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by help of which he can collect together “apocalyptic,” to describe something at in a few moments all the texts upon any once very terrible and very grand. particular subject, such as the sea, the Whether one understands the meaning of wind, the sky, human life, the shadows of this mysterious text makes very little difevening. The study of the Bible is not ference; the sonority and the beauty of one which I should recommend to very its sentences, together with the tremenyoung Japanese students, because of the dous character of its imagery, can not but quaintness of the English. Before a powerfully influence mind and ear, and good knowledge of English forms is ob- thus stimulate literary taste. At least tained, the archaisms are apt to affect the two of the great prose writers of the ninestudents' mode of expression. But for teenth century, Carlyle and Ruskin, have the advanced student of literature, I been vividly influenced by the book of the should say that some knowledge of the Revelation. Every period of English finest books in the Bible is simply indis- literature shows some influence of Bible pensable. The important books to read study, even from the old Anglo-Saxon are not many. But one should read at days; and during the present year, the least the books of Genesis, Exodus, Ruth, study has so little slackened that one conEsther, the Song of Songs, Proverbs stantly sees announcements of new works and, above all, Job. Job is certainly the upon the literary elements of the Bible. grandest book in the Bible; but all of Perhaps one of the best is Professor those which I have named are books that Moulton's “Modern Reader's Bible,” in have inspired poets and writers in all de- which the literary side of the subject repartments of English literature to such an ceives better consideration than in any extent that you can scarcely read a mas- other work of the kind published for genterpiece in which there is not some conscious or unconscious reference to them. If this brief lecture has shown the real Another book of philosophical importance place of the King James version in Engis Ecclesiastes, where, in addition to much lish literature, and suggested to you the proverbial wisdom, you will find some reason why the book has an all-important admirable world-poetry-that is, poetry value, independently of any religious which contains universal truth about thought in it-quite sufficient has been human life in all times and all ages. Of said. It would be of no use whatever to the historical books and the law books I spend the time otherwise utilizable, in do not think that it is important to read pointing out beauties of the text. What much; the literary element in these is not beauty there is is of a kind so simple that so pronounced. It is otherwise with the explanation is quite unnecessary. Where prophetic books, but here in order to ob- I think that the value of the reading tain a few jewels of expression, you have would be greatest for you, is in regard to read a great deal that is of little value. to measure and symmetry and euphony Of the New Testament there is very lit- in English construction. But that means tle equal to the old in literary value; in- a great deal—so much that the best illusdeed, I should recommend the reading tration of it is the observation already only of the closing book-the book called made, that all English written since the the Revelation, or the Apocalypse, from sixteenth century has been colored by the which we have derived a literary adjective | Bible.
THE RELATION OF FORESTS TO STREAM CONTROL
GIFFORD PINCHOT Gifford Pinchot (1865- ) was the first man to do systematic work in forestry in the United States. For twelve years he was connected with the national government as chief of the Bureau of Forestry, and labored diligently for the conservation of our national resources. As a result of political differences with his superior, Secretary Ballinger of the Interior, he was dismissed from office in 1910, and soon became instrumental in the formation of the Progressive Party. Since 1903 he has been a professor at Yale, and since 1910, the president of the National Conservation Association. The following article, published in 1908, is an example of straightforward scientific exposition.
The phenomenal development of in- courses of many of our rivers, but it candustry and the consequent increased de- not and does not claim to regulate in the mand for transportation have turned at- least the water supply of the streams. tention to our most natural means of in- The method of storage reservoirs, exland transportation—the lakes and riv- tensively tried in France, has been sug
It has forced us to realize that our gested as a method of river improvement streams, in spite of the tens of millions of in the United States. Reservoirs filled dollars appropriated for their develop in the spring freshet season serve to inment, are becoming less navigable. In- crease the flow later in the year when the creasing amounts of sediment are de- streams run low. Floods may thus be posited each year in their middle and prevented, and the immense loads of silt lower courses, while the flow of the which they would otherwise have brought streams themselves becomes less regular. | down are thus kept from being dropped Navigable with difficulty, if at all, dur- | by the slow current in the lower chaning the summer, they become turbulent nel. Theoretically this method of storand turbid during the spring, overflow age reservoirs will accomplish all that their banks, and often carry destruction to can be desired in regulating stream flow life and property.
The skill of our en- and preventing excessive deposition, if gineers is taxed to the utmost to keep har- only adequate storage capacity is availabors and rivers free from the constantly ble. In practice, too, it will doubtless recurring deposits of sediment. Because be efficient in places where the erosion is of the rapidly increasing tonnage and not rapid. But the great disadvantage draft of vessels, it is not sufficient merely of this method, as is proved by the exto maintain the present depth of our riv- perience of the French engineers, lies in ers and harbors. Their depth must be the fact that the reservoirs themselves beconstantly increased or they will gradu- come clogged with detritus and must ally fail to accommodate the larger ves- sooner or later, varying with the forest sels, and such of them as fail must conditions and the character of the topogfinally be abandoned altogether.
