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day. In grander mountains, such as the Himalayas and Andes, they are found of much greater size; while in Greenland and the Antarctic Continent, the whole surface of the country is completely covered, two thousand to three thousand feet deep, with an ice sheet, moulding itself on the inequalities of surface, and moving slowly seaward, to break off there into masses which form icebergs. The icy, instead of snowy, condition of glaciers, is the result of pressure, together with successive thawings and freezings. Snow is thus slowly compacted into glacier-ice.

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Although glaciers are in continual motion downward, yet the lower end, or foot, never reaches below a certain point; and under unchanging conditions, this point remains fixed. The reason is obvious. The glacier may be regarded as being under the influence of two opposite forces; the downward motion tending ever to lengthen, and the melting tending ever to shorten it. High up the mountain the motion is in excess, but as the melting power of the sun and air increases downward, there must be a place where the motion and the melting balance each other. At this point will be found the foot. called the lower limit of the glacier. Its position, of course, varies in different countries, and may even reach the sea coast, in which case icebergs are formed. Annual changes of temperature do not affect the position of the foot of the glacier, but secular changes cause it to advance or retreat. ing periods of increasing cold and moisture, the foot advances, pushing before it the accumulating debris. During periods of increasing heat and dryness, it retreats, leaving its previously accumulated debris lower down the valley. But whether the foot of the glacier be stationary or advancing or retreating, the matter of the glacier, and therefore all the debris lying on its surface, is in continual motion downward. Since glaciers are limited by melting, it is evident that a river springs from the foot of every glacier.

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Moraines. On the surface, and about the foot of glaciers, are always found immense piles of heterogeneous debris, consisting of rock fragments of all sizes, mixed with earth.

These are called moraines. On the surface, the most usual form and place is a long heap, often twenty to fifty feet high, along each side, next the bounding cliffs. These are called lateral moraines. They are ruins of the crumbling cliffs on each side, drawn out into continuous line by the motion of the glacier. If glaciers are without tributaries, these lateral moraines are all the debris on their surface; but if glaciers have tributaries, then the two interior lateral moraines of the tributaries are carried down the middle of the glacier as a medial moraine. There is a medial moraine for every tributary. In complicated glaciers, therefore, the whole surface may be nearly covered with debris. All these materials, whether lateral or medial, are borne slowly onward by the motion of the glacier, and finally deposited at its foot in the form of a huge, irregularly crescentic pile of debris known as the terminal moraine. If a glacier runs from a rocky gorge out on a level plain, then the lateral moraines may be dropped on either side, forming parallel debris piles, confining the glacier.

Laws of Glacial Motion.-Glaciers do not slide down their beds like solid bodies, but run down in the manner of a body half solid, half liquid; i. e., in the manner of a stream of stiffly viscous substance. Thus, while a gla. cier slides over its bed, yet the upper layers move faster, and therefore slide over the lower layers. Again, while the whole mass moves down, rubbing on the bounding sides, yet the middle portions move faster, and therefore slide on the marginal portions. Lastly, while a glacier moves over smaller inequalities of bed and bank like a solid, yet it conforms to and moulds itself upon the larger inequalities like a liquid. Also, its motion down steep slopes is greater than over level reaches. Thus, glaciers, like rivers, have their narrows and their lakes, their rapids and their stiller portions, their deeps and their shallows. In a word, a glacier is a stream, its motion is viscoid, and for the practical purposes of the geologist, it may be regarded as a very stiffly viscous body.

Glaciers as a Geological Agent.-Glaciers, like rivers, wear away the surfaces over which

they pass; transport materials, and deposit fore, large, angular boulders, different from them in their course or at their termination. the country rock, and especially if in inseBut in all these respects the effects of glacial cure positions, are very characteristic of gla action are very characteristic, and cannot be cial action. mistaken for those of any other agent.

Erosion. The cutting or wearing power of glaciers is very great; not only on account of their great weight, but also because they carry, fixed firmly in their lower surfaces, and therefore between themselves and their beds, rock fragments of all sizes, which act as their graving tools. These fragments are partly torn off from their rocky beds in their course, but principally consist of top-debris, which finds its way to the bottom through fissures, or else is engulfed in the viscous mass on the sides. Armed with these graving tools, a glacier behaves toward smaller inequalities like a solid body, planing them down to a smooth surface, and marking the smooth surface thus made with straight parallel scratches. But to large inequalities it behaves like a viscous liquid, conforming to their surfaces, while it smooths and scratches them. It moulds itself upon large prominences, and scoops out large hollows, at the same time smoothing, rounding, and scoring them. These smooth, rounded, scored surfaces, and these scooped-out rock-basins, are very characteristic of glacial action. We have passed over many such smooth surfaces this morning. The scooped-out rock-basins, when left by the retreating glacier, become beautiful lakes. Lake Tenaya is probably such a lake.

