ART. III.—Travels through the Alps of Savoy, and other Parts of the Pennine Chain; with Observations on the Phenomena of Glaciers. By James D. Forbes, F.R.S., &c. 1 vol. imperial Svo.; with Plates, and Map. Edinburgh, 1843. THE 'HE object of Professor Forbes, in this elaborate and beautifully-illustrated work, is to give a detailed account of the great glacier districts of the Pennine Alps, from the western slopes of Mont Blanc on the one hand, to the eastern sides of Monte Rosa on the other, including the giant peak of the Mutterhorn, and innumerable other intermediate regions. His excursions had in view principally the accurate observance of glaciers, and the careful study of whatever might tend to the establishment of the true theory of these great natural phenomena; but the volume is as far as possible from being a frigid specimen of scientific writing. On the contrary its peculiar merit consists in the combination of minute and ever watchful attention to the details of technical observation and experiment, with an expansive and indeed poetical perception and expression of those most wonderful aspects of nature by which the Alpine traveller is surrounded. Switzerland is without doubt the most finely-featured and strikingly diversified country in the world for the admirer of natural scenery. We do not believe that even the loftier heights of the Himalaya or the Andes afford effects more magnificent, if indeed they equal the grandeur of the great central groups of Europe. The latter, if less vast, are for that very reason more varied; and the traveller thus never feels the tedium of monotony which is doubtless produced by a long continuance of the same kind of grandeur, however superlative. 'Add to this,' says Professor Forbes, that the actual height of the zone of perpetual snow is as great as that of any mountains in the world, with one or two exceptions; for the highest land on the surface of the globe is near the equator, where the corresponding high temperature raises the limit at which perpetual snow commences to nearly the extreme height of European mountains. The eye, which must always have some actual or conventional standard of reference, if it cannot judge by the level of the sea, takes the level of the plain as a startingpoint; or, if there be no plain, the level of perpetual snow is a natural index of elevation, which, connected as it is with height, solitude, and vastness, impresses the mind with the highest sense of grandeur in natural scenery. It has often been observed that Chimborazo is less elevated above the table-land from which it rises than Mont Blanc is above the valley of Chamouni; and taking the level of perpetual snow in the Alps at 8500 feet, Mont Blanc is snow-clad throughout its higher 7000 feet. Now, a peak in the Himalaya range, in order to show as much, much, would need to rise to above 22,000 feet-a height which few of them exceed.'-p. 12. 6 It is these and other notices of a corresponding kind which, pervading the present work, bestow upon it a substantiality so seldom found in our ordinary Journals and Tours de force,' so many of which illustrate rather activity of body than accuracy of mind. We may add that, in addition to Mr. Forbes's natural and acquired qualifications for the fulfilment of his task, his opportunities have been ample. He had the advantage, he informs us, of receiving his first impressions of Switzerland in early youth; and these he has carefully refreshed and strengthened by successive visits to almost every district of the Alps between Provence and Austria. He has crossed the principal chain twenty-seven times, generally on foot, by twenty-three different passes, and has intersected the lateral ranges in various directions. His accomplishments as a natural philosopher are widely known. Had he been an angler and an entomologist, the circle of his capacities would have been complete. That portion of the Alps of Switzerland and Savoy called the Pennine chain is strongly characterised by the great number and large extent of its glaciers. From the increasing coldness of the atmosphere as we ascend, the upper portions of all extremely lofty mountains must be covered with snow. Whilst the plains are covered with the verdure of summer, eternal winter reigns upon the summits; and thus the stupendous ranges of the Himalaya or the Andes present, in one condensed picture, all the climates of the earth, from the tropics to the poles. A snow-covered mountain, however, is not itself, neither does it necessarily produce, a glacier; and why these icy ranges are found in certain countries and not in others, of which the natural climate and prevailing attributes seem quite the same, is a point which we shall not attempt to solve; but let Professor Forbes