by dangers which cannot be justly described, by the 4th of June they had accomplished an opening 600 feet long; but having begun their work on both sides of the dike at the same time, the place where they ought to have met was 20 feet lower on one side of the lake than on the other: it was fortunate that latterly the increase of the perpendicular height of the water was less, owing to the extension of its surface. They proceeded to level the highest side of the tunnel, and completed it just before the water reached them. On the evening of the 13th the water began to flow. At first, the opening was not large enough to carry off the supplies of water which the lake received, and it rose 2 feet above the tunnel; but this soon enlarged from the action of the water, as it melted the floor of the gallery, and the torrent rushed through. In thirty-two hours the lake sunk 10 feet, and during the following twentyfour hours 20 feet more; in a few days it would have been emptied; for the floor melting, and being driven off as the water escaped, kept itself below the level of the water within; but the cataract which issued from the gallery melted, and broke up also a large portion of the base of the dike which had served as its buttress: its resistance decreased faster than the pressure of the lake lessened, and at four o'clock in the afternoon of the 16th of June the dike burst, and in half an hour the water escaped through the breach, and left the lake empty.

"The greatest accumulation of water had been 800,000,000 of cubic feet; the tunnel, before the disruption, had carried off nearly 330,000,000 Escher says, 270,000,000; but he neglected to add 60,000,000 which flowed into the lake in three days. In half an hour, 530,000,000 cubic feet of water passed through the breach, or 300,000 feet per second; which is five times greater in quantity than the waters of the Rhine at Basle, where it is 1300 English feet wide.

In one hour and a half the water reached Martigny, a distance of eight leagues. Through the first 70,000 feet it passed with the velocity of 33 feet per second four or five times faster than the most rapid river known; yet it was charged with ice, rocks, earth, trees, houses, cattle, and men; thirty-four persons were lost, 400 cottages swept away, and the damage done in the two hours of its desolating power exceeded a million of Swiss livres. All the people of the valley had been cautioned against the danger of a sudden irruption; yet it was fatal to so many. All the bridges in its course were swept away, and among them the bridge of Mauvoisin, which was elevated 90 feet above the ordinary height of the Drance. If the dike had remained untouched, and it could have endured the pressure until the lake had reached the level of its top, a volume of 1,700,000,000 cubic feet of water would have been accumulated there, and a devastation much more fatal and extensive must have been the consequence. From this greater

:

danger the people of the valley of the Drance were preserved by the heroism and devotion of the brave men who effected the formation of the gallery in the dike, under the direc tion of M. Venetz. I know no instance on record of courage equal to this their risk of life was not for fame or for riches—they had not the usual excitements to personal risk, in a world's applause or gazetted promotion, their devoted courage was to save the lives and property of their fellow-men, not to destroy them. They steadily and heroically persevered in their labours, amidst dangers such as a field of battle never presented, and from which some of the bravest brutes that ever lived would have shrunk in dismay. These truly brave Vallaisans deserve all honour!"

But the skill of M. Venetz was not limited in its application to emptying the lake his abilities have been

properly directed to the prevention of such another catastrophe, for the liability to its recurrence was obvious. Not one twentieth part of the ice which formed the barrier, had been removed when the dike burst, and fresh masses were still falling from Mont Pleureur and Mont Mauvoisin, the mountains of which the bases formed the buttresses to the dike; in fact the dike was again accumulating so rapidly, that at the end of 1819 the barrier was almost as complete, as before its bursting from the pressure of the lake.

It became therefore an important object to prevent a repetition of the former catastrophe, by the adoption of such means as would prevent, or at least diminish, the increase of the barrier. Blasting by gunpowder was found impracticable, from the difficulty of firing the powder at considerable depths in the ice, and from the comparatively small masses removed by this means. After much consideration and many trials, a mode has been adopted and put in execution by M. Venetz, which promises the great

est success.

"M. Venetz had remarked that the glacier could not support itself where the river was of a certain width, but fell into it and was dissolved; whereas, where the river was comparatively narrow, the ice and snow formed a vault over it, and consequently tended to the preservation of any portion falling from the glacier above. Perceiving also the effect of the river in dissolving the part it came in contact with, he formed and executed the design of bringing the streams of the neighbouring mountains by a canal to Mauvoisin, opposite the highest part of the glacier where it touched that mountain. From hence it was conducted by wooden troughs on to the glacier in a direction parallel to the valley. The water was divided into two streams; one falling nearly on the one edge of the Drance, and the other on the

other; and having been warmed by the sun in its course, soon cut very deep channels in the ice. When they reached the river the troughs were removed a few feet, and thus the stream produced the effect of a saw, which, dividing the ice, forced the portion between them to fall into the Drance.

"When the weather is fine, these streams, which are not more than four or five inches in diameter, "act with extraordinary power, piercing a hole 200 feet deep and six feet in diameter in 24 hours. They are calculated to remove 100,000 cubical feet of ice from the barrier daily, and it is supposed that if the weather is fine the whole will be removed in three years.

"At the end of the season of 1822 the Drance remained covered only for a length of 480 feet; whereas, at the commencement of the operation, it was covered over a length of 1350 feet. M. Venet estimates the quantity of ice removed in 1822 as between eleven and twelve millions of cubical feet."- Bib. Univ. xxii. 58.

The châlets above Getroz can be reached in good time in one day from Martigny; and those who wish to cross the glaciers of Charmontane can sleep at the châlets, and, starting early the next morning, push on to the extremity of the valley, cross two glaciers, and attain the summit of the pass of the Col de la Fenêtre in time to reach Aosta on the following day.

These enormous glaciers have a greater extent, commanded at one glance, than perhaps any other in the Alps. With crampons on the feet, the traverse, it is stated, by one who has recently passed, is neither dangerous nor difficult, but very fatiguing from their great extent. As they are seen to stream into their channel from the lofty peaks of the Combin and the Velan, they offer to the enterprising traveller one of the grandest views in the Alps. The elevation of the Col

Nor is this the only pass by the Val Pellina across the great chain. Another is practicable, and, though difficult, is not dangerous, by the Col d'Ollen, which lies between the châlets of Prerayen, in the Val Pellina, and St. Barthelemy, above Evolena in the Val d'Herens, or Eringerthal, which opens into the Vallais, near Sion. A servant of the innkeeper of St. Remy, on the Italian side of the Great St. Bernard, has been with more than one traveller by this pass, and by another at the head of the Val Pellina, which leads from Levornea to Val Tournanche and the Val d'Aosta.

From the Col de la Fenêtre the descent is long and fatiguing to Balme, the first hamlet, and to Ollomont, where there are traces of an aqueduct built by the Romans for the supply of water to Augusta Prætoria. Thence the road descends through the village of Valpellina, and still lower that of Rogniant, near to where the Buttier is crossed, and the path leads into the city of

which, divided on the crest, descend towards the Val de Ferret, as the glaciers of Salena, Portalet, and Neuve; and, on the other side, towards the west, form the glaciers de Trient, du Tour, and d'Argentière.

There is nothing, however, remark. able in the scenery of the Val de Ferret. The route leads up a suc cession of rather flat divisions of the valley, from Issert to the Châlets de Folie, distant 2 hours. On the right, the short transversal valleys, or rather crues, in the side of the mountains, are the channels for these glaciers.

Above the Châlets de Folie, the usual path to the Col de Ferret leads up through the Châlets of Ferret, by the detritus of a mountain which fell in the year 1776, burying the pasturages of Banderai. Near to these châlets the two paths separate that on the left leading over the Col de la Fenêtre to the Great St. Bernard, that on the right to the Col de Ferret.

Instead, however, of ascending by Ferret and the Châlets of Banderai, the guides now take a shorter path directly up the pasturages on the right, above the Granges of Folie ; but, without a guide, this may lead into scenes of danger, towards the deep crues and precipices which form the eastern side of the great chain of Mont Blanc- -scenes of impressive grandeur, from their vastness and utter sterility.

The ascent by the shorter path is very steep and fatiguing to the Col de Ferret; but the view when near the summit well repays for the trouble of attaining it, the time required from the Châlet de Folie being about two hours.

From the ascent, the whole Val de Ferret is seen, bounded on either side by lofty mountains, and the distance is limited only by the Bernese Alps.

The woods and pasturages of part of the Val de Ferret belong to the Convent of the Great St. Bernard,

and at this distance from the hospice

4 or 5 leagues the brethren obtain all their wood and some hay.

From the crest of the Col de Ferret, the view along the south-eastern side of Mont Blanc, towards Piedmont, is one of the scenes celebrated by Saussure. The eye is carried through the Val d'Entrèves and the Allée Blanche to the Col de la Seigne, an extent of 40 miles. Numerous glaciers are seen on the right, streaming down into the valley from the great glaciers of Mont Blanc; but the "Monarch" himself is not seen, the enormous masses of the Grand Jorasse and the Géant conceal him in this view.

The descent is over a soft slaty soil, in which the tracks of sheep and cattle have cut deep trenches, in which if a man stand he is half concealed. Ten minutes below the Col a cross is placed on the edge of a precipice which the path passes; it serves to guide the course of the ascending traveller, though from below it seems to be placed on a pyramidal mass of rock which it would be impossible to attain. Far in the deep valley, the stream flowing into Italy appears like a thread of silver.

An hour and a half of fatiguing descent brings the traveller to the Châlets of Pré de Bar, famed for being the dirtiest in Piedmont.

