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of the land and dropped upon that surface as it retreated. The result is that in all countries which were affected by the last glacial period, the river-valleys have only here and there, and in all cases imperfectly, returned to their ancient beds. Ever since the ice went away, they have been engaged in a struggle to restore their ruined ways. As yet, this work is most imperfectly accomplished, and even if a glacial period should not return to the northern part of North America for several million years, the task of restoring the river systems to their original aspects would not be completed.

We see a simple indication of this confusion of the old drainage brought about by glacial action in the vast number of lakes lodged within depressions of the surface in New England as well as in all parts of the glaciated district. We have only to compare the valley of such a stream as the James River, which lies south of the glacial belt, with a New England valley, such as that of the Merrimac, to see the importance of the effects accomplished by a glacial sheet on the river-system. The valley of the James is entirely without lakes; every part of its area slopes downward toward the sea. In the valley of the Merrimac, there are hundreds of these water-basins. A very large part of its surface is occupied by lakes, which owe their origin to irregularities of the surface, produced by the last glacial period. There is yet another way in which rivers may be naturally obstructed; this is by lava-streams pouring out into their valleys. In all volcanic regions, the river-beds are apt to receive great inundations of such material. When gigantic eruptions of lava, such as have occurred in the recent geological periods in Oregon and California, in Southern India, and in Eastern Europe, are poured out, the stream-beds are apt to be gorged with this igneous material, it may be for a distance of a hundred miles from the volcanic vents. At first the river is dried up by the fiery torrent; when the lava cools it becomes solid, often much more resisting to water-action than the rocks originally underlying the stream. It generally happens that the lava-current is higher in the middle of its course than

it is upon the margin. The result is that when the river begins again to flow its course is divided into two, part of the water flowing on either side of the lava-stream. As time goes on and the streams cut deeply into their new beds, they may leave the old lava-mass perched upon a hill, as shown in the diagram, [p. 147.] It happens in California that these streams occupied by the lava contain gold-bearing sands, sometimes in very large quantities. The deposits of gold were accumulated before the lava came into the ancient river-beds. Miners have learned that wherever a mass of lava occupies the position indicated in the diagram they may reasonably expect, by excavating through the side of the hill, to strike the old river-channel, and beneath the cap of lava, to find large deposits containing gold, which they may win more easily than the deposits in the beds of the existing streams. Owing to the extensive explorations which have been made in this search for gold in such positions, we have gained some very important information from these obliterated, encumbered river-beds.

Perhaps the oldest evidences which we have of pre-historic man have been obtained from these mines driven into the ancient channels of rivers on the Pacific coast. A number of rude stone implements have been disinterred by these mining operations, which clearly prove that the region was extensively occupied by man. One human skull has also been found in these workings, along with the remains of several extinct animals. The streams flow on either side of the old lava-current, and as they cut but slowly into the subjacent rock, we are able with safety to infer that these remains of man have been in existence for twenty thousand years or more. In Central France, near by the town of Le Puy, similar lavastreams also contain buried human remains. In both these cases, the remains of man have been found associated with those of extinct animals; which fact serves to show that the conclusion we draw as to the antiquity of man from the erosion which has taken place since the lava-current flowed is well founded.

Although the rivers have to maintain a battle with many obstructing actions due to natural causes, there are only two

circumstances derived from the revolutions of the earth's surface which seriously affect their history, at least in a permanent way. Where the rainfall of a country undergoes considerable variations, as appears always to be the case in the course of long geological periods, the streams necessarily find their volumes diminished or increased, sometimes in an important degree. However much the rainfall may vary, the architecture of a river, the position of its branches, the distribution of its torrent and alluvial sections generally remain essentially unchanged. Even where the continent on which a river lies is greatly elevated beyond its original height, the system of the streams remains as it was before. Thus our rivers are in many cases the oldest features on the earth's surface. The upper waters of the Tennessee, for instance, especially those of the French Broad River, have apparently endured since the earliest ages of which we have any distinct record in the great stone book. They seem to have flowed at the beginning of the Cambrian time, and their channels have borne their floods to the sea during periods in which the continent of North America has undergone vast changes in form. Certain groups of fishes, such as the gar pikes, which probably had their cradle in these waters, have apparently dwelt in them continually since the Devonian time.

