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advanced, the heat became greater than in any of the valleys below, and very oppressive, from both the direct rays of the sun and those reflected from the surface of the ice, and from the sides of the mountains covered with ice and snow. At ten o'clock in the forenoon, the thermometer covered by its frame stood at 29° R. (73 Fahr.), at the height of 5 feet above the surface of the ice, and about 3000 above the level of the sea. A little farther up it sunk to the freezing point, at the depth of 5 feet down, in one of the clefts of the ice: in so short a time can you experience the temperature of every season.

But in spite of the African heat which prevailed in the glacier of Lodal, the labourers in the neighbouring fields of Melversdal required their winter clothing, which they generally wear in the warmest summer day, as the melting ice absorbs the heat, and often sends down upon them blasts of cold wind. Soon after the sun had begun to shine on the glacier and its neighbouring mountains, heat, Nature's great instrument of dissolution, began to shew its mighty power. The water from the melting ice flowed in more copious streams, and cut for itself deeper runs. Masses of ice sunk down into the clefts with a noise like the loudest thunder, which rolled along the winding valleys in innumerable echoes. The surface of the ice burst with a violent crack, when the heat expanded the air inclosed in cavities of the glacier. Huge masses of ice and snow, loosened on the steep sides of the mountains, were crushed to pieces on the rocks below, tumbling down with prodigious and long reflected noise. Fourteen or fifteen such proud avalanches fell while the sun was in his power. The ice reduced to powder by the force of the fall, mounted like dust raised by a whirlwind, while the heavier parts rushed down on the glacier like a mighty waterfall. Sometimes, also, vast fragments of rock fell upon the glacier's sides. Many small streams, too, like stripes of silver playing in the colours of the rainbow, gushed from the sides of the neighbouring mountains.

A little above the moraine of the glacier, where the road bends round towards Nordfiord, Lodal's Mantle begins to stretch out its white giant head. It takes this name from the valley over which it stands, and from its perennial covering of ice and

JANUARY-MARCH 1827.

snow. My active guide was as little acquainted with the road to the top of it as I was. Our ascent from the glacier began at the foot of the mountain on the north-east, at the height of 4500 feet above the sea. About 750 feet higher up, all water had disappeared, and the depth of the snow increased, although the heat in the sun was 29° R. The lowest point, therefore, above which snow never melts here, may be considered as about 5250 feet over the level of the sea. The steepness of the mountain made the ascent now pretty difficult: the rents in the ice, too, were deeper and broader ihan down on the glacier, and they were sometimes covered by snow. It became, therefore, dangerous to pass over them. You have often but a slippery footstep between you and death, and your first false step is your last in the world. From caution against such danger, we walked with a rope about our waist, and, trusting to this, we courageously crossed on a bridge of snow ten feet over. The difficulty of climbing was increased, by the inconceivable, and almost intolerable, heat of the sun, which, added to the thinness of the air, produced an uncommon weakness, and a pulse nearly doubled. We recovered our strength, however, in as short a time as we lost it, and it was not long before the naked summit was reached.

With some degree of alarm we climbed up its 150 feet high loose black head, that seemed to move under us: the top of this we reached at half past eleven A. M., on the 13th July. From a mean of six observations, which corresponded with those of Engineer Major Wetlessen, in Bergen, Dean Hertzbergen, in Hardanger, and Professor Esmark, in Christiania, and from calculations made according to the formula of La Place, the southern top of Lodal's Mantle is 6113 feet above the level of

It divides itself into three elevations, the summits of which and the steepest side are naked. The rest of the mountain to the bottom is covered with an everlasting and unbroken mantle of ice and snow. By other observations, we found, that the eastern and highest top was 6408 feet above the sea. Several circum-meridian observations of the sun gave the latitude 61° 57', though, from an accidental injury which happened to the sextant, this determination is less to be depended on.

The surface of a small stone we found on the top of the moun

the sea.

tain was, in different places, covered with two sorts of lichen, L. geographicus and another. A bear, whose gloomy disposition must have conducted it to these solitudes, had left its traces on the snow which had fallen within two days, and the laugh-re, sembling voice of a single ptarmigan was heard. With these exceptions, organic life and vegetation had disappeared, and eternal winter had taken up its abode all around. From the summit was seen an ocean of snow, of several thousand

geographic square miles extent, the waves of which seemed as if they had been instantaneously fixed, and over which single mountaintops here and there raised their white heads, which in the valleys were hid in the clouds.

Skatolstop * in Lyster, Tunderdalskirk towards Lomb, and Vangsen in Justedal, were the most remarkable. All was the stillness and desolation of death, which irresistibly filled the soul with melancholy, mingled with a powerful impression of the greatness of Nature.

