In ascending the valley, for the purpose of crossing the Col de Balme, we saw also the glaciers of Argentiere and Trient, which do not merit any particular description. The glacier of Argentiere lies at the foot of the lofty aiguille of the same name. It is covered at its extremity with blocks of granite, and almost blackened by a profusion of granite sand.
There is another species of glacier of a very interesting nature, but essentially different from those which we have described. One of them is in France near Beaume, and the other in the Carpathian mountains of Hungary. The first of these glaciers is near the village of Beaume, in a deep cave. The mouth of the cave is forty-five feet wide, and after reaching by a long descent a hall 100 feet high, a lad der of about 40 feet long conducts to the glacier. About the beginning of the last century it was completely filled with ice, which was renewed every summer. The water, which descended on all sides from the surface, formed huge pyramids of solid ice, partly hanging from the rock, and partly shooting up from below. In winter, this cavern, which is 700 or 800 feet below ground, was filled with smoking water. The ground above it was formerly cover ed with huge trees, which kept off the sun's rays ; but in 1724, a country-house having been erected on the place, the trees were cut, and the ice carried away for the use of the proprietor. The entrance of the cavern was covered up with a wall, and the ice has not formed so rapidly since that time. The glacier and cavern of Tselitz is in a very lofty rock in the Carpathian mountains. Its mouth is large, its width is 26 fathoms, and it penetrates 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. M. l3e1 informs us, that six hundred carts would not he able to carry of 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.
It was long the opinion of the vulgar, and even of some intelligent writers, that the glaciers increased from below ; and I\1. Altmann was the first who maintained their true origin, although he erroneously supposed that the pyramids of ice rose from the glacier itself In order to explain the origin of glaciers, let us suppose that all the lofty moun tains and peaks which surround the Glacier de Bois have been covered with snow doting winter. At the approach of spring, the snow at low altitudes, and at the place where the glacier itself exists, is completely melted by the influ ence of the sun and the rains. At a greater altitude, vary ing with the latitude of the place, and with local circum stances, the snow is only pat tly melted, and having, there fore, imbibed a great quantity of water, it is frozen into a mass of imperfect 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 equi librium of the mass is destroyed, either by its own mag nitude, or by other causes, and the whole is precipitated in the form of an avalanche into the valley below. 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 declivities is easily loosened by any sudden thaw, and falling down, it adds either to the ac cumulated ice below, or passes directly to the bed of the glacier. The ice thus collected from the surrounding heights will experience particular changes in its new situa tion. It is now subject 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 propagat ed throughout the whole glacier.