Puslapio vaizdai

of the land and dropped upon that sur- it is upon the margin. The result is face as it retreated. The result is that that when the river begins again to flow in all countries which were affected by its course is divided into two, part of the last glacial period, the river-valleys the water flowing on either side of the have only here and there, and in all lava-stream. As time goes on and the cases imperfectly, returned to their an streams cut deeply into their new beds, cient beds. Ever since the ice went they may leave the old lava-mass perched away, they have been engaged in a upon a hill, as shown in the diagram, [p. struggle to restore their ruined ways. 147.] It happens in California that these As yet, this work is most imperfectly streams occupied by the lava contain accomplished, and even if a glacial pe- gold-bearing sands, sometimes in very riod should not return to the northern large quantities. The deposits of gold part of North America for several mill. were accumulated before the lava came ion years, the task of restoring the river into the ancient river-beds. Miners have systems to their original aspects would learned that wherever a mass of lava not be completed.

occupies the position indicated in the We see a simple indication of this diagram they may reasonably expect, by confusion of the old drainage brought excavating through the side of the hill, about by glacial action in the vast to strike the old river-channel, and benumber of lakes lodged within depres- neath the cap of lava, to find large desions of the surface in New England posits containing gold, which they may as well as in all parts of the glaciated win more easily than the deposits in the district. We have only to compare the beds of the existing streams. Owing to valley of such a stream as the James the extensive explorations which have River, which lies south of the glacial belt, been made in this search for gold in with a New England valley, such as that such positions, we have gained some of the Merrimac, to see the importance very important information from these of the effects accomplished by a glacial obliterated, encumbered river-beds. sheet on the river-system. The valley Perhaps the oldest evidences which we of the James is entirely without lakes; have of pre-historic man have been obevery part of its area slopes downward tained from these mines driven into the toward the sea. In the valley of the ancient channels of rivers on the Pacific Merrimac, there are hundreds of these coast. A number of rude stone implewater-basins. A very large part of its ments have been disinterred by these surface is occupied by lakes, which owe mining operations, which clearly prove their origin to irregularities of the sur- that the region was extensively occupied face, produced by the last glacial period. by man. One human skull has also been

There is yet another way in which found in these workings, along with the rivers may be naturally obstructed; remains of several extinct animals. The this is by lava-streams pouring out into streams flow on either side of the old their valleys. In all volcanic regions, the lava-current, and as they cut but slowly river-beds are apt to receive great inun- into the subjacent rock, we are able with dations of such material. When gigan- safety to infer that these remains of man tic eruptions of lava, such as have oc- have been in existence for twenty thoucurred in the recent geological periods in sand years or more. In Central France, Oregon and California, in Southern India, near by the town of Le Puy, similar lavaand in Eastern Europe, are poured out, streams also contain buried human rethe stream-beds are apt to be gorged mains. In both these cases, the remains with this igneous material, it may be for of man have been found associated with a distance of a hundred miles from the those of extinct animals ; which fact volcanic vents. At first the riveris dried serves to show that the conclusion we up by the fiery torrent; when the lava draw as to the antiquity of man from the cools it becomes solid, often much more erosion which has taken place since the resisting to water-action than the rocks lava-current flowed is well founded. originally underlying the stream. It Although the rivers have to maintain generally happens that the lava-current a battle with many obstructing actions is higher in the middle of its course than due to natural causes, there are only two

circumstances derived from the revolu- Nowhere else in the physical machintions of the earth's surface which seri- ery of our earth is the influence of the ously affect their history, at least in a hand of man so well shown as in the permanent way. Where the rainfall of a conditions of rivers. Nowhere else are country undergoes considerable varia- his destructive or conservative powers tions, as appears always to be the case so important. The effect of man's action in the course of long geological periods, upon rivers is in the main due to the the streams necessarily find their vol- fact that his occupancy of the earth leads umes diminished or increased, some- to the removal of its forest covering. times in an important degree. However We have already incidentally noted the much the rainfall may vary, the archi- relation of trees to the immediate bounds tecture of a river, the position of its of a stream ; we have seen that the branches, the distribution of its torrent woods are continually pressing upon the and alluvial sections generally remain margins of a river, causing it to sway