Near Pré de Bar the vast glacier of Triolet sweeps down from the crest which divides this glacier from the masses, which, on the other side, form the glacier of Talefre. Below the glacier of Triolet the road de scends by a most fatiguing path, amidst rocks and stones and bushes, presenting a scene of Alpine desolation. The valley is very narrow, and each rift on the mountain side towards Mont Blanc has its glacier hanging down from the summit. Not less than seven distinct glaciers are passed in the course of this valley, before reaching the village of Entrèves, near to Cormayeur. These chiefly depend from the masses which form the

111. Aosto to Ponte.

Grand Jorasse, and the remarkable peak of the Géant. A few miserable villages in the Val d'Entrèves are passed. The highest is Sagion; those below are Pré-sec and Plan-pansier. More than half the length of the valley is passed, on the descent, before Mont Blanc is seen: when its prodigious mass opens to the view, the effect is overwhelming. The ruggedness of the descent is increased by passing over the débris of a mountain fall beneath the Géant. This passed, the river, which descends through the Val d'Entrèves is crossed, the village of Entrèves is left on the right, and, winding along a path by the side of the mountain, Cormayeur (Route 107.), is reached in 15 or 16 hours from Martigny.

ROUTE 111.

AOSTA TO FONTE IN VAL D'ORCA, BY COGNE, FENÊTRE DE COGNE, THE COL DE REALE, AND THE VAL

SOANNA.

(Three Days.)

From Aosta (Route 107. p. 277.) a road leads directly down to the river, Doire, which is crossed on a wooden bridge,and a path ascends on the right bank through the rich plain of the valley, and through the villages of Gressau and Joveneau to Aimaville, about a league and a half, where one of the most fantastical offences to good taste in building, spoils one of the finest sites in the valley. A knoll jutting out into it is surmounted with a squab, square mass of masonry, a modern antique, worse than any cockney attempt to decorate a garden with a castle. At Aimaville there formerly existed an ancient pagan temple, which was succeeded by an establishment of knights templars; and within the present queer structure is an ancient armoury of the barons

of Aimaville. It is now inhabited by the Contessa di Rocca.

From the château the ascent is steep to the hamlet of St. Martin. The view from the crest above it is perhaps the finest in the Val d'Aosta, in the richness of its plain, studded with villas and châteaus. The city is seen as in a glorious frame, and beyond it, towards the great chain, the peaks of the Monte Rosa close this unmatched scene of the beautiful and magnificent in nature.

On turning the brow of the mountain which forms the southern side of the entrance to the Val de Cogne, a path at an elevation of at least 1000 feet above the torrent of the Cogne, leads into the valley. Soon after losing sight of Aosta, deep in the valley beneath the path, the tops of the cottages of Pont d'Ael are seen clustered with a few trees, and near it a white line which crosses the ravine. This is well worth an examination, and a path leads down to this remarkable village, where the line crossing the gulf will be found to be an ancient aqueduct, which now serves as a road. This is one of the most remarkable of the Roman structures remaining in the Val d'Aosta, from the times of the empire. It is raised nearly 400 feet above the torrent, which it crosses by a single arch: immediately above the arch, and under the present road, is the ancient gallery, which is lit through slits in the wall.

The

This gallery is 180 feet long, 14 feet high, and 3 feet wide. vault is composed of the slabs which formed the bed of the ancient watercourse. The gallery is entered by arched ports at either end; there are two, one on the upper side, at the village of Pont d'Ael, and at the other end the port opens down the valley. This singular work is in perfectly sound condition, though built, as a still legible and even sharp inscription indicates, by Caius Aimus and his son, of Padua, in the thirteenth year of Augustus. This inscription is inaccessible; it is placed on a tablet just over the arch

on the lower side towards the valley of Aosta. Though it cannot be reached, to which fact it probably owes its preservation, yet it can be readily read from the brink of the precipice on the side of Pont d'Ael, and the fol lowing is the inscription:

IMP. CESARE AUGUSTO XIII. COS. DESIGN. C. AVILLIUS C. F. C. AIMUS PATAVINUS PRIVATUM.

Their name is still preserved in the village and château of Aimaville.

The distance from Aosta to Pont d'Ael by the route described is nearly 3 hours' walk.

Travellers in the Val d'Aosta should not fail to visit this interesting work of antiquity, which is placed in a situation where it is impossible to imagine that any benefit could ever have arisen commensurate with the expense of the structure. The surrounding scenery is very grand.

In ascending the valley of Cogne, it is not necessary to retrace one's steps to regain the path high upon the mountain side. A shorter cut from Pont d'Ael leads to it; the valley for a long way above Pont d'Ael is a fearful ravine, utterly impracticable in its depth, which, except at two or three points, is equally impervious to the eye. In some places the narrow path on the edge of the precipices, wretchedly guarded by poles and trees, which a child might throw over, is so obviously dangerous, that none but a practised mountain traveller could pass some places without a shudder. Opposite to one spot, where the path turns suddenly into a deep rift or crue in the mountain side, is a slide, down which trees cut in the forest above are discharged, for the chance of the torrent bringing them down to the Val d'Aosta. Not one in ten escape being broken into splinters; these, however, serve for the usines and founderies for working the iron raised in the Val de Cogne, and which is celebrated in Piedmont.

The difficulties of constructing a