the greatest changes will take place. The fall of the 
exterior masses will be followed by the advance of those 
behind them, and a movement will thus be propagated 
throughout the whole glacier. 
From these causes, the glaciers will progressively de- 
scend to the plains below; and the rapidity of their mo- 
tion will depend upon the inclination of the bed -on 
which they rest, and on the magnitude and velocity of 
the reinforcements which they receive from fresh avalan- 
ches. The stream which flows from the extremity of 
the glacier, forms in general a vault of ice above, which 
adually widens as the ice melts, and when it can no 
onger sustain the superincumbent mass, it is crushed 
by its own weight, and gives place to the masses behind 
it. This progressive motion of the glaciers, is rendered 
visible by the variation in the position of large stones on 
the surface, or of trees frozen in the ice. In the glacier 
GLACIERS. 
M. Bel informs us, that six hundred ~ 
little stream which runs below the glacier. 
may necessarily 
they advance more spidly 
fore encroach upon the cultivated plains. Their aug- 
mentation commonly takes place in spring, and when 
they have made great inroads upon the lower 
they are generally found to diminish for some years af- 
terwards a eyes 
We have already had occasion to mention both the ont 
masses of granite rock, which lie upon the surface b 
of the glacier, and the heaps of enormous stones, c¢al- 
led the Moraine, or Murren, which are accumulated at '"' 
its lower extremity. These stones sometimes are to- poop 
tally different from those in the valley where they now g) 
lie, and must have been detached from rocks often 
six or eight leagues distant. These stones are frequent- 
ly accumulated in separate mounds like hil or 
graves, and arranged in parallel lines of a considerable _ 
height and width. These are generally called Gouffres 
lynes,and appear on a great scale in the glacier of Rosbo- 
en on the Simplon. Sometimes a large regular pyra- 
mid of ice is seen, with a huge stone upon its summit: 
The heaps of stones which we have mentioned, contain 
in,general specimens of the rocks in the higher regions 
of the mountains. : Oe oe 
It has been already stated, that the glaciers are com 9, 
roe of different kinds of ice. Some of it is granu- ,.. 
ated and imperfectly frozen, other parts have a transpa- ice 
rent green colour, as in the chasms and crevices, while g! 
that which is near the heaps of gravel, is ‘of a bluish 
black colour.. The only exception to the generality of 
this remark occurs in the glacier of Rosboden, the le 
of which consists of ice, mands firm, and compact, and 
of a blackish blue colour. : 
The vaults of ice are always formed at the exit of the y, 
In winter; ice, 
all these 15 are closed up by ice, but the heat 
of spring speedily dissolves it, and vaults sometimes. 
100 feet long, and 50 or 60 wide, are formed. The 
figure and magnitude of these suffer constant changes. 
That of the Aveyron, once so much admired, is no 
longer in existence. OA a 
Inthe extensive alpine chain from Montblanc 'to the on 
borders of the Tyrol, there are no fewer than 400 gla nu 
ciers, the greater part of which are six or seven leagues’ 4 
long, by one half’ or three quarters of a league wide; ~~ °~ 
and from 100 to 600 feet thick. A very few of these ~ 
are so small as a league in length. M. Ebel has cale 
culated, as nearly as can be done, their general extent, — 
and has found that those between Switzerland and Mont- 
blane, ‘and on the frontiers of the Tyrol, would form a 
single glacier of 130 square leagues. sorte ae 
For farther information-on this subject, we must re- 
fer the reader to the article Aurs, where he will find 
an account of the glacier of Furea, the glacier of the 
Aar, and the glaciers of Grindelwald and Lauterbrun- 
nen. See also Grouner’s Histoire Naturelle des Gla- 
ciers de Suissé, translated by Keralio; Saussure Voyages — 
