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traction engine carrying behind an arm, from which is suspended a wheel. Attached to this wheel are buckets. As the wheel rotates, each bucket takes a little earth from the ditch, and when the bucket arrives at its highest point the contents are deposited on a belt conveyor and carried to one side. Directly behind the wheel and slightly under it is the shoe in which the tilelayer stands at his work. The machine will dig a ditch eight feet deep at the rate of a thousand feet an hour if everything runs smoothly. On account of the nature of the ground in which it generally works the machine seldom makes over three thousand feet a day. The tile is laid as the machine progresses to prevent the delay that would be occasioned by the continual cave-ins in the wet ground. One or more shovelers follow closely behind the machine and keep the tile well covered so that if the sides of the ditch do cave in the tile will not be displaced. In ground where the constant water level is very close to the surface the tile layer will sometimes be forced to leave the shoe because of the rapid rise of water in it. Operations must then be suspended until the surplus water is carried off by the tile already laid. The total cost per foot of laying tile with this machine is from eighteen to twenty-five cents. The cost of operating the machine is from four to ten cents per linear foot. The total cost of ditching a field amounts to from six to ten dollars an acre as a rule, although on some work it will run as high as thirty and forty dollars per acre.

A few years ago a man bought a section of salt-grass land on the Pecos River. He ditched and tiled it by hand and bored a shallow artesian well. People called him foolish to try to do anything with that land but he spent one summer washing it and today has the most beautiful place in the valley. The land next adjoining his is a barren alkali flat while his farm is a paradise of green trees and alfalfa fields.

Another man, a land speculator, bought eighty acres of creek bottom, heavily alkalied and with the water level but six inches from the surface. It required 8,500 feet of six and eight inch tile to drain it and the ditching company charged him twenty-five cents a foot for

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the work because of the treacherous lars while they may. Now, however, nature of the earth which caved in con- that some one else has shown the way, tinually. It was like digging in thick the land owners are beginning to realize soup, and the tilelayer was forced from what a big proposition they have. Their the shoe many times a day while the alkalied flats and salt-grass bottoms are whole crew waited for the water to drain likely to make them rich. At no cost to away. The cost was over $2,500 but the the ranchman the government will show job was a success. The land cost the him how to raise crops where he thought speculator a little over a thousand dollars crops would never grow, and more than and, planted to milo maize, it sold for that the government will detail a com$15,500.

petent man to boss the job and see that As is usual with anything new, the the washing is properly and thoroughly legitimate farmers who really need the done. And the ranchman forgets about benefit of his knowledge seldom apply to state's rights and public domain and the engineer. The greater part of his shouts for “new nationalism" and the work has been done for men like this development of our natural resources. speculator, who are harvesting the dol- His point of view is changed...

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Ne'er take a wife till thou hast a house (and a fire) to put her in.

He's gone and forgot nothing but to say farewell to his creditors.

Great Talkers, Little Doers.

Fools make feasts, and wise men eat them.

To lengthen thy life, lessen thy meals.

Many estates are spent in the getting.
He that lieth down with dogs, shall rise up with Aleas.

Tongue double, brings trouble.

MYSTERY OF THE GLACIER

By

EDWIN WALTERS

7 HY is the glacier ?

in a glaciated area? What are the relaIt is a question that tions of glaciers to stationary ice-fields ? has been asked ever since How is loess deposited ? Why the irregumen first stood at the lar distribution of bowlders or "lost

face of one of the great rocks”? Why are these bowlders more ice-fields, that claws its irresistible fur- abundant along certain lines ? row across the earth's tortured surface, These and scores of similar questions and wondered. Most overwhelming of occur to the inquiring mind. And the the agents that change the face of answers to some of these questions are things terrestrial from age to age, it has not to be found in any text-book, enbeen least understood by humans because cyclopedia or other publication. its secrets have lain hidden beneath the The writer has spent weeks on the immensity of Nature's own endless glaciers—and months in the ice-fieldspatience, and our observation has been of Alaska. Observations were made in unable to grasp them from the century- that country that will enable us to add a i slow signs that have come to the surface. few facts to the world's stock of infor

What causes glacial epochs or ice mation on these and kindred subjects. ages? How often do they occur? What The cause of glacial epochs is unsets a glacier in motion? What causes doubtedly the change in the inclination a glacier to cease to move? What causes of the axis of the earth to the plane of a glacier to travel up an incline? What its ecliptic, or pathway through space. are the relations of glaciers to ice-bergs At the end of an astronomical year the

