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of still water they encounter, and thus reduce the storage capacity of the reservoirs into which they flow. Mill dams completely filled with sediment are to be seen everywhere, and offer good demonstrations of the damage to storage reservoirs from silting.

The regulation of streams by storage reservoirs is really an imitation of what nature is able to accomplish by the forests. Forests at the sources of the streams are veritable storage reservoirs, and without them no artificial remedy can be either adequate or permanent. Erosion destroys reservoirs, and must be controlled if reservoirs are to succeed. This can be done only by conserving or restoring the forests. The forest cover alone can reduce the amount of sediment carried by water, and make possible the permanent improvement of inland waterways. To check erosion by reforestation, work must begin in the highlands, because there the slopes are steepest, the rainfall greatest, and the action of frost most considerable, and therefore the process of erosion is most rapid and the results most destructive.

No one will deny the necessity for engineering methods to cope with the moderate deposits of silt and the seasonal irregularities in flow, which may indeed be lessened by forest cover, but which are unavoidable so long as the sun shines and the rain falls. Yet it remains true that a forest cover interposed between rain and rock affords the best natural means for regulating streams and reducing the loads of detritus. Without such a forest cover every attempt to improve the regimen and the channel of a stream will be little more than a temporary expedient.

Both wide experience and scientific investigation have shown that there are two functions exercised by the forest in relation to stream-flow.

I. Its tendency to reduce the difference between high and low water, an influence which is of most importance in the distribution of flood crests, and in maintaining a steady flow of water during the

different seasons of the year and during cycles of dry and wet years.

2. Its value as a surface protection against soil erosion, thus reducing the solid burden of storm waters, and decreasing the deposits of sand and silt, which are the causes of shallow and changing channels.

These two functions follow from the very nature of the forest as a soil cover. The roots of trees penetrate through the soil to the underlying rock, where they fix themselves in the crevices, in this way hold in place the loose soil and prevent slipping and washing. The crowns of the trees break the force of the rain and also protect the soil from being carried away to the lower valleys during heavy storms. The leaves and the branches allow the rain to reach the ground but gradually; after a rain, water continues to drip from the crown for several hours, and the soil is thus enabled to absorb the greater part of it. Screened from the rays of the sun and covered with a surface mulch of fallen leaves and humus, the soil remains loose and granular in structure and is therefore capable of imbibing and retaining water with sponge-like capacity. It is strewn with fallen leaves, branches, and trunks, and traversed by a net-work of dead and live roots which impede the superficial runoff of water after heavy storm. This retardation of the superficial run-off allows more of it to sink into the ground through the many channels left in the soil by decayed roots. Surface run-off of rain water is wasteful and destructive, and unless artificially controlled serves as a rule no useful purpose and may inflict great loss. Sub-surface drainage makes the best use of the total precipitation that reaches the ground. It serves both for the sustenance of plant life and for the flow of streams. Accordingly the agency of the forest cover in increasing the seepage run-off at the expense of the surface run-off is the most important function which the forest performs in relation to water supply.

A common conception of the effect of

forest destruction upon climate is that it reduces the amount of rainfall. Because springs become dry and streams shrink in a deforested region, it is assumed that less rain must fall. Whether or not there be any truth in this assumption (I believe there is), it is certain that the main cause of the observed facts is the profound effect which forest destruction has upon the course which the water takes after it reaches the ground. The greatest influence of the forest is not upon the amount of rain which falls, but on what becomes of the rain after it falls. The water that sinks into the ground passes for greatly varying distances beneath the surface before reappearing, and is thus drawn off gradually from the forested watershed and supplies the brooks with pure water relatively free from detritus.