raphy drained, be either abandoned or More powerful dredging machinery is maintained by constant clearing out at constantly coming into use. Efforts are large expense. common to prevent the deposit of sedi- The engineers of the United States ment by confining streams to channels Reclamation Service fully realize that the narrow enough to accelerate the current amount of solid matter carried by a and so lessen the rate of deposition. This stream is a very serious problem in conmethod of channel adjustment has ac- nection with the construction of storage complished great good in improving the reservoirs for irrigation purposes. Streams
from barren watersheds abound in violent Reprinted by permission from The Annals of the American Academy of Political
freshets which carry with them eroded and Social Science, January, 1908, Vol. XXXI, sediment, to be deposited in the first pool
of still water they encounter, and thus re- different seasons of the year and during duce the storage capacity of the reser- cycles of dry and wet years. voirs into which they flow. Mill dams 2. Its value as a surface protection completely filled with sediment are to be against soil erosion, thus reducing the seen everywhere, and offer good demon- solid burden of storm waters, and decreasstrations of the damage to storage reser- ing the deposits of sand and silt, which voirs from silting.
are the causes of shallow and changing The regulation of streams by storage channels. reservoirs is really an imitation of what These two functions follow from the nature is able to accomplish by the for- very nature of the forest as a soil cover. ests. Forests at the sources of the The roots of trees penetrate through the streams are veritable storage reservoirs, soil to the underlying rock, where they and without them no artificial remedy can fix themselves in the crevices, in this be either adequate or permanent.
way hold in place the loose soil and sion destroys reservoirs, and must be con- prevent slipping and washing. The trolled if reservoirs are to succeed. This crowns of the trees break the force of the can be done only by conserving or restor- rain and also protect the soil from being ing the forests. The forest cover alone carried away to the lower valleys during can reduce the amount of sediment carried heavy storms. The leaves and the by water, and make possible the perma- branches allow the rain to reach the nent improvement of inland waterways. ground but gradually; after a rain, water To check erosion by reforestation, work continues to drip from the crown for must begin in the highlands, because there several hours, and the soil is thus enabled the slopes are steepest, the rainfall great- to absorb the greater part of it. Screened est, and the action of frost most consid- from the rays of the sun and covered with erable, and therefore the process of ero- a surface mulch of fallen leaves and husion is most rapid and the results most mus, the soil remains loose and granudestructive.
lar in structure and is therefore capable No one will deny the necessity for of imbibing and retaining water with engineering methods to cope with the sponge-like capacity. It is strewn with moderate deposits of silt and the sea- fallen leaves, branches, and trunks, and sonal irregularities in flow, which may in- traversed by a net-work of dead and live deed be lessened by forest cover, but roots which impede the superficial runwhich are unavoidable so long as the sun off of water after heavy storm. This shines and the rain falls. Yet it remains retardation of the superficial run-off altrue that a forest cover interposed be- | lows more of it to sink into the ground tween rain and rock affords the best through the many channels left in the soil natural means for regulating streams and by decayed roots. Surface run-off of reducing the loads of detritus. Without rain water is wasteful and destructive, such a forest cover every attempt to im- and unless artificially controlled serves as prove the regimen and the channel of a a rule no useful purpose and may inflict stream will be little more than a tempo- great loss. Sub-surface drainage makes rary expedient.
the best use of the total precipitation that Both wide experience and scientific in- reaches the ground. It serves both for vestigation have shown that there are two the sustenance of plant life and for the functions exercised by the forest in rela- flow of streams. Accordingly the agency tion to stream-flow.
of the forest cover in increasing the seep1. Its tendency to reduce the difference age run-off at the expense of the surface between high and low water, an influ- run-off is the most important function ence which is of most importance in the which the forest performs in relation to distribution of flood crests, and in main- water supply. taining a steady flow of water during the A common conception of the effect of forest destruction upon climate is that it the fact that the precipitation in Cedar reduces the amount of rainfall. Because Creek basin was from six to nine times springs become dry and streams shrink in more than that in Queen Creek basin, the a deforested region, it is assumed that less maximum flood discharge of Cedar Creek rain must fall. Whether or not there for 1897 was but 3,601 cubic feet per be any truth in this assumption (I believe second, as against the 9,000 cubic feet of there is), it is certain that the main cause Queen Creek. On the other hand the of the observed facts is the profound ef- flow of Cedar Creek was continuous fect which forest destruction has upon throughout the year, and the minimum the course which the water takes after it discharge was never less than 27 per cent. reaches the ground. The greatest influ- of the mean of the year. The mean disence of the forest is not upon the amount charge of Cedar Creek was 1,089 cubic of rain which falls, but on what becomes feet as against 15 feet for Queen Creek. of the rain after it falls. The water This radical difference in the behavior that sinks into the ground passes for of the two streams can be explained only greatly varying distances beneath the sur- by the difference in the soil cover of the face before reappearing, and is thus two basins. Cedar Creek basin is covdrawn off gradually from the forested ered with a heavy forest, while Queen watershed and supplies the brooks with Creek basin is almost entirely bare, with pure water relatively free from detritus. but a few scattering pinion trees and a How active a part is played by the for
little brush or grass. est in regulating the run-off is clearly Mr. Marsden Manson, in discussing shown by actual measurements of the flow the stream flow from certain points on of streams which drain forested and un- the Yuba River basin, California, makes forested watersheds. A typical illustra- a very interesting comparison between its tion of streams from barren, treeless two branches, North Fork and South watersheds may be found in the flow of Fork, of which the first has a forested Queen Creek, in Arizona. This stream and the second a denuded basin. Both of discharges only in violent freshets, re- the catchment areas lie on the western curring usually as great floodwaves which slope of the Sierra Nevada, and have exsubside almost as soon as they arise. The posures of marked similarity. area of the drainage basin is 143 square The south branch of the North Fork miles, of which 61 per cent. is above an has a watershed area of 139 square miles, elevation of 3,000 feet. The rainfall is which gave in 1900 a maximum run-off estimated to be about 15 inches. The of 113 cubic feet per second, or 0.8 cubic maximum flood discharge of Queen Creek feet per second per square mile. This in 1896 was 9,000 cubic feet per second, drainage area is well covered with timber and the mean discharge was 15 cubic feet and brush, and for four months gives a per second ; during a large portion of the minimum run-off of 1,441,125,000 cubic year the stream was entirely dry.
