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render. Many he must leave where they are lest under new surroundings they change their habits.

...

The stronger winged grasshoppers were able to fly "hundreds of miles from the Rocky Mountains to the Mississippi Valley, alighting first where cultivated lands begin. Thus Kansas, Nebraska and the Dakotas were preëminently sufferers from grasshopper invasions, and not infrequently conditions were sufficiently good there to permit the insects to lay their eggs, providing for a brood which the year following destroyed the vegetation while still unfledged, and then migrated yet further east to do destructive work as adults and to perish gradually, in the egg stage, in the moist unsuitable soil. No one who has not seen grasshoppers in this Western country can form any real idea of their actual abundance, and their destructiveness has been the theme of many a writer. Conditions now are much better than they were and can never again be quite as bad. A large area of what was at one time ideal breeding ground, is now irrigated and under cultivation, and the enormous belt of alfalfa and other crops now basing the foothills, checks and takes up the migrating hordes that occasionally start from the uncultivated areas. The march of advancing civilization spells the doom of some of these grasshopper species, as it has that of many another animal." 31

...

The Department of Agriculture has recently published a bulletin based on the reports of some two hundred observers in the district east of Kansas and north of North Carolina. There were found for each 100 robins about 83 English sparrows, 49 catbirds, 37 brown-thrashers, 28 house-wrens, 27 kingbirds, and 26 bluebirds.

31 SMITH, J. В. о. с., р. 56.

"The census covered 58 of the 108 acres of the average farm of the Northeastern States and revealed on this area a bird population of 69 nesting pairs, and on the remaining 50 acres it is estimated that there would be about one pair to the acre; in all, 114 nesting pairs to the 108 acres of farmed land. On the 46 acres of wild land existing for each 108 acres of farmed land it is safe to assume that there would be fewer birds than on the census covered area." Heavy forests contain relatively few birds. The only large census returned showed in an Idaho forest 254 pairs of breeding birds on 768 acres.

The densest bird population was in the town of Chevy Chase, Maryland, in which the houses are surrounded by large yards containing many trees. Thirty-four different species were found nesting on the twenty-three acres examined, with a total of 148 pairs of native birds and thirteen pairs of English sparrows.

...

"An approximate average of one pair of birds to each acre of farm land was found, but individual censuses show that it is possible, under strictly farm conditions, very largely to increase this number. Near Wellington, Va., a tract of 49 acres of a dairy farm, of rather less than the average of plowed land, supported a bird population of 137 pairs, or 3 pairs to the acre. Near Albany, Mo., 80 acres was divided into 14 acres of plowed land, 27 acres of hayfields, a brushy pasture, with a little heavy timber along the banks of a small stream, and the customary farmyard, orchard, garden, etc. The conditions for bird life were probably more favorable than the average, but not sufficiently different to account for the 298 pairs of birds nesting on the tract."

"On a 50 acre tract at Viresca, Va., where the birds have been strictly protected during the last seven years, exact censuses show a 50 per cent increase in the birds during the last four years." 32

After twenty-five years of agitation the government of the United States began in 1913 the control of all migratory birds, its law supplanting all state laws, determining the conditions under which they may be killed and sold. The importation of egret plumes, etc., has been prohibited. Mrs. Sage has given Marsh Island in the Gulf of Mexico to the government as a bird refuge. The success here has stimulated similar movements in Europe. Game preserves are being established by both state and national governments as well as by private citizens. It is not too much to hope that we are entering a new era in our relations to nature. The control to be discussed in the next chapter is the direction of nature's forces to produce the maximum of good to ourselves not the reckless and shortsighted display of mere brute force and the destruction of the very basis of our life.

SUGGESTIONS FOR READING

BRAUN, MAX. Animal Parasites of Man. 1906.

DARWIN, CHARLES. The Formation of Vegetable Mould Through

the Action of Worms. 1881.

DRUMMOND, H. The Ascent of Man. 1894.

FABRE, J. H. Social Life in the Insect World. 1912.

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Hawks and Owls of the United States. 1893.
Useful Birds and Their Protection. 1907.
Game Birds, Wild Fowl and Shore Birds. 1913.
Biological Aspects of Human Problems. 1911.

HORNADAY, W. T. Our Vanishing Wild Life. 1912.

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Wild Life Conservation in Theory and Practice. 1914.

KROPOTKIN, P.
LIPMAN, J. G.
32 Bulletin, United States Department of Agriculture, No. 187.

Mutual Aid. 1902.
Bacteria in Relation to Country Life. 1908.

MERRIAM, C. H. The English Sparrow in America. 1889.
PAMMEL, J. H. Weeds of the Farm and Garden. 1911.
SHELFORD, V. E. Animal Communities in Temperate America.
1913.

SMITH, J. B. Our Insect Friends and Enemies. 1909.
THOMSON, J. A. Darwinism and Human Life. 1910.

WEED, C. M., and DEARBORN, N. Birds in Their Relations to
Man (2nd Ed.). 1916.

CHAPTER III

THE CONTROL OF NATURE

Man's earliest arms were fingers, teeth, and nails,
And stones and fragments from the branching woods;
Then copper next: and last, as latest traced,
The tyrant, iron.

- LUCRETIUS.

Man's belief that he is to dominate this earth has never been better expressed than by the poet who first wrote the words: "And God said unto them, Be fruitful and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth." When His Highness, the Elephant, walks down the street of some Indian village, no person challenges his right of way. With one accord he is given a clear road. Yet on his back is a man, diminutive by comparison, to whose orders the giant is obedient. In this simple incident we have an epitome of history. Man is by no means one of the largest and strongest animals of earth. Yet today he is the master. Existence depends upon the use of the facilities offered by nature. Civilization depends upon the direction or control of these facilities for man's benefit. We must be on guard lest we overemphasize the degree of our mastery. By control we really mean the use of the materials of nature to accomplish our ends. We cannot change the law of gravity but we can utilize it to make the weight run the clock or the balloon to rise. We

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