The only conditions which actually lead to the destruction of a river-system arise either from the imposition of a glacial sheet on the surface of a country or from its submergence beneath the level of the sea. We have already seen that the interruption brought about by a continental glacier on the streams in the country over which it extends is usually but temporary. In a like manner, the submergence of a great valley beneath the sea-level is not apt entirely to destroy its basin. When the surface of the continent recovers its position, returning to the state of dry land, there is generally enough left of the form of the basin to cause the stream, at least in a general way, to follow its ancient paths. With the foregoing brief sketch of their mechanism, we will turn our attention to the relations between the civilization of man and the system of the rivers.

Nowhere else in the physical machinery of our earth is the influence of the hand of man so well shown as in the conditions of rivers. Nowhere else are his destructive or conservative powers so important. The effect of man's action upon rivers is in the main due to the fact that his occupancy of the earth leads to the removal of its forest covering. We have already incidentally noted the relation of trees to the immediate bounds of a stream; we have seen that the woods are continually pressing upon the margins of a river, causing it to sway to and fro, and tending always to narrow its channel. This is only one, and perhaps the least important, of the effects exercised by forests on the regimen of the greater streams. It is necessary to consider the action of forests over the whole basin of a river, in order to see the magnitude of their influence on the action of these waters.

The valleys of most rivers are forestclad. Whether these forests have the gigantic growth characteristic of fertile districts in the tropics and the temperate zones, or take the shape of stunted woods, such as extend far toward the poles, they in all cases form beneath their branches, and above the soil, a thick, spongy coating, which affords a natural reservoir for the rain waters. In most regions, this forest-sponge has a depth of more than a foot; it not infrequently attains a thickness of two feet or more. It can commonly take into its interstices a rainfall of three or four inches in depth, or from one-sixth to one-tenth the ordinary annual supply. This water is slowly yielded to the brooks; it often requires weeks for a single torrential rain entirely to escape into the open channels which bear it to the sea. Moreover, the fallen trunks and branches of the trees clog the forest-shaded rivulets, making little pools, which serve still further to restrain the outgoing of the waters. Our beavers, at one time the most widely distributed of our larger animals, at first making avail of these natural ponds formed by fallen timber, learned in time to construct more artful dams so as to retain extensive basins of water. Thus, in the natural condition of the North American rivers, as well as those of most other

countries before man began to clear away the forests, the woods constituted a great system of reservoirs, in which the rains were retained into the period of intervening droughts. In this state of the surface, the main channels of a river-system were continually the seat of streams of moderate flow. These channels were no wider than was required by the rate at which these forestimpounded waters escaped.

When man resorted to the soil as the source of his food, he began to clear away the forests and by tillage to destroy the spongy covering of the earth which they created. With the advance of civilization, all the great valleys on the northern temperate zone have been to a considerable extent deprived of their forest covering. In this new state of the surface, the rain-water is no longer held back as it was of old, but flows quickly over the surface of the soil and enters the water-ways. The result is that all the old channels bear, in times of flood, a body of water far greater than that which was put into them before the forests were cleared away. They have been compelled to widen their channels by cutting away a strip of the alluvial land on either side. Thus, in the case of the Ohio River, the bed occupied by the flood-waters has, since the beginning of the present century, been widened to the amount of about one-fifth of its total diameter. Despite this widening, it is now unable to bear away the floodwaters yielded to it by the extensive tilled surfaces of its basin. In times of flood it rises higher than of old and spreads devastation over a wider area of the alluvial plains. In times of drought the stream shrinks within its waste of encumbering sands and becomes unnavigable.

In the present condition of the Mississippi Valley, these floods and droughts seriously affect the interests of man. There, as in all other civilized countries, the great seats of population tend to gather on the river-banks. The alluvial lands are in all cases singularly fertile; and the streams themselves afford natural ways of transportation, the value of which does not seem to become lessened by the great extension of railway systems. In the present condition of these

valleys, the fitness of these streams for navigation is progressively diminishing, for both in times of flood and in periods of drought they are unsuited to the uses of commerce. Moreover, in the flood periods, the streams are a very serious menace to all the towns which are gathered along the river-banks. As yet, we have only seen the beginning of these evils; for notwithstanding the extensive settlements in the Mississippi valleys, more than half their original forest covering remains. When, with the rapid increase of population, these river-basins become as thoroughly subjected to the uses of man as are those of Europe, we have yet greater ills to apprehend.

The problem of the Mississippi Valley is one of national importance. By far the greater part of the food-producing capacity of our continent lies in the basin of that great system of rivers. It is therefore worth our while to consider the method by which this area can best be brought to serve the needs of man without imposing a serious burden on his arts. Although it is impossible in these few pages to consider the way in which this great task may be accomplished, it is perhaps worth while to note the general conditions which have to be met in this and other great valleys if that end is to be secured.

In endeavoring to meet the evils which arise from the removal of forestcovering from the surface of a country, we find that the difficulties to be considered are as follows: First, those which arise from the diminished restraint put upon the movements of the water which comes to the earth's surface in times of heavy rain or of melting snow. Next, the evils due to the rapid wasting of the soil, which, in its unprotected condition, is readily washed into the stream-beds. The first of these evils gives rise to serious destruction of wealth and to the interruption of industries. The second threatens the loss of that precious soilcovering on which depends the relation of all land life, that of plants and man and beast, to the surface of the earth. It is clearly evident that we cannot hope to preserve any considerable portion of our forest lands from destruction. The need of subsistence such as is drawn from the soil is immediate and over

whelming. During the last century, Europe has been able to preserve a portion of its forests, and indeed to win extensive areas back to the condition of woods, for the reason that it could draw supplies of food from this country; but when our American soils are occupied, it does not seem likely that other parts of the world will afford any such opportunity for obtaining foreign grain. At most, we may expect that a small area, perhaps not exceeding one-tenth of our original forests, may be retained in their present shape, in order to afford supplies of timber. It is therefore necessary, if we have to control these flood-waters at all, to devise some means by which we may imitate the old natural system of water storage which the primeval woods afforded. There is but one method by which this end may be accomplished, viz.: by creating artificial reservoirs in which the waters may be for a time retained during the period of floods.

Some years ago a distinguished engineer, Mr. Charles Ellet, suggested a system of controlling the floods of the Mississippi Valley. He proposed to build certain dams in the upper waters of the Mississippi system, in which, during the times of flood, a considerable part of the flow might be impounded, to be discharged into the channels at such times as was needed to maintain a navigable depth of water. There are certain objections to the details of the system proposed by Mr. Ellet, the principal of which is that the existence of very large reservoirs would add another source of danger to those which the floods now inflict upon the valleys of these streams. It is difficult to build retaining dams so that they may be absolutely secure from the risks of giving way. The bursting of such a dam in time of flood might prove peculiarly dis

astrous.