to essentially unchanged. Even where the and fro, and tending always to narrow continent on which a river lies is greatly its channel. This is only one, and perelevated beyond its original height, the haps the least important, of the effects exsystem of the streams remains as it was ercised by forests on the regimen of the before. Thus our rivers are in many greater streams. It is necessary to concases the oldest features on the earth's sider the action of forests over the whole surface. The upper waters of the Ten- basin of a river, in order to see the magnessee, for instance, especially those of nitude of their influence on the action the French Broad River, have apparently of these waters. endured since the earliest ages of which The valleys of most rivers are forestwe

have any distinct record in the great clad. Whether these forests have the stone book. They seem to have flowed gigantic growth characteristic of fertile at the beginning of the Cambrian time, districts in the tropics and the temperand their channels have borne their floods ate zones, or take the shape of stunted to the sea during periods in which the woods, such as extend far toward the continent of North America has under- poles, they in all cases form beneath gone vast changes in form. Certain their branches, and above the soil, a groups of fishes, such as the gar pikes, thick, spongy coating, which affords a which probably had their cradle in these natural reservoir for the rain waters. waters, have apparently dwelt in them In most regions, this forest-sponge has a continually since the Devonian time. depth of more than a foot; it not infre

The only conditions which actually quently attains a thickness of two feet lead to the destruction of a river-system or more. It can commonly take into its arise either from the imposition of a interstices a rainfall of three or four glacial sheet on the surface of a coun- inches in depth, or from one-sixth to try or from its submergence beneath one-tenth the ordinary annual supply. the level of the sea. We have already This water is slowly yielded to the seen that the interruption brought about brooks ; it often requires weeks for a by a continental glacier on the streams single torrential rain entirely to escape in the country over which it extends is into the open channels which bear it usually but temporary. In a like man

to the sea.

Moreover, the fallen trunks ner, the submergence of a great valley be- and branches of the trees clog the forneath the sea-level is not apt entirely to est-shaded rivulets, making little pools, destroy its basin. When the surface of which serve still further to restrain the the continent recovers its position, re- outgoing of the waters. Our beavers, turning to the state of dry land, there at one time the most widely distributed is generally enough left of the form of of our larger animals, at first making the basin to cause the stream, at least in avail of these natural ponds formed by a general way, to followits ancient paths. fallen timber, learned in time to con

With the foregoing brief sketch of struct more artful dams so as to retain their mechanism, we will turn our atten- extensive basins of water. Thus, in the tion to the relations between the civiliza- natural condition of the North American tion of man and the system of the rivers. rivers, as well as those of most other


countries before man began to clear valleys, the fitness of these streams for away the forests, the woods constituted navigation is progressively diminishing, a great system of reservoirs, in which for both in times of flood and in periods the rains were retained into the period of drought they are unsuited to the uses of intervening droughts. In this state of commerce. Moreover, in the flood of the surface, the main channels of a periods, the streams are a very seririver-system were continually the seat ous menace to all the towns which are of streams of moderate flow. These gathered along the river-banks. As yet, channels were no wider than was we have only seen the beginning of these quired by the rate at which these forest- evils ; for notwithstanding the extensive impounded waters escaped.

settlements in the Mississippi valleys, When man resorted to the soil as the more than half their original forest coversource of his food, he began to clear away ing remains. When, with the rapid inthe forests and by tillage to destroy the crease of population, these river-basins spongy covering of the earth which they become as thoroughly subjected to the created. With the advance of civiliza- uses of man as are those of Europe, we tion, all the great valleys on the north- have yet greater ills to apprehend. ern temperate zone have been to a con The problem of the Mississippi Valley siderable extent deprived of their forest is one of national importance. By far covering. In this new state of the sur- the greater part of the food-producing face, the rain-water is no longer held capacity of our continent lies in the back as it was of old, but flows quickly basin of that great system of rivers. It over the surface of the soil and enters is therefore worth our while to considthe water-ways. The result is that all er the method by which this area can the old channels bear, in times of flood, a best betbrought to serve the needs of body of water far greater than that man without imposing a serious burden which was put into them before the for on his arts. Although it is impossible ests were cleared away. They have in these few pages to consider the way been compelled to widen their channels in which this great task may