Cedar Creek, in Washington, is typical On the South Fork, above Lake of streams flowing from timbered water- Spaulding, there is a watershed of 120 sheds. The basin of Cedar Creek lies on square miles from which the scattering the western slope of the Cascade Moun- timber that once existed has been cut off. tains and is covered with a dense forest The run-off of this area is practically and a very heavy undergrowth of ferns nothing for four months in each year, beand moss.
The drainage area is the same cause of this absence of forests. If this as that of Queen Creek, 143 square miles. area was afforested, and gave a minimum The precipitation for the year 1897 was run-off of 0.8 cubic foot per second per about 93 inches for the lower portion of square mile, the discharge would be 100 the basin, and probably 150 inches on the cubic feet per second, or equivalent to mountain summits; in spite, however, of 1,036,800,00 cubic feet of effective stor
age capacity. To supply water for min- burden in the stream is enough to make ing and power purposes a number of the water turbid. costly storage reservoirs have been built on As long as the ground is protected by the South Fork. By reforesting the small a natural covering of forest growth, rainwatershed a natural reservoir would be fall has very little erosive action. It is created whose storage capacity would only after the ground is laid bare by the be almost equal to the storage capacity removal of the forest that the erosion of of all the reservoirs above Lake Spaulding the soil attains dangerous proportions. dam.
There has, of course, always been, even A careful study of the behavior of the when the natural forests were unimpaired, streamflow on several small timbered and some erosion, especially in the watersheds non-timbered catchment areas in the San of streams in the Southeast and SouthBernardino Mountains of Southern Cali- west, but not to the extent which now fornia, made by Professor Toumey for obtains, and the present erosion is not the Forest Service in 1902, brought out only excessive, but is yearly increasing. in a most convincing manner the effect of It is the price, and in a large measure the the forest in decreasing surface run-off product, of necessary agricultural and inand sustaining the low of mountain dustrial development under defective streams. Three timbered drainage areas methods of work. According to studies were studied. These gave during De- of Humphreys and Abbott the wearing cember-a month of unusually heavy pre
down of the earth's surface over a region cipitation-a run-off of but 5 per cent. of such as the Mississippi Valley is somethe heavy rainfall for that month; during thing like one foot in five thousand years, the following months of January, Febru- independent of human action. At such ary and March, they gave a run-off of a rate of erosion the amount of sediment approximately 37 per cent. of the total carried by the Mississippi River before precipitation, and three months after the the dawn of civilization could not be more close of the rainy season still supported a than 70,000,000 tons per year. Accordwell-sustained streamflow. At the same ing to Professor Shaler the wearing down time, the similar and neighboring non- of the Mississippi Valley under complete timbered catchment area under observa- tillage will be about the same as that of tion gave during December a run-off of the Valley of the Po in northern Italy, 40 per cent. of the rainfall, and during or one foot in one thousand years. At the three following months a run-off of such a rate of erosion, the solid burden of 95 per cent. In April the run-off was the Mississippi River should be 350,000,less than one-third of that from each of 000 tons. But the amount of solid matter the forest catchment areas, and in June carried every year by the Mississippi the stream from the non-forested area was River was estimated several years ago to dry.
be 400,000,000 tons. In other words, the Streams flowing from barren, treeless erosion had then reached, if not exceeded, watersheds carry an amount of gravel, that of the Po Valley. It is greater now. sand and soil which is simply enormous The formation of soil through undercompared to the amount in streams from ground decay of the rocks cannot keep timbered areas. Thus the United States pace with such a rate of erosion. Unless Geological Survey determined the amount measures are taken to check it the fertile of silt carried by the Gila River at the layer of soil must gradually disappear, as Buttes, a stream whose basin and regimen has happened already over large areas in is similar to that of Queen Creek, of the Old World from precisely similar Arizona, to be 10 per cent. of the volume causes. wet or 2 per cent. of solids. To appre- The ruinous effects of the destruction ciate these figures it must be remembered of mountain forests upon the navigability that one-fourth of one per cent. of solid of streams and the cultural results of