The author here mentions, that, on two places in the glacier, they saw a little red snow: after which, he takes a survey of the adjoining region in all directions, in which he traces by name twenty-five distinct valleys, which, to a great extent, had been filled with layer upon layer of ice from this immense mountain. He then proceeds:-Our descent from Lodal's Mantle, after they had got past the naked rocks, was quick and easy, and, after having sojourned for nineteen hours in the regions of ice and snow, we returned to Stordal with weakened eyes, and with swollen faces and lips.

The river of Justedal has its source from the glacier of Lodal, in the upper and north-west end of Lodal. After running the whole length of Justedal, it falls into a small arm of Lysterfiord, near the farm of Rödnei. Many small rivers from the other glaciers of Justedal, and the adjoining mountains, unite with it, the most of which have fallen into it before it reaches Elvekrogen. It brings down with it great quantities of sand and mica, which are found chiefly on its banks near its source. Its waters have a greyish muddy appearance, by which rivers which come from

. This is one of those remarkable mountains called the Young Harlots. Its height is ascertained to be 6975 feet above the sea. It is south-east from Lysterfiord, and is seen very far off.

glaciers may be always easily distinguished. From the difference in the quantity of water furnished to it at different seasons of the year by the rain, and the melting of the snows on the mountains and glaciers, the width of its bed and its rapidity are continually varying. Sometimes in the course of two days it has changed its bed : in its course it exhibits many beautiful cascades. Often it sweeps before it beautiful holms, covered with trees and shrubs, overwhelming at the same time the adjoining corn-fields. In 1814, a flood in the river carried off large pieces of the meadows on its banks, rising so high, that the sand was found on the top-leaves of the trees. At Elvekrog it rose from 16 to 20 feet above its usual surface. As it descends from the icy regions in which it rises, its temperature becomes less fri-gid, till it reach Lyster, where the multitude of fruitful apple and cherry trees, the quantities of asparagus, &c. bespeak a warmer climate than could be there expected.

On a warm dry day, July 10, of which the mean temperature was 19o.7 R., the minimum depth of Justedal river opposite to the church was 6 feet in the morning; its maximum depth in the evening was about 8]. Such was the difference occasioned by the melting of the snow. The velocity of the current was at the rate of 8 feet in the second, when the river was at its minimum depth, and 9 when at its maximum. Taking the mean breadth of the river, and its slope from the sides to the middle, by simple calculation, we may form an approximation to the quantity of ice and snow melted by the heat of such a day. By this calculation it will be found, that a quantity of about 31,132 cubic fathoms of water is thus added to the river every hour. Assuming, then, that the snow has fourteen times less density than the water which comes from it, with other proper allowances, the result will be, that the quantity of snow melted into this river during half a summer's day, will amount to 5,230,176 cubic fathoms, which I have no doubt is less than the reality.

Observations on Serpentine and Diallage Rocks. By Dr A.

Boue'. In a Letter to Professor JAMESON. Communicated by the Author.

The geological relations of serpentine are still but imperfectly known ; for it is not many years since we were assured of the existence of transition serpentines in the form of short beds, or large masses in the veins, or bed-like veins, of the greenstone (diabase) of the Pyrenees (St Pé, and Valley of Baretons); in the greywacke of Girvan and Ballantrae in Scotland (Jameson), and of Bastberg in the Hartz; in the transition slates of the northern Fichtelgebirge, and of the Vosges ; in the transition limestone of Willendorf in Austria ; in the Carpatho-Appenine sandstone of Waidhofen in Lower Austria, of Monte Ferrato, near Prato, Impruneta, Creboli, &c. in Tuscany, and of Borghetta in Liguria. Veins of serpentine have been detected by the geologists of Scotland, in the old red sandstone of Forfarshire.

Some of these masses present characters illustrative of an igneous and violent origin, and throw light on the true situation and formation of other serpentines, whose contaet with neighbouring rocks either has been but imperfectly seen, or not seen at all. The serpentine of Willendorf is a fine example of the injection of this rock amongst older strata. It is situated about half a mile to the west of that village, and on the right hand side of the road leading to Granbach. The limestone hills are bordered by reddish precipices, in the midst of which, the geognost sees with astonishment a thick columnar mass of serpentine rising through the limestone, to the height of 100 feet, and fairly terminating in the surrounding limestone rock. This mass is 60 feet broad below, 40 feet broad at top, has an undulating contour, and a blackish knotted surface, as if composed of irregular spherical bodies. · Small veins of asbestus and calcarequs spar are contained in it, but no distinct diallage rock. It is intimately united with the transition magnesian limestone which it intersects; and between the two rocks there is a breccia composed of a mixture of the limestone and serpentine. Even the limestone itself is impregnated with serpentine matter. All the neighbouring rocks are more or less vesicular, and deeply

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