Transportation. The carrying power of river currents has a definite relation to velocity. To carry rock-fragments of many tons' weight requires an almost incredible velocity. Glaciers, on the contrary, carry on their surfaces with equal ease fragments of all sizes, even up to hundreds of tons weight. Again, boulders carried by water currents are always bruised and rounded, while glaciers carry them safely and lay them down in their original angular condition. Again, river currents always leave boulders in secure position, while glaciers may set them down gently by the melting of the ice, in insecure positions, as balanced stones. There

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Deposit: Terminal Moraine.-As already seen, all materials accumulated on the face of a glacier, or pushed along on the bed beneath, find their final place at the foot, and, therefore form the terminal moraine. glacier recedes, it leaves its terminal moraine, and makes a new one at the new position of its foot. Terminal moraines, therefore, are very characteristic signs of the former position of a glacier's foot. They are recognized by their irregular, crescentic form, the mixed nature of their materials, and the entire want of stratification or sorting. Behind the terminal moraines of retired glaciers accumulate the waters of the river that flows from its foot, and thus, again, form lakes. Glacial lakes—i. e., lakes formed by the action of former glaciers-are, therefore, of two kinds, viz: 1, The filling of scooped-out rock-basins; 2, The accumulation of water behind old terminal moraines. The first are found, usually, high up; the second, lower down the old glacial valleys.

Glacial Epoch in California.—It is by means of these signs that geologists have proved that at a period very ancient in human, but very recent in geological chronology, glaciers were greatly extended in regions where they still exist, and existed in great numbers and size in regions where they no longer exist. This period is called the Glacial Epoch. Now, during this Glacial Epoch, the whole of the high Sierra region was covered with an ice-mantle, from which ran great glacial streams far down the slopes on either side. We have already seen evidences of some of these ancient glaciers on this, the western slope. After crossing Mono Pass, we shall doubtless see evidences of those which occupied the eastern slope. In our ride, yesterday and today, we crossed the track of some of these ancient glaciers. From where we now sit, we can follow with the eye their pathways. A great glacier (the Tuolumne Glacier) once filled this beautiful meadow, and its icy flood covered the spot

where we now sit. It was fed by several tributaries. One from Mount Lyell, another from Mono Pass, and still another from Mount Dana, which uniting just above Soda Springs, the swollen stream enveloped yonder granite knobs, five hundred feet high, standing directly in its path, smoothing and rounding them on every side, and leaving them in form like a turtle's back; then coming further down overflowed its banks at the lowest point of yonder ridge—one thousand feet high-which we crossed this morning; and after sending an overflow stream down Tenaya Cañon, the main stream passed on down the Tuolumne Cañon, into and beyond Hetch-Hetchy Valley. From its head fountain, in Mount Lyell, this glacier may be traced forty miles.

The overflow branch which passed down the Tenaya Cañon, after gathering tributaries from the region of Cathedral Peaks, and enveloping, smoothing, and rounding the grand granite knobs which we saw this morning just above Lake Tenaya, scooped out that lake basin, and swept on its way to the Yosemite. There it united with other streams, from Little Yosemite and Nevada Cañons, and from Illilouette, to form the Great Yosemite Glacier, which probably filled that valley to the brim, and passed on down the cañon of the Merced. This glacier, in its subsequent retreat, left many imperfect terminal moraines, which are still detectible as rough debris piles just below the meadows. Behind these moraines accumulated water, forming lakes, which have gradually filled up and formed meadows. Some, as Mirror Lake, have not yet filled up. The meadows of Yosemite, and the lakes and meadows of Tenaya Fork, upon which our horses grazed while we were at "University Camp," were formed in this way. You must have observed that these lakes and meadows are separated by higher ground, composed of coarse debris. All the lakes and meadows of this high Sierra region were formed in this way. The region of good grazing is also the region of former glaciers.

Erosion in High Sierra Region.-The erosion to which this whole high Sierra region

has been subjected, in geological times, is something almost incredible. It is a common popular notion that mountain peaks are upheaved. No one can look about him observantly in this high Sierra region and retain such a notion. Every peak and valley now within our view-all that constitutes the grand scenery upon which we now look— is the result wholly of erosion-of mountain sculpture. Mountain chains are, indeed, formed by igneous agency; but they are afterwards sculptured into forms of beauty by rain. But even this gives as yet no adequate idea of the immensity of this erosion. Not only are all the grand peaks now within view, Cathedral Peaks, Unicorn Peak, Mount Lyell, Mount Gibbs, Mount Dana, the result of simple inequality of erosion, but it is almost certain that the slates which form the foothills, and over whose upturned edges we passed from Snelling to Clark's, and whose edges we again see, forming the highest crests on the very margin of the eastern slope, originally covered the granite of this whole region many thousand feet deep. Erosion has removed it entirely, and bitten deep into the underlying granite. Now, you are not to imagine that the whole, but certainly a large portion of this erosion and the final touches of this sculpturing, have been accomplished by the glacial action which I have endeavored to explain.

About 9 P. M., our clothing still damp, we rolled ourselves in our damp blankets, lay upon the still wet ground, and went to sleep. I slept well, and suffered no inconvenience.

