wards found to have slid three miles, consisting of rocks, earth, trees, &c., with an average breadth of a quarter of a mile. The excavations commenced generally in a trench a few yards in depth, and a few rods in width, and descended the mountain, widening and deepening until they became vast chasms. Forests of spruce and hemlock were apparently prostrated with as much ease as if they had been fields of grain. The valleys of the rivers Amunoosuck and Saco presented for many miles, an uninterrupted scene of desolation; all the bridges being carried away and the ground strewed with the wrecks of trees and rocks, and in many instances large quantities of soil. In some places the road was excavated to the depth of 15 or 20 feet; and in others it was covered with rocks, trees and soil to as great a height. In various places, as shown by the remaining marks, the water rose to the height of 25 feet above its ordinary level.

But these thing are of little consequence when compared with the human suffering which this catastrophe occasioned, for a family of nine persons were destroyed on the night of the 28th, and not one lived to relate the cir

cumstances.

In

This family, named Willey, occupied a house at the foot of the mountain, a most lonely place, six miles from any other human habitation. It was a resting place for travellers. On the morning of the 28th the house was found standing but not a human being was there. the course of a few days seven out of the nine bodies were found at a short distance below the house, buried under the ruins of the mountain, and most of them shockingly mangled. It appeared that one of the heaviest slides from the top of the mountain had rushed in the most impetuous manner towards the house, but when within six feet of it had divided, and passed on each side, leaving the house untouched, but sweeping away the stables and horses. At this time it is supposed that the family left the house, and met their destruction; had they remained, all would have been safe.-Silliman's Journal for January, 1829.

Flood in the Valley of Bagnes, in 1818. The Valley of Bagnes forms a part of the main valley of the Rhone, above the lake of Geneva, in Switzerland. Through this

valley passes the river Dranse, which falls into the Rhone above the lake. In 1818, in consequence of the fall of avalanches, the Dranse was completely dammed up, so that a barrier of ice remained across its channel, until the melting of the snow in the spring, formed a lake in its bed, a mile and a half in length, about seven hundred feet wide, and in some places two hundred feet deep. To prevent the consequences apprehended from the sudden bursting of this barrier, the people cut a tunnel through it, several hundred feet in length, before the water had risen to any considerable height. When the water had accumulated so as to reach this tunnel, or gallery, it ran through, and melting the ice it drained off about one half of the lake. But at length, on the approach of the hot season, the central portion of the remaining mass of ice gave way with a tremendous crash, and the residue of the lake was emptied in half an hour. In the course of its descent, the water encountered several narrow gorges, and at each of these it rose to a great height, and then bursting its barriers, rushed forward with increased violence, sweeping along rocks, hous s, trees, bridges, and cultivated lands. For the greater part of its course, the flood resembled a moving mass of rocks and mud, rather than of water. Some fragments of primary rock of enormous magnitude, and which from their dimensions, might be compared, without exaggeration, to houses, were torn out of a more ancient alluvion, and borne down for a quarter of a mile. The velocity of the water in the first part of its course, was thirtythree feet per second, which diminished to six feet, before it reached the lake of Geneva, where it arrived in six hours, the distance being 45 miles.

This flood left behind it on the plains of Martigny, thousands of trees torn up by the roots, together with the fragments of many buildings. Some of the houses in the town of Martigny were filled with mud up to the second story. After expanding in the plain, where the town stands, it passed into the Rhone, and did no further damage. Many lives were destroyed by this flood, and the bodies of several persons were found on the surface of the Geneva lake, thirty miles from the place where they were swept away.

Inundations precisely similar, and from the same cause, are recorded to have happened in former periods. In 1595, the town of Martigny was destroyed by such a flood,

and from sixty to eighty persons perished; and in a similar catastrophe which took place, fifty years before, one hundred and forty persons lost their lives.

For several months after the debacle just described, the river Dranse, having no settled channel, shifted its position continually from one side to the other of the valley, carrying away newly erected bridges, undermining houses, and continuing to be charged with as large a quantity of earthy matter as the fluid could hold in suspension.' See Ed. Phil. Jour. vol. 1. p. 178: and Lyell's Geology, vol. 1. p. 194.

Now although we have no disposition to deny that great changes have been wrought on the face of the earth by the power of running streams, the bursting of lakes, &c. yet all these effects combined, utterly fail to account for the appearances enumerated under the article "Deluge." The phenomena presented by the great valleys of the Alps, the Pyrenees, and the Jura, cannot be attributed to any cause, but a sudden and mighty torrent of water, such as no one has thought fit to ascribe to the bursting of a lake, and of which history contains no account, except that of the Noachian deluge.