How active a part is played by the forest in regulating the run-off is clearly shown by actual measurements of the flow of streams which drain forested and unforested watersheds. A typical illustration of streams from barren, treeless watersheds may be found in the flow of Queen Creek, in Arizona. This stream discharges only in violent freshets, recurring usually as great floodwaves which subside almost as soon as they arise. The area of the drainage basin is 143 square miles, of which 61 per cent. is above an elevation of 3,000 feet. The rainfall is estimated to be about 15 inches. The maximum flood discharge of Queen Creek in 1896 was 9,000 cubic feet per second, and the mean discharge was 15 cubic feet per second; during a large portion of the year the stream was entirely dry.

Cedar Creek, in Washington, is typical of streams flowing from timbered watersheds. The basin of Cedar Creek lies on the western slope of the Cascade Mountains and is covered with a dense forest and a very heavy undergrowth of ferns and moss. The drainage area is the same as that of Queen Creek, 143 square miles. The precipitation for the year 1897 was about 93 inches for the lower portion of the basin, and probably 150 inches on the mountain summits; in spite, however, of

the fact that the precipitation in Cedar Creek basin was from six to nine times more than that in Queen Creek basin, the maximum flood discharge of Cedar Creek for 1897 was but 3,601 cubic feet per second, as against the 9,000 cubic feet of Queen Creek. On the other hand the flow of Cedar Creek was continuous throughout the year, and the minimum discharge was never less than 27 per cent. of the mean of the year. The mean discharge of Cedar Creek was 1,089 cubic feet as against 15 feet for Queen Creek. This radical difference in the behavior of the two streams can be explained only by the difference in the soil cover of the two basins. Cedar Creek basin is covered with a heavy forest, while Queen Creek basin is almost entirely bare, with but a few scattering pinion trees and a little brush or grass.

Mr. Marsden Manson, in discussing the stream flow from certain points on the Yuba River basin, California, makes a very interesting comparison between its two branches, North Fork and South Fork, of which the first has a forested and the second a denuded basin. Both of the catchment areas lie on the western slope of the Sierra Nevada, and have exposures of marked similarity.

The south branch of the North Fork has a watershed area of 139 square miles, which gave in 1900 a maximum run-off of 113 cubic feet per second, or 0.8 cubic feet per second per square mile. This drainage area is well covered with timber and brush, and for four months gives a minimum run-off of 1,441,125,000 cubic feet.

On the South Fork, above Lake Spaulding, there is a watershed of 120 square miles from which the scattering timber that once existed has been cut off. The run-off of this area is practically nothing for four months in each year, because of this absence of forests. If this area was afforested, and gave a minimum run-off of 0.8 cubic foot per second per square mile, the discharge would be 100 cubic feet per second, or equivalent to 1,036,800,00 cubic feet of effective stor

age capacity. To supply water for mining and power purposes a number of costly storage reservoirs have been built on the South Fork. By reforesting the small watershed a natural reservoir would be created whose storage capacity would be almost equal to the storage capacity of all the reservoirs above Lake Spaulding dam.

A careful study of the behavior of the streamflow on several small timbered and non-timbered catchment areas in the San Bernardino Mountains of Southern California, made by Professor Toumey for the Forest Service in 1902, brought out in a most convincing manner the effect of the forest in decreasing surface run-off and sustaining the flow of mountain streams. Three timbered drainage areas were studied. These gave during December-a month of unusually heavy precipitation-a run-off of but 5 per cent. of the heavy rainfall for that month; during the following months of January, February and March, they gave a run-off of approximately 37 per cent. of the total precipitation, and three months after the close of the rainy season still supported a well-sustained streamflow. At the same time, the similar and neighboring nontimbered catchment area under observation gave during December a run-off of 40 per cent. of the rainfall, and during the three following months a run-off of 95 per cent. In April the run-off was less than one-third of that from each of the forest catchment areas, and in June the stream from the non-forested area was dry.

Streams flowing from barren, treeless watersheds carry an amount of gravel, sand and soil which is simply enormous compared to the amount in streams from timbered areas. Thus the United States Geological Survey determined the amount of silt carried by the Gila River at the Buttes, a stream whose basin and regimen is similar to that of Queen Creek, of Arizona, to be 10 per cent. of the volume wet or 2 per cent. of solids. To appreciate these figures it must be remembered that one-fourth of one per cent. of solid

burden in the stream is enough to make the water turbid.