be accomby cutting away a strip of the alluvial plished, it is perhaps worth while to note land on either side. Thus, in the case of the general conditions which have to be the Ohio River, the bed occupied by met in this and other great valleys if the flood-waters has, since the beginning that end is to be secured. of the present century, been widened to In endeavoring to meet the evils the amount of about one-fifth of its to which arise from the removal of foresttal diameter. Despite this widening, it covering from the surface of a country, is now unable to bear away the flood- we find that the difficulties to be considwaters yielded to it by the extensive ered are as follows : First, those which tilled surfaces of its basin. In times of arise from the diminished restraint put flood it rises higher than of old and upon the movements of the water which spreads devastation over a wider area of comes to the earth's surface in times of the alluvial plains. In times of drought heavy rain or of melting snow. Next, the stream shrinks within its waste of the evils due to the rapid wasting of the encumbering sands and becomes unnav- soil, which, in its unprotected condition, igable.

is readily washed into the stream-beds. In the present condition of the Mis- The first of these evils gives rise to serisissippi Valley, these floods and droughts ous destruction of wealth and to the inseriously affect the interests of man. terruption of industries. The second There, as in all other civilized countries, threatens the loss of that precious soilthe great seats of population tend to covering on which depends the relation gather on the river-banks. The alluvial of all land life, that of plants and man lands are in all cases singularly fertile ; and beast, to the surface of the earth. It and the streams themselves afford natu- is clearly evident that we cannot hope to ral ways of transportation, the value of preserve any considerable portion of which does not seem to become lessened our forest lands from destruction. The by the great extension of railway sys- need of subsistence such as is drawn tems. In the present condition of these from the soil is immediate and over

whelming. During the last century, Eu- bursting, lead to the destruction of any rope has been able to preserve a portion other. We could by this means retain of its forests, and indeed to win extensive on the surface of the land a very considareas back to the condition of woods, for erable part of the flood-waters which the reason that it could draw supplies now prove disastrous to the valleys below. of food from this country ; but when our Computations, which it would be out of American soils are occupied, it does not place to present in a writing of this natseem likely that other parts of the world ure, have shown me that it would apparwill afford any such opportunity for ob- ently be possible, with an expenditure of taining foreign grain. At most, we may less than fifty million dollars, to diminish expect that a small area, perhaps not ex- the rise of floods at Cincinnati to the ceeding one-tenth of our original forests, amount of at least twelve feet, and at may be retained in their present shape, the same time secure to that river a in order to afford supplies of timber. good degree of navigability during the It is therefore necessary, if we have to whole of the dry summer season. To control these flood-waters at all, to de- control in a similar manner the floods vise some

means by which we may which ravage the valleys of the other imitate the old natural system of water large tributaries of the Mississippi, , storage which the primeval woods af- would perhaps require a total expendiforded. There is but one method by ture exceeding one hundred million dolwhich this end may be accomplished, lars. The maintenance of this system viz: by creating artificial reservoirs in would necessarily be costly; it would which the waters may be for a time re- perhaps amount to as much as ten milltained during the period of floods. ion dollars a year.

It seems, however, Some years ago a distinguished en- possible that for this cost we might obgineer, Mr. Charles Ellet, suggested a tain a substantial immunity from the system of controlling the floods of the worst destruction accomplished by our Mississippi Valley. He proposed to floods. Even if this system should be build certain dams in the upper waters adopted, it would be necessary, decade of the Mississippi system, in which, dur- by decade, as the process of forest reing the times of food, a considerable moval advanced, to extend still further part of the flow might be impounded, to the area of the storage reservoirs. be discharged into the channels at such While the proper control of the Mistimes as was needed to maintain a nav- sissippi drainage system is of great imigable depth of water. There are cer- portance to the nation at large; to the tain objections to the details of the sys- States which border upon its waters it is tem proposed by Mr. Ellet, the principal a matter of vital necessity. Whether of which is that the existence of very this great task is to be undertaken large reservoirs would add another by the Federal Government or by assource of danger to those which the sociated Commonwealths, there can be floods now inflict upon the valleys of no question that it should be at once these streams. It is difficult to build entered upon. Every year increases the retaining dams so that they may be ab- magnitude of the necessities and the solutely secure from the risks of giving difficulty of devising means to meet way. The bursting of such a dam in them. time of flood might prove peculiarly dis Although the American theory of govastrous.