To any one wishing really to enjoy camp-life among the high Sierras, I know no place more delightful than Soda Springs. Being about nine thousand feet above the sea, the air is deliciously cool and bracing, and the water, whether of the spring or of the river, is almost ice-cold and the former is a gentle; tonic. The scenery is nowhere more gloriAdd to this, inexhaustible pasturage for horses, and plenty of mutton, and trout abundant in the river, and what more can pleasure-seekers want?

ous.

Joseph Le Conte.

THE WILLOW TREE.

WILLOW TREE, O Willow Tree,
Why cast down so utterly?

Earth's heart freed from frosty rest
Beats beneath her grassy breast,
And the warm blood of her veins
To thy topmost limb attains;
Sky is blue with June-the sun
Thrills each other leafy one.
Sunlight chiding shunneth thee,
Willow Tree, O Willow Tree !

Willow Tree, O Willow Tree,
Thine is silent threnody.
Speechless motion of thy leaves
On the grass a darkness weaves.
Men are dreamers of a dream,
Life is myth, and fate supreme,
Earth a mound-scarred tomb to thee,
Willow Tree, O Willow Tree !

Willow Tree, O Willow Tree,
I inhale thy sympathy.

I did lay a loved form low
'Neath the frozen turf and snow.
Lids like fringéd petals drew
Close for aye o'er hearts of blue.
Smiles that lit her latest breath
Lingered on in waxen death.

I became like unto thee,
Willow Tree, O Willow Tree!

Willow Tree, O Willow Tree,

Peace to futile elegy!
Winter's day of anguish done,
Sky is blue with June-the sun
Brings new blossoms where the blast
Rent the dead leaves of the past.
June doth stir my sluggish blood,
Life again with hopes shall bud;
All my grief I bury deep
In thy drooping, sunless sleep.

Alas, I shall come oft to thee,
Willow Tree, O Willow Tree!

Wilbur Larrenn

THE WYOMING ANTI-CHINESE RIOT.

It is not the purpose of this article to excuse the recent assaults upon Chinamen in Wyoming, and those threatened in Washington Territory. It is repugnant to the sense of justice of Americans, as it is to their humanitarian ideas, to make the individual suffer for the inconvenience or disasters produced by the masses. The number of persons who have taken pleasure in the annoyance of individual Chinamen in California, or have contributed to it, is comparatively very small, while the number of those who seriously deprecate the influx of this race, and seek to resist it, is overwhelming. It does not follow, as some of our Eastern critics seem to believe, that because the Pacific Coast people are nearly a unit against Chinese immigration, and demand of the national government adequate measures to prevent it, they are ready with the bowie knife and torch to massacre and expel the Chinamen now in their midst. On the contrary, there would probably be as large a vote cast against such illegal violence upon the Chinese, if occasion offered, as there has heretofore been, and would again be, cast for their permanent exclusion. There is no necessary connection between acts of cowardly aggression upon Chinamen, and earnest opposition to the influx of this race to our shores. In fact, the clear-sighted opponents of Chinese immigration see that every criminal act of oppression of this people tends to excite sympathy for them in Eastern circles, and furnishes arguments deemed to be conclusive by a class of minds, why legislative measures to keep them out should be defeated.

An Eastern senator, eminent for ability and personally very estimable, recently took occasion to speak bitterly of the late assault upon Chinese in Wyoming, and to class the opposition to the incoming of this people therewith. From the imperfect report of the speech of the gentleman in question that has reached the writer, this seems to have

been its tenor; and this inference is supported by formerly expressed views of the orator on the floor of the United States Senate. It would probably be impossible to convince Mr. Hoar that the vast majority of the people of the Pacific Coast, who contest Chinese immigration inch by inch by lawful means, detest as bitterly as any of his auditors could any personal assaults upon them. Yet this is true; and our Eastern legislators can never comprehend this question until they are able to draw a distinction between the desire of this people to peacefully and lawfully extirpate a great evil, as they see it, and the reckless and unthinking impulse of a minority, that is impatient under Chinese absorption of its means of livelihood.

It is true that such peaceful and lawful opposition to Chinese immigration is considered to be in itself an offense by our radical opponents; differing only in degree, not in kind, from the crimes of violence to which we refer. It is unreasonable and unjust hostility to the bettering of the condition of a part of the human family! It is in defiance of God's law, who has "made of one blood all the nations of the earth!" It is contrary to the traditions of the fathers of the republic, who made this land the home of the oppressed of all nations! We are, therefore, inhuman, irreligious, and unpatriotic, because we would exclude the Chinese; and what more are those who put the torch to the hut of the Chinaman, and shoot him as he flees over the hills? These prepossessions against us seem to those holding them to be grounded so deeply upon principle, that any argument drawn from the peculiarities of the Chinese, their modes of life and acting, their propagation of disease and bad morals, their absorption of the means of living, and exclusion of white labor from employment, their unassimilability to the American, their continuance as strangers in the land after years of residence, their entire want of characteris

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