As long as the ground is protected by a natural covering of forest growth, rainfall has very little erosive action. It is only after the ground is laid bare by the removal of the forest that the erosion of the soil attains dangerous proportions.

There has, of course, always been, even when the natural forests were unimpaired, some erosion, especially in the watersheds of streams in the Southeast and Southwest, but not to the extent which now obtains, and the present erosion is not only excessive, but is yearly increasing. It is the price, and in a large measure the product, of necessary agricultural and industrial development under defective methods of work. According to studies of Humphreys and Abbott the wearing down of the earth's surface over a region such as the Mississippi Valley is something like one foot in five thousand years, independent of human action. At such a rate of erosion the amount of sediment carried by the Mississippi River before the dawn of civilization could not be more than 70,000,000 tons per year. According to Professor Shaler the wearing down of the Mississippi Valley under complete tillage will be about the same as that of the Valley of the Po in northern Italy, or one foot in one thousand years. such a rate of erosion, the solid burden of the Mississippi River should be 350,000,000 tons. But the amount of solid matter carried every year by the Mississippi River was estimated several years ago to be 400,000,000 tons. In other words, the erosion had then reached, if not exceeded, that of the Po Valley. It is greater now. The formation of soil through underground decay of the rocks cannot keep pace with such a rate of erosion. Unless measures are taken to check it the fertile layer of soil must gradually disappear, as has happened already over large areas in the Old World from precisely similar

causes.

At

The ruinous effects of the destruction of mountain forests upon the navigability of streams and the cultural results of

human labor have long been felt by most European countries and attempts have been made to remedy them. France in particular has learned by bitter experience how terrible the lowlands suffer when the mountains lose their forest cover, and has now proved by practical demonstrations that the losses produced by forest destruction can be repaired only by reforestation.

ing about 425,000 acres of land, 58 per cent. of which belonged to the government, 25 per cent. to communities and 17 per cent. to private individuals. France has now a far-reaching plan for bringing under control about 3,000 torrential streams in the Alps, Pyrenees, Ardennes, Cevennes and the central plateaus, at a cost of $40,000,000. Of this 35 per cent., or $14,000,000, is for reforestation alone.

In Austria, attention was attracted to reforestation of watersheds as a means of regulating stream flow by the great floods in the Tyrol and Kärnton. Austrian foresters enumerate over 500 torrents in the Tyrol, whose basins need reforesting, and on 100 streams the work has already begun. Similar work is being extensively carried on elsewhere among the Austrian mountains.

In Italy the pressing need of reforesting land in the Apennines and the southern slopes of the Alps has long been urged upon the government by the people on account of the immense destruction wrought annually by the Po, which is now three times as destructive to land as it was in the past century. As a result of numerous petitions, a bill was passed in 1882, whereby waste land amounting to nearly a million acres was to be gradually reforested, involving an initial cost of $8.40 per acre beside current expenses.

During the French revolution of 1789 extensive clearings were made in the forests of the Provençal Alps. The French Government early recognized the danger which bare areas threatened to property and industry, and emphasized the importance of reforestation. In 1842 the classical investigations by Surell made it evident that forest clearing was responsible for most of the damage caused by mountain torrents, and that in reforestation lay the remedy. Laws were enacted in 1860 and 1864 which recognized that reforestation, to improve streamflow, to restore the soil, and to regulate torrents was of public utility, and therefore that it was the duty of the government. Two methods were adopted to carry out the work. Government assistance for reforestation voluntarily undertaken by communities or private individuals; and compulsory reforestation by means of temporary dispossession, whereby the option was left with the owner of recovering his lands, either by reimbursement of cost or by surrendering one-half the area to the government. The work was entrusted to the French Forest Service, and from 1861 to 1877, inclusive, an area of 233,590 acres of mountain land was put into forest or grass at a cost, including certain incidental expenses, of $2,900,ooo. At the close of the last century the fund appropriated by the French Gov- Forests at high altitudes, at the sources ernment for protective protective afforestation of navigable streams, on shifting sands, on amounted to $12,500,000 in round num- banks of large rivers, and on steep, exbers, of which $4,900,000 went toward posed slopes are recognized in most of purchase of land and $7,600,000 was spent the European countries as "protective forin improvement of streams and reforesta- ests," and are managed with the prime tion of their drainage basins. The work object of preventing washing and erosion resulted in bringing under control a num- of soil. Thus at high altitudes on steep, ber of torrential streams and in reforest-exposed slopes and near the timber line,

The great efforts of nearly all the states of Europe to counteract the effects of indiscriminate forest clearing, efforts which involve an outlay of scores of millions of dollars, show how important the mountain forests are. They should be regarded as a sort of capital, whose function in the national economy is far higher than the income which the timber may yield.

clear cutting as a rule is forbidden and timber must always be cut either in narrow strips or by gradual thinning. Severe governmental regulations controlling the management of protective forests on

private lands are common in Europe. There can be little doubt that similar action will be forced upon us in the United States by the results of destroying our mountain forests.

WHY A CLASSIC IS A CLASSIC1
ARNOLD BENNETT

Arnold Bennett (1867- ) is a business man of letters. His keen eyes run over the literary public, appraise their wants, and fill them. Consequently he writes popular philosophical essays (How to Live on Twenty-four Hours a Day) and popular fiction (The Pretty Lady), as well as fiction of genuine literary power, such as the Clayhanger trilogy and the Old Wives' Tale, which so largely influenced contemporary novelists. But, despite his ability to give the public what it wants, Mr. Bennett tells us in The Truth About an Author that he has never written down to the public taste in any work of any length, and he has always held Beauty before him as his object. "Why a Classic Is a Classic" (1909), from Literary Taste, How to Form It, a series of essays on literature, shows Mr. Bennett at his best in freeing a time-worn subject from cant phrases and wearisome formality.

THE large majority of our fellowcitizens care as much about literature as they care about aëroplanes or the programme of the Legislature. They do not ignore it; they are not quite indifferent to it.

But their interest in it is faint and perfunctory; or, if their interest happens to be violent, it is spasmodic. Ask the two hundred thousand persons whose enthusiasm made the vogue of a popular novel ten years ago what they think of that novel now, and you will gather that they have utterly forgotten it, and that they would no more dream of reading it again than of reading Bishop Stubb's Select Charters. Probably if they did read it again they would not enjoy it not because the said novel is a whit worse now than it was ten years ago; not because their taste has improved-but because they have not had sufficient practice to be able to rely on their taste as a means of permanent pleasure. They simply don't know from one day to the next what will please them.

In the face of this one may ask: Why does the great and universal fame of classical authors continue? The answer

1From Literary Taste, How to Form It by Arnold Bennett. George H. Doran Company, Publishers. Reprinted by permission.

is that the fame of classical authors is entirely independent of the majority. Do you suppose that if the fame of Shakespeare depended on the man in the street it would survive a fortnight? The fame of classical authors is originally made, and it is maintained, by a passionate few. Even when a first-class author has enjoyed immense success during his lifetime, the majority have never appreciated him so sincerely as they have appreciated second-rate men. He has always been reinforced by the ardor of the passionate few. And in the case of an author who has emerged into glory after his death, the happy sequel has been due solely to the obstinate perseverance of the few. They could not leave him alone; they would not. They kept on savoring him, and talking about him, and buying him, and they generally behaved with such eager zeal, and they were so authoritative and sure of themselves, that at last the majority grew accustomed to the sound of his name and placidly agreed to the proposition that he was a genius; the majority really did not care very much either way.

And it is by the passionate few that the renown of genius is kept alive from one generation to another. These few are always at work. They are always rediscovering genius. Their curiosity and

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