now inform us of what is meant by a glacier, in the ordinary acceptation of the term : ** "The common form of a glacier is a river of ice filling a valley, and pouring down its mass into other valleys yet lower. It is not a frozen *Mr. Moore sings of Eastern Alps, "Whose head in wintry grandeur towers, And whitens with eternal sleet, While summer, in a vale of flowers, Is sleeping rosy at their feet.' There is, however, no sleet upon the extremest heights of any Alpine mountains, where the snow, from never-absent frost, falls dry and powdery. There is a great difference between perpetual snow and perpetual congelation. The latter condition is inconsistent with sleet, which results from a reduction of temperature; but it would be scarcely fair to expect always both rhyme and reason, ocean, ocean, but a frozen torrent. Its origin or fountain is in the ramifications of the higher valleys and gorges which descend amongst the mountains perpetually snow-clad; but what gives to a glacier its most peculiar and characteristic feature is, that it does not belong exclusively or necessarily to the snowy regions already mentioned. The snow disappears from its surface in summer as regularly as from that of the rocks which sustain its mass. It is the prolongation or outlet of the winter world above; its gelid mass is protruded into the midst of warm and pine-clad slopes and green sward, and sometimes reaches even to the borders of cultivation. The very huts of the peasantry are sometimes invaded by this moving ice; and many persons now living have seen the full ears of corn touching the glacier, or gathered ripe cherries from the tree with one foot standing on the ice. 'Thus much, then, is plain, that the existence of the glacier in comparatively warm and sheltered situations, exposed to every influence which can ensure and accelerate its liquefaction, can only be accounted for by supposing that the ice is pressed onwards by some secret spring, that its daily waste is renewed by its descent, and that the termination of the glacier, which presents a seeming barrier or crystal wall immoveable, and having usually the same appearance and position, is, in fact, perpetually changing a stationary form, of which the substance wastes a thing permanent in the act of dissolution.'-p. 19. From the lower end of all large glaciers there consequently runs a stream of very chill and rather turbid water, derived from the melting of the ice and snow, the rain of summer, and the natural springs which no doubt occur in the bed or basin of the icy vale. The waste of the glacier itself during the warmest months may be presumed to yield the main supply of moisture, and hence many of the continental rivers which flow from Alpine sources are observed to have their greatest floods in July. So also does the voice of the mountain torrent become louder and louder as the day advances, while it diminishes towards evening, and is least of all in early morning. Nothing is more striking than the contrast which day and night produce in the superficial drainage of the glacier. No sooner is the sun set than the rapid chill of evening, reducing the temperature of the air to the freezing-point or lower, the nocturnal radiation at the same time violently cooling the surface-the glacier life seems to lie torpid-the sparkling rills shrink and come to nothing-their gushing murmurs and the roar of their waterfalls gradually subside-and by the time that the ruddy tints have quitted the higher hill-tops, a death-like silence reigns amidst these untenanted wilds.'-p. 21. But how beautiful to the eye and mind-more striking, indeed, from their increased solemnity-are the subdued glories of that nocturnal scene! The moon, an unconsuming fire, may be rising slowly from among the wooded steeps of the Montanvert, casting her silvery light into the depth of shadowy vales, or spreading a more more ample lustre over the vast expanse of snow-covered mountains. The gigantic rocky spires, called Aiguilles, rise in grey and ghastly grandeur amid the eternal snows, attaining to various elevations from 10 to nearly 14,000 feet above the sea, while between those heights, And on the top of either pinnacle, More keenly than elsewhere, in night's blue vault The sky itself is indeed almost black from the excessive depth of its crystalline clearness. The lower extremity of a glacier, where its huge wedges seem to furrow up the 'clods of the valley,' is usually steep, broken, and nearly inaccessible; its intermediate portion, if not level, is at least more regularly inclined; its upper part becomes again rougher and more precipitous. Its entire surface is more or less broken up by what the French term crevasses, which are not crevices in our sense of the word, but rents or