CHANGES EFFECTED BY SPRINGS.

The Theory of springs will be reserved for another place. At present, our object will be to show the effects which springs have had in changing the surface of the globe.

It is obvious that springs of pure water, unless uncommonly powerful, will produce but little effect on the surface along which they run, and with a few exceptions, their excavating effects are scarcely to be taken into account. But springs which contain carbonic acid gas, often hold.considerable quantities of calcareous matter in solution, and which is deposited along their courses, producing what geologists term calcareous tufa, or travertine.

Ma

These deposites are generally porous, and mixed with leaves, bits of wood, mud, &c. but when more pure, they are so solid as to be employed for building stones. ny of these springs are thermal, or warm, and abound chiefly in volcanic countries.

In those parts of France and Italy which skirt the Ap

ennines, innumerable mineral springs, chiefly containing carbonate of lime, issue from the ground. As the water evaporates, the lime is left on the surface, and thus the ground in some parts of Tuscany is covered to a considerable extent with the kind of deposite called Travertine, already noticed. In some places these deposites are solid and smooth on the surface, much resembling currents of lava.

Baths of San Vignone. This spring is also in Tuscany, and affords a striking example of the rapid precipitation of carbonate of lime from thermal waters. The spring issues from near the summit of a hill about one hundred feet high. The water is hot, but Mr. Lyell, from whom this account is taken, does not give its temperature.

So rapid is the deposition from this water, that a pipe leading from the spring to the baths, and inclined at an angle of thirty degrees, is found to contain a coat of solid limestone half a foot thick every year. A mass of solid rock below the hill, formed by this water, is two hundred feet thick. This is employed as a building stone, and in quarrying it, Roman remains of art, such as tiles, have been found five or six feet below the surface, being covered by the deposite.

Baths of San Filippo. These baths are situated only a few miles from those already described. The waters which supply them are impregnated with carbonate of lime, and sulphate of lime, (gypsum.) They flow from the spring immediately into a pond where in twenty years a solid rock is deposited thirty feet thick. A curious manufactory which produces medallions in basso-relievo is carried on at this place.

The water is first allowed to stand in a cistern where the sulphate of lime is deposited. It is then conveyed to a chamber through a tube, from the end of which it falls ten or twelve feet, the current being broken by numerous small sticks crossing each other, and by which means the spray is dispersed around the room. Here are placed the moulds of the medallions to be formed, which are first rubbed over with a little soap. The water striking on these moulds leaves particles of carbonate of lime, which gradually increasing, leaves exact and beautifully white casts of their figures.

The solid matter left by this spring, is a mass of limestone and gypsum rock, a mile and a quarter long, the third of a mile in breadth, and in some places at least two hundred and fifty feet in thickness. The length of this deposite terminates abruptly, being crossed by a small stream, which carries away the undeposited matter with the waters of the spring, otherwise it would have been much more extensive.

The quantity of matter deposited from these springs, show the newness of the earth, or at least of the present order of things on its surface; for had they existed at the period when Mr. Lyell supposes the cataract of Niagara was at Queenstown, and discharged their waters, and formed depositions as they do at the present day, and which it is certain they did at the time of the Romans, these strata ought to have been at least ten thousand feet thick. It is true, however, that these thermal springs being caused by volcanic heat, might have been formed within the last two thousand years.

It is apparent from what has been stated concerning calcareous springs, that in the lapse of ages considerable changes must have been made in the earth's surface from this source. But it must not be forgotten that this cause is local in its nature, being confined chiefly to volcanic districts; and that even such districts seldom contain springs which work such changes as are above described.

Silicious Springs. Although we possess no chemical process by which water can be made to dissolve pure silex, or flint, yet in the great laboratory of nature, this effect is produced. There is, however, a process in chemistry, in which by a previous combination, silex becomes soluble in water, and which, perhaps, affords an analogy to the process employed by nature. If silex be finely pulverized, and then melted with a quantity of common alkali, the whole becomes soluble in hot water. Now springs containing any considerable quantity of silex, are always of high temperatures; and it is to the great degree of heat which exists at their sources, together with small portions of alkali which volcanic rocks contain, and which the water dissolves, that we are to attribute the property these waters possess, of holding silex in solution. Springs containing any considerable quantity of silex, are, however, exceedingly rare, and are mentioned here, rather on this

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