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revolution of 2,200 turns a minute is thus given to the gyroscope. The axis of the Obry or the gyroscopic wheel itself is in line with the longitudinal axis of the torpedo; and, no matter how the torpedo swings to right or left, the gyroscope, because of its inherent directive force, remains in its original position, which is, of course, the direction in which the torpedo was first aimed. Its corrective force is exercised in this way. To the outer ring or gimbal in which the gyroscope is hung, is attached a rod leading to a servo-motor; and, as the torpedo swings to right or left, the gyroscope, remaining stationary, causes the servo-motor-just

Already this article has exceeded its space limit, and yet has left much to be told of these "steel babies," each of which has its own characteristics, and each of which must accordingly be humored and coaxed into perfect working accordingly as they prevail.

It may be of interest to know that the Navy Department is now experimenting with a turbine-driven torpedo with an alcohol superheater, by which still greater range and higher speeds will be attained. For a distance of 1,200 yards a speed of 35 knots is promised; and for a range of 4,000 yards a torpedo is being built that will give a speed of 26 knots. In these

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as with the diving rudders-to operate a rod leading to the vertical rudders, rudders, which, in turn, are brought to a line with the Obry, thereby bringing the torpedo back to the direction of original aim. Under the circumstances, the course of a torpedo is more or less a continuous zigzag; but, because of the rapid corrections of the Obry, the curves of departure are slight. As a result of the introduction of the Obry gear, the range of the torpedo has been increased considerably, and, in a run of 800 yards, a lateral deflection of more than eight yards is prohibitive.

cases, the air chambers are considerably enlarged, and the air is to be stowed in them at a working pressure of 2,250 pounds to the square inch.

Such are the constant advances that are being made; and it will be with such perfected instruments of destruction that we shall meet our enemy if he come in the reasonably near future. One especial significance of the development of the torpedo is that it widens the range of effectiveness of all craft designed to use this device in warfare; and to none will it apply with more force than to the rapidly evolving perfect submarine.

Construction

Possibilities of Reclaiming the Arid and Semi-Arid Lands of the West
and Southwest.-Import of the National Irrigation Act

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Alfalfa, a plant allied to the Clover family, is the great irrigated forage crop of the West. It thrives best under conditions of comparative drouth, and hence is a reliable staple crop in semi-arid regions.

problem yet undertaken by the nation, was greeted with somewhat incredulous smiles and was set down as the phantasies of over-enthusiasm. The new law carried with it an appropriation of about $6,000,000; it also provided that all moneys received from the sales of the public lands of the arid region should be automatically covered into this "reclamation fund." Sales of these lands have been large, and the fund now amounts to about $25,000,000. All of this money

$3,000,000 and $3,500,000. As the work of surveying and reconnoissance has progressed, the claim of the irrigationists of the importance of this work does not seem perhaps so extravagant when it is seen that this government policy-which, doubtless, will later become as broad and comprehensive as our river and harbor construction-contemplates the reclaiming of many million acres of Western desert waste, and transforming it into thousands of productive farms and homes.

Vast Areas Already Irrigated While irrigation is new as a government undertaking, farming by its means is as old as the world's history; and even in the United States, where its practice was begun as a substitute for rainfall, great progress has already been made through private enterprise. The last census figures show that, in round numbers, 7,500,000 acres are irrigated in the western half of the country; and many magnificent stream barrages have been erected to control the floods and form artificial lakes, from which the water can be drained to be applied to the thirsty soil in fertile valleys lying below them.

The greatest disciple of American irrigation was John Wesley Powell, for

the Hydrographic branch of the Geological Survey a well-equipped and wellinformed bureau ready to take up immediately the great work of irrigation engineering construction.

During the last twenty years the Survey has directed its researches throughout the arid West; and Major Powell's mantle now rests upon the competent shoulders of Frederick Haynes Newell, the present National Hydrographer, whose tutelage began under Major Powell some fifteen years ago.

Construction and Development The work of the Geological Survey has been of unquestioned benefit to many of the great private irrigation enterprises

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TYPICAL ATTEMPT AT FARMING WITHOUT IRRIGATION.
Farm Site near St. Anthony, Idaho.

many years Director of the United States
Geological Survey. While not an engi-
neer, Major Powell was an eminent
hydrographer, and, in his wide travels
throughout the arid region, foresaw in a
remarkably accurate degree the ultimate
development through irrigation of that
great region. Many of the sections in the
West, which, as a result of his necessarily
somewhat hasty and superficial recon-
noissances, he prophetically pictured as
having great futures before them
through the storage and utilization of
their water supplies, are now upon the
threshold of that development through
the subsequent accurate surveys of the
Geological Survey; and it was due to his
love for, and belief in, that broad arid
region, that Congress has appropriated at
different times during the past fifteen
years, over a million dollars for its ex-
ploration and survey. When the national
Irrigation Bill became a law, it found in

that have been projected, some of which have been carried to successful completion. There are two distinct phases, however, of the irrigation question-namely, engineering construction, and the application of water to land. Successes in the two branches are by no means coincidental. It is an unfortunate fact that many of the private irrigation works of the West, while they have been great successes from an engineering standpoint, have been failures as irrigation enterprises. This latter fact is due to an insufficiency of the very data which the Government is careful to secure before entering upon any work of construction. An illustrative case is the Sweetwater dam near San Diego, California. This is a magnificent structure of solid masonry; but, owing to a lack of knowledge concerning the average flow of the Sweetwater River, and to the too great confidence and glowing representations

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THE IRRIGATED "ORANGE" VALLEY OF REDLANDS, CALIFORNIA.

Watered largely by pumping from underground sources. Twenty years ago a desert worth only $1.00 an acre.

hundred dollars an acre land to the original desert condition. For some seven years the rainfall on the Sweetwater watershed was insufficient, not only to fill the dam and supply the orange orchards, but even to create a run-off and cover the broad bottom of the reservoir. This splendid dam stands as a monument to the folly of irrigation construction in an arid region without sufficient meteorological and stream-gauging data, and is but an exaggerated example of a large number of projects in the West and particularly the Southwest.

Full Hydrographic Data Essential Too full and complete data cannot be accumulated before entering upon any such great work, for the most serious and heartbreaking experiences are likely to follow upon hasty or ill-advised work of that kind, entailing untold loss and hardship upon the enthusiastic and hopeful settlers, who in many cases stake their all upon the expectation of a good and constant water supply, which, when too late, they discover to be a chimera.

problems involved-the construction of a dam across a canyon, and of great canals to carry the water impounded to the farm laterals. The catchment area

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IRRIGATED PUMPKIN FIELD, CARMEL VALLEY, CALIFORNIA.

must be considered, covering perhaps hundreds of thousands of acres of watershed; and the area of land to be irrigated must be rigorously confined to the certain capacity of the streams flowing into the reservoir. In the West, the Govern

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