1864.] About Glaciers. rier that dams it, gushing out profusely in whitish-blue streams from the icegrots, which it has excavated in some instances to the height of a hundred, and the breadth of from fifty to eighty feet, and which present a romantic variety of picturesque scenes. Nor do the waters form the only element in action on this awful stage. A change of temperature liberates the glacier-blast, the gletschergeblase of the Germans, from its frozen cavity; and the rushing bitter cold air-current escapes from the crevasses, driving the frost motes like snow-dust before it, and insupportable as the sarsar, the icy wind of death. It may be stated as a general proposition, that all the Alpine valleys are inclined planes. Down these the glaciers must slip by their own weight whenever any cause loosens their adhesion to the sides and bottom of those valleys. The warmth of the earth contributes to the diminution of this adhesion by thawing the under surface of the glacier. This, however, takes place in those parts only where the great thickness of the ice shields the ground from the operation of external cold; and the mass, consequently, being only partially disengaged, maintains its position. But where the penetrating rays of the summer's sun have diffused a general circumjacent heat, the ice is thawed at its surface and edges; then the liberation of the glacier is rapid, aided as it is by the erosion of the underflowing currents, and the abrasion of the ice and stones which those cur rents bear along, and the whole mass, The glacier's cold and restless mass Or with its ice delay. 45 If there were no compensation, there would be, notwithstanding the great waste arising from the causes above mentioned, a great increase in the glaciers; because the winter accession of snow and ice would largely predominate over the loss occasioned by summer and other heat. But this is a compensating world, and, as far as human memory and observation have gone, it has been found that there is no sensible increase. If during one, or even during a few, succeeding years, some of the glaciers are observed to descend unusually low, in the following years they are found to recede in proportion. Above, evaporation from the snow and ice is going on to a large extent even in winter, and with great rapidity in the dry and rarified air; below, subterranean heat is at work. But all the summer, winter, and subterranean causes would be inadequate to prevent a gradual but slow increase of the ice, if it were not for the steady slow march of the glaciers into the lower valleys, where they have to encounter a warm atmosphere. The greater the increase arising from the accumulations of the preceding winter, the greater becomes the pressure from above, and the further the glacier descends into the region of thaw. The lower it slips down, the greater is the space left behind to be filled up, and the greater must be the time required before further accumulation pushes the mass forward. this time the lower extremity subjected Thus is to the heat, recedes as much at least as it had advanced, if not more. the equilibrium kept up; and thus are the cultivated lands of the lower valleys protected from excessive encroachment. All Glaciers, like other invading forces, have their adjuncts. Masses of débris accumulate in the shape of long dykes or parapets along the anterior edge and lateral margins of some of the larger examples. These are the moraines of the Savoyard, the trockne muren of the Tyrolese, and the jokülsgiärde of the Icelander, to whom the glaciers are known under the name of jokül. The Savoyard exist. In the lower valleys they are name generally prevails. Moraines are thus formed. Schistose or stratified rocks, free from snow and ice in consequence of their slope, but bordering the glaciers, are exposed to all the atmospheric influences. Gradually disintegrated by the alternations of humidity and frost, heat and cold, their detached fragments roll down to the lateral edge of the glacier, where the greater part is, in sailor's phrase,' 'brought up;' while some blocks are protruded onwards towards the middle. By the general inclination of the glacier and its downward progress, a quantity of these débris are collected along the anterior termination of the ice-field. Thus, in some cases, the whole glacier becomes surrounded by a moraine. But wherever mountain-slopes are protected by what we have heard termed their private glacier, or where the rock is composed of compact and all but indestructible granite, there is no moraine. And thus it happens that on each side of some glaciers a moraine will be found; others present a moraine on one side only; and some none at all. Again, a moraine is sometimes found where it could not have been formed. In such cases the nature of the débris shows that it must have been brought down from a higher station by the motion of the glacier. The height of moraines varies; some reach an altitude of one hundred feet. As a general rule it will be found that, when the glaciers have undergone diminution, the moraine is above the ice; but in those cases where they have increased, the moraine is lower than the ice-field. In others the moraine and the ice are on a level. found in succession at altitudes as high as twelve, fifteen, and even eighteen hundred feet. In the neighborhood of St. Maurice they occur at two thousand feet above the bed of the Rhone; and they may be traced at a great height round the lake of Geneva. From such facts and other data, Agassiz comes to the sweeping conclusion that at one time the whole of the plains of Switzerland were covered by glaciers to a height of three thousand three hundred feet above the level of the sea, or two thousand one hundred and fifty-five feet above the present surface of the lake of Geneva, and that they extended as far as the Jura. To support this grand theory, which requires him to account for the existence of such immense masses of ice, he supposes the alternate heating and cooling of the globe at distant but given periods, appeals to fossil remains, and endeavors to explain the erratic blocks of the Jura by viewing them as the transported moraines of his enormous glaciers. But, besides the fringing or bordering moraines, glaciers sometimes exhibit central banks, and long and high ridges composed of fragments of rocks, boulders, sand and earth, at some distance from the margins, to which, however, they generally run parallel. These, the guferlinien of the German-Swiss cantons, are sometimes numerous and high. De Saussure crossed four or five of them, thirty or forty feet high, in traversing the great ice-field above Montanvert. This elevation is due partly to the quantity of debris, and partly to the sinking of the surrounding ice which thaws, while that sheltered from the sun under the heap remains unthawed. Rosboden glacier is rich in the number and