It seems, however, possible that a slight modification of Mr. Ellet's plan would more effectively accomplish the end he had in view, without creating the risks above noted. For in place of half a dozen great artificial lakes, we should adopt the plan of having many thousands, or tens of thousands, of smaller reservoirs, so arranged that no one would, by its

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bursting, lead to the destruction of any other. We could by this means retain on the surface of the land a very considerable part of the flood-waters which now prove disastrous to the valleys below. Computations, which it would be out of place to present in a writing of this nature, have shown me that it would apparently be possible, with an expenditure of less than fifty million dollars, to diminish the rise of floods at Cincinnati to the amount of at least twelve feet, and at the same time secure to that river a good degree of navigability during the whole of the dry summer season. control in a similar manner the floods which ravage the valleys of the other large tributaries of the Mississippi, would perhaps require a total expenditure exceeding one hundred million dollars. The maintenance of this system would necessarily be costly; it would perhaps amount to as much as ten million dollars a year. It seems, however, possible that for this cost we might obtain a substantial immunity from the worst destruction accomplished by our floods. Even if this system should be adopted, it would be necessary, decade by decade, as the process of forest removal advanced, to extend still further the area of the storage reservoirs.

While the proper control of the Mississippi drainage system is of great importance to the nation at large; to the States which border upon its waters it is a matter of vital necessity. Whether this great task is to be undertaken by the Federal Government or by associated Commonwealths, there can be no question that it should be at once entered upon. Every year increases the magnitude of the necessities and the difficulty of devising means to meet them.

Although the American theory of government looks to the initiative of the individual for the most of the acts which in other lands are accomplished by the state, it still has to confess that certain classes of work are only accomplishable by federal control. Our great river is fast becoming a common enemy of our people; it is our duty to restrain its ravages as we would those of any other foe of the state.

OTTO THE KNIGHT.

By Octave Thanet.

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UNT BETSEY GRAHAM, who kept the plantation tavern, stood in her wide gallery-way, waiting for the mill whistle to send her boarders to supper. There was not a kinder woman in Lawrence County, or, in a homely fashion, a better cook.

Look at her, now, in the shadow of the old-fashioned porch, built when bears were shot in the cypress brake; her portly form is clad in a red and black striped cotton gown and white apron; her gray hair is thick like a girl's, her little brown eyes twinkle jovially, the hardy late roses bloom on her tanned cheeks, and nobody on the plantation has such beautiful, white store teeth.

She sees the road, a broad, then a narrow, then a fading streak of yellow, cutting the cotton-fields and defining the borders of the brake. Some of the houses which she sees are trig and painted; some have crooked, dark roofs, and chimneys bulging sidewise against black-gray walls. It is the old South and the new. Looking obliquely to the right, she sees the smithy under its great "water oaks," and, almost at right angles, the carpenter shop and the gaunt black shape of the old mill. Further down the river bank is the new mill, which has men crawling over its roof and rings with the click of hammers.

But soon Aunt Betsey's eyes returned to Otto Knipple, splitting wood just in front of the porch. She thought, sorrowfully, that he would never make out with that hickory; but what could you expect of a boy raised in St. Louis and come down to the Black River with those ornery, trifling St. Louis carpenters?

Otto was a scrap of a lad, carrying a premature age in his sallow, care-worn, eager little features, that were the sallower and more eager for his mat of

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"Oh, sorter like the Ku-Klux?"

"Oh no, mum, not a bit like the KuKlux. They are all good men and they shall make all the poor people own their own property and Uncle Bruno kin come home at four o'clock

"Sekrit soci'ty, hey?"

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They've got to be, mum; 'cause else them bloated capitalists would find out all their plans."

"That 'ar sounds powerful like KuKlux," said Aunt Betsey critically. "They all was mighty biggity, but I never seen nuthin' come er thar braggs 'cept folkses ketchin' cole, romancin' roun' nights, by the dark of the moon. I know all 'beout them sekrit soci'ties. I read a book 'beout 'em, oncet. Thar was a man taken a oath on a skull wilst two men hilt dadgers over him iz was dreepin' with jore. Warn't that orful?"

"Yes, mum, please go on!" cried Otto, revelling in the lurid picture.

"By the fitful glem er a dyin' lamp," Aunt Betsey continued. "Must of ben one er them grease lamps, they're allers devilin' someway. I disremember jes whut 'twas he swore, but I know his ha'r, iz was black like the ravin's wing, turned plum w'ite in a single night. His folks

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