ernment looks to the initiative of the inIt seems, however, possible that a slight dividual for the most of the acts which modification of Mr. Ellet's plan would in other lands are accomplished by the more effectively accomplish the end he state, it still has to confess that certain had in view, without creating the risks classes of work are only accomplishable above noted. For in place of half a by federal control. Our great river is dozen great artificial lakes, we should fast becoming a common enemy of our adopt the plan of having many thousands, people ; it is our duty to restrain its or tens of thousands, of smaller reservoirs, ravages as we would those of any other 80 arranged that no one would, by its foe of the state.


By Octave Thanet.

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UNT BETSEY sunburned white hair and his big, mel-
GRAHAM, who kept ancholy, blue eyes.
the plantation tav “ An' so ”-Aunt Betsey was pursuing
ern, stood in her a conversation already begun—" so you
wide gallery - way, paw's dead, but you Uncle Bruno, he
waiting for the mill holps ye all ?”
whistle to send her "I guess we'd be in the poor house,
boarders to supper.

if he didn't,” said Otto. “He got me There was not a kinder woman in Law- this chance. Mr. Bassett's a Knight, rence County, or, in a homely fashion, a like my uncle.” better cook.

“ A witch ?” Look at her, now, in the shadow of "A Knight of Labor, you know." the old-fashioned porch, built when “Never heerd on 'em,” said Aunt bears were shot in the cypress brake ; Betsey placidly. her portly form is clad in a red and Otto straightened himself, his eyes black striped cotton gown and white flashing and his narrow chest swelling. apron; her gray hair is thick like a You aint !” he cried ; “why they're girl's, her little brown eyes twinkle jest the grandest order ever was! They're jovially, the hardy late roses bloom on going to make all the bad rich people her tanned cheeks, and nobody on the quit oppressing the poor and make all plantation has such beautiful, white diffrent lawsstore teeth.

Oh, sorter like the Ku-Klux ?” She sees the road, a broad, then a “Oh no, mum, not a bit like the Kunarrow, then a fading streak of yellow, Klux. They are all good men and they cutting the cotton-fields and defining shall make all the poor people own their the borders of the brake. Some of the own property and Uncle Bruno kin come houses which she sees are trig and home at four o'clockpainted; some have crooked, dark roofs, "Sekrit soci'ty, hey?" and chimneys bulging sidewise against They've got to be, mum ; 'cause else black-gray walls. It is the old South them bloated capitalists would find out and the new. Looking obliquely to the all their plans.” right, she sees the smithy under its great “That 'ar sounds powerful like Ku“ water oaks,” and, almost at right Klux,” said Aunt Betsey critically. “They angles, the carpenter shop and the gaunt all was mighty biggity, but I never seen black shape of the old mill. Further nuthin' come er thar braggs 'cept folkses down the river bank is the new mill, ketchin' cole, romancin' roun' nights, by which has men crawling over its roof the dark of the moon. I know all 'beout and rings with the click of hammers. them sekrit soci'ties. I read a book 'beout

But soon Aunt Betsey's eyes returned 'em, oncet. Thar was a man taken a to Otto Knipple, splitting wood just in oath on a skull wilst two men hilt dadfront of the porch. She thought, sor- gers over him iz was dreepin' with jore. rowfully, that he would never make out Warn't that orful?” with that hickory ; but what could you “Yes, mum, please go on!” cried Otto, expect of a boy raised in St. Louis and revelling in the lurid picture. come down to the Black River with “By the fitful glem er a dyin' lamp,” those ornery, trifling St. Louis car. Aunt Betsey continued. "Must of ben one penters?

er them grease lamps, they're allers devilOtto was a scrap of a lad, carrying a in' someway. I disremember jes whut premature age in his sallow, care-worn, 'twas he swore, but I know his ha'r, iz eager little features, that were the sal- was black like the ravin’s wing, turned lower and more eager for his mat of plum w'ite in a single night. His folks

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