dislocations of various dimensions, some being so large and prolonged as during their continuance to debar all passage from one portion of the ice to another. Although the vertical sides of these crevasses are often translucent as glass, yet the general surface of a glacier presents no resemblance to that of water frozen in a state of tranquillity, such as we see it on lakes. The surface is not only irregular but rough, and the texture of the ice wants that unity of structure observable on frozen lakes. From a distance it no doubt presents a more unbroken aspect; but on a near inspection, or on actual contact, the irregularities are frequently found so great as to render a walk of any length extremely toilsome -even the staunchest pedestrian will by and bye prefer a scramble along the broken rocky ground on either side. The ridges are caused chiefly by the flowing of surface water, which collects into little rills and runs along the ice, thus scooping out the intermediate hollows, till it meets its match in some great crevasse, into whose icy jaws it drops and disappears. Smaller portions of the glacier, protected from solar heat by some huge stone, have also a singular apparent tendency to rise above the neighbouring surface; that is, the shade of the stone screens them from the melting process to which the general superficies is subjected, and so, raised as it were on stalks or pedestals, they stand for a time in ghostly pre-eminence a city of death distinct with many a tower.' On the Mer de Glace, nearly opposite the place called Couvercle, there is a remarkable block of granite which particularly attracted Mr. Forbes's attention on his first visit to that portion of the glacier in 1842 "It is a magnificent slab of the dimensions of 23 feet by 17, and about 3 feet in thickness. It was then easily accessible, and by climbing upon it, and erecting my theodolite, I made observations on the movement of the ice. But as the season advanced it changed its appearance remarkably. In conformity with the known fact of the waste of the ice at its surface, the glacier sunk all round the stone, while the ice immediately beneath it was protected from the sun and rain. The stone thus appeared to rise above the level of the glacier, supported on an elegant pedestal of beautifully veined ice. Each time I visited it, it was more difficult of ascent, and at last, on the 6th of August, the pillar of ice was thirteen feet high, and the broad stone so delicately poised on its summit (which measured but a few feet in any direction), that it was almost impossible to guess on what side it would ultimately fall, although by the progress of the thaw its fall in the course of the summer was certain. On a still later day I made the sketch in the frontispiece, when probably it was the most beautiful object of the kind to be seen anywhere in Switzerland. The ice of the pedestal presented the beautiful lamellar structure parallel to the length of the glacier. During my absence in the end of August, it slipped from its support, and in the month of September it was beginning to rise upon a new one, whilst the unmelted base of the first was still very visible upon the glacier.'—p. 92. The lowest portion of the Mer de Glace, where it is named the Glacier des Bois, being steep and rugged, the great ice valley is usually visited by ascending the Montanvert, which bounds a portion of its western shore, and then descending to its lateral surface. But the scene from the terminal slope below is extremely fine: "To the right and left the prospect is inclosed by the warm green firwoods, which touch either snow-line of the glacier, and behind and aloft the view is terminated by the stupendous granitic obelisk of Dru, which has scarcely its equal in the Alps for apparent insulation and steepness; a monolith by whose side those of Egypt might stand literally lost through insignificance.' The summit of the Montanvert is about 6300 feet above the level of the sea, and its ascent forms a pleasant and picturesque morning walk from the village of Chamouni, of which the elevation is already upwards of 3400 feet. In the days of Saussure (1778) there was no other shelter on the mountain than a huge block of granite, with an overhanging face, the hollow portion screened by a rude wall, in the upper part of which was a small doorway. Such was the ancient castle of the shepherd of Montanvert. A few years later, we find from one of Link's coloured views, that a small cabin with a wooden roof had been erected, probably by an Englishman, as it bore the name of Blair's Hospital.' At the period of our own vist (in 1815) there was a substantial hut, of one apartment, which had been built at the expense of M. Desportes, French Resident at Geneva. How long |