dimensions of these ridges. The following is the explanation given of the formation of these banks: Slipping down upon the inclined bottom of the valley, the glacier recedes from the side, carrying with it and upon it part of the lateral moraine. This operation often leaves a considerable space, in the wider valleys especially, between the foot of the mountains and the edge of the glaciers, and this space, -during the succeeding winter, is filled up with fresh snow which is converted into ice, and on which a new moraine is accumulated. This in its turn recedes like the first, and is succeeded by others, so that if it did not happen that the moraines of the opposite sides are sometimes confounded into one, and that the motion of the ice on the irregular slopes of the valley disturbs the order and parallelism of the banks, they might serve as marks to determine the age of the glaciers. Whatever may be thought of the grand notion of M. Agassiz, enough of ice remains in the shape of glaciers. Those of the Tyrol, Switzerland, Piedmont, and Savoy, present a superficial extent which has been calculated at fourteen hundred and eighty-four square miles. Some of them are from ten to fifteen miles in length, and from one to two miles and a quarter in breadth, and some attain a thickness of from one to six hundred feet. In these icy reservoirs the copious supplies of the principal European rivers are contained. The Pyrenees and the Sierra Nevada have glaciers, nearly all of which occur on the northern slopes; and here we may observe that the evidence indicates but few glaciers in the direction of east and west. In the north, Spitzbergen, Iceland, and Greenland, present numerous and magnificent glaciers; and though it seems to be the general opinion that they are formed in the same manner as those of the Alps, the superior compactness and beautiful transparency of the northern examples, and of the icebergs detached from them, are universally acknowledged. The glaciers of the south-west coast of America, the Strait of Magalhaens, and Tierra del Fuego, are extensive. If we turn to Upper Asia we are struck with the extensive range of the Altai mountains forming its northern border. The formation and motion of their glaciers appear to be the same with those of the European Alps; and those who study the subject will not find much variance between the observations of Gebler and De Saussure. To enumerate all who have contributed to the stock of information on this interesting subject would border upon the endless. The names of Henderson and Graah will immediately occur to the initiated reader in connection with Iceland and Greenland, and of Forbes with those of Norway. THE green of the turf old Erin doth show, In the shades of that pure and exquisite green We have seen a birth and burial in the deadest watch of night; We saw our old friend failing at the twilight of the year, When the trembling trees shook off their robes to cover o'er his bier, And the wailing winds of Winter, and the tearful clouds were here, To sorrow o'er his tomb. As the savage chief is buried with his hunting-knife and gun, We have placed the old king's record in the open hands of Time; O the bonds of Truth unwritten! O the marks of fraud and crime ! Time has handed up the book to HIM to whom the hours belong; In the narrow reign behind us, for the lifeless love of pelf, We have martyred Truth and Justice, and have scorned each better elf. Let us all before we stumble grasp His mighty hand once more; ON LOOKOUT MOUNTAIN. BY LIEUTENANT WILLIAM L. ENGLISH, ONE HUNDRED AND FIRST ILLINOIS INFANTRY. But A CAMP at best is but a dull place, full of monotony and sameness. when there are numerous companions around, one possessed of a social disposition can contrive to while away the time not passed on duty with some de gree of pleasantness. But to be left behind, while the regiment or brigade is off on a march, with only two or three companions, selected on account of illhealth, is extremely irksome. The days seem long, very long, and the only pleasure consists in going to bed at night, if any thing that we are fortunate enough to possess can be dignified with the name of bed. Worn out with this monotony, a party of us concluded, one day, to visit the peak of Lookout Mountain, whence 'Fighting Joe Hooker' had just compelled the rebels to exhibit their prowess in the art, somewhat familiar to them, of 'skedaddling.' It was a beautiful Sabbath morning, somewhat cool, but bright with pleasant sunshine. We first went along the railroad for nearly half a mile, until we crossed Lookout Creek, which washes the foot of the mountain; then we turned our course up the slope of the mountain, winding our way for some distance amid the rocks and huge boulders that we had often mistaken for rebel tents. Some of these boulders could not have been less than forty feet in perpendicular height, and possessed sufficient bulk to have furnished stone enough for several large houses. Passing by these, we soon gained the crest of the slope running down to the river, just at the point where a rebel masked battery had been, which, however, never had much opportunity to prove its efficacy, owing to the suddenness of our attack and the complete capture of the rebel brigade 4 VOL. LXIL which held the western slope of the mountain. Leaving the battery to our left, we climbed a little higher, and came to a road, which we followed around the point until we reached a large shelf, where we found a fine farm-house. There is a splendid spring lodge, made of rock, connected with it. I took a drink out of the large rock basin, and it was cool and refreshing, better far than any draught of champagne or sherry ever made. Resting here for a while, we nerved ourselves for the grand slope, which has at least an inclination of about forty-five degrees. We pulled ourselves along, however, stopping occasionally to hold our hands over our ears, for the keen, cold air fairly made them tingle. At last we reached the top of the slope, and here a perpendicular wall of rock stared us in the face. Passing, however, around the point, along the western side, we soon found a ladder, which we scaled and then stood on the crest of Lookout Mountain. We passed out to the edge of the rock, and gathered some pine boughs for relics. I cut a nice cane, and some of us gathered laurel-root, from which to whittle out pipes. I have seen several very fine pipes, made of laurel-root, gathered on the mountain, and provided with neat cherry stems, cut from the trees that surround the farm-house. The atmosphere was somewhat smoky, which prevented our enjoying the full extent of the scene, Almost directly in the front is Chattanooga, surrounded by an army of tenantless tents, their late occupants far away in victorious pursuit of Bragg's routed army. To the left, stretching as far as we can see, meanders the beauti |