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center of the earth is at the same point one feet in one year. There is a correin space that it occupied at the end of sponding change in the location of the each preceding year. But the angle equator and the other great circles of described by the earth's axis and its the earth. ecliptic has increased in one hemisphere What sets a glacier in motion ? and decreased in the other. This change Snow under pressure becomes ice. in the direction described by the earth's A mountain of ice accumulates bulk and axis brings one hemisphere towards the height until the pressure at its bottom sun, and gives it a warmer climate. This generates heat. Calculating ice at eightchange also turns the opposite hemis- tenths the weight of water, the pressures phere away from the sun, and causes it at the bottoms of glaciers would be as to have a colder climate—to become follows: a glacier 2,000 feet high, 695 more or less glaciated. Thus one hemis- pounds to the square inch; 3,000 feet phere is constantly passing through a high, 1,043 pounds; 4,000 feet high, glacial epoch, or ice age. At the present 1,390 pounds, and 5,000 feet high, 1,738 time the Southern

pounds to the hemisphere is much

square inch. more highly gla

Whenever a ciated than is the

mountain becomes Northern hemis

high enough, from phere. But let it

the accumulation be remembered

of snow on its top, that there is always

to cause the presat least some ice

sure at its base to near the poles-in

generate heat suffiside the Arctic and

cient to raise the Antarctic Circles.

temperature to the During these DIAGRAM ILLUSTRATING WHY GLACIERS MOVE.

melting point, The key to letters will be found in the text, page 315. glacial epochs the

water then comice travels about

mences to accumuone-half of the way from the poles to late beneath the huge mass. the equator—in some instances six- This water must escape—have vent. tenths of the distance, or to the thirty- How? Where? On the side next the sixth parallel of north and south latitude. sun—for the opposite side is much How often do glacial epochs occur? colder, and is closed by frosts.

Astronomers have calculated the an. A number of small streams originate nual change of the inclination of the under an ice-mountain. But they gradearth's axis to be a little less than three- ually merge, and form one large stream. tenths of one second, circular measure. The erosion of the outflowing water on

This change of inclination continues the sunny side of an ice-mountain lowers until the described angle increases to the surface of the earth on that side: twenty-three and one-half degrees—or The mountain topples in that direction. to the Arctic and Antarctic Circles—and Naturally the melting on the sunny side then the change is in the opposite direc- is much more rapid than on the opposite tion. Twenty-three and one-half de- side. So the melting assists in inclining grees equal 84,600 seconds. And 84,600 the mountain in that direction. Finally divided by three-tenths equal 282,000. it commences to move down this eroded The glacial epochs, on this hypothesis, incline, and becomes an active glacier. can not be closer together than 282,000 As soon as motion is set up the earth years. The last glacial epoch in the on the sides bulges or buckles up, from Northern hemisphere commenced about the immense pressure and momentum, 241,000 years ago—and ended about and forms lateral moraines, or longi80,000 years ago, an estimated cycle of tudinal ridges, that are outside of the about 321,000 years.

base of the glacier and that parallel its The change in this angle of inclina- axis. These lateral moraines form a tion is sufficient to change the location trough which confines the water under of the poles between thirty and thirty- the glacier in a continuous stream that

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flows in the direction towards which the through a lateral moraine, and the glacier travels.

glacier above ceases to move the Once in motion a glacier will continue erosion ceases in front and increases to travel until conditions change. Of under the body of the glacier. This course if it travels down an incline, its under erosion will finally cause the motion may be largely from force of glacier to break in two. By this time gravity. It is probable that all of the the escaping stream has eroded an inglaciers of Europe, at the present time, cline on the side of the glacier down are gravity glaciers.

which one piece, or section, of the What causes a glacier to cease its glacier may take motion at an angle of motion ?

from forty to ninety degrees from the There are at least three causes: original line of motion. (a) the underflowing stream may break What causes a glacier to move up an through a lateral moraine and escape at incline ? one side instead of in front of the Glaciers have traveled from the far glacier. This change in the underflowing North to near the thirty-sixth parallel of stream will leave the glacier “dead”; North Latitude. They have crossed hills (b) the glacier may encounter a moun- —even mountains. Sometimes they have tain wall or other obstacle that it can plowed through mountain ranges, as has not surmount nor break down, or (c) the Muir glacier in Alaska. It has cut the immense weight of the glacier, with through a mountain that is at least 3,000 the rapid lowering in front, as already feet high. described, may cause its nose to plow Leaving out of consideration a discusinto the earth deep enough to prevent sion of the explanation of gravity, we motion. When this last cause operates, may regard the phenomenon from the motion is usually but temporarily ar- side of effects only. And so far as rested; for the underflowing stream may effects are concerned, the motion, or erode the terminal, or front, moraine cause of motion, of a gravity glacier is until the glacier is enabled to pursue its easily understood. But what causes original course.

operate to propel a glacier up an incline ? When the underflowing stream breaks When water is at a temperature of

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