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84 and saucers, a region of peaks and depressions, valleys from which mountains are always in sight.

In this country the annual rainfall is greater in the north than in the south, greater in the high areas than in the low-lying surfaces. The cause of this is obvious when one reﬂects upon the physical phenomenon which produces this arid state,—a fact and a cause not generally recognized by those living within the territory, and often overlooked by those who should know better, as witness the experiments of a few years ago in the endeavor to precipitate moisture in these parts from a cloudless sky. Yet the cause of our Western aridity is very simple, and may be readily understood.

The continent of North America is entered on two sides by great oceanic warm currents. On the eastern side the Gulf Stream moves out of the Gulf of Mexico and up along the coast of Florida, diverging off Hatteras, but its inﬂuence is felt still farther to the north. The other current comes in upon the extreme northwest, and washes the seaboard States of Washington and Northern Oregon, extending across the border and up into British Columbia. These equatorial currents are the tracks along which move the moisture-laden winds; they are the cyclonic belts, the oceanic areas, of the barometric low.

These currents of water-bearing winds hang close to the surface of the warm streams along which they travel and from which they absorb their food-supply; and compatibly with the trend of the streams themselves they are directed at all times from the west toward the east. Now, if our western coast were a low ﬂat plain, we should have no difficulty with aridity in the interior; but such is not the case. Instead of low levels we have high mountains bordering all our west coast contour; the Cascades, the Sierra Nevada, ﬂank the sea from north to south along the whole expanse of the country; they slope toward the ocean, but their summits are high in the cold ether of the heavens. When these low lagging water-soaked winds push in upon the continent, they are met upon the threshold by vast rearing elevations which force them to carry their burdens at once into higher strata of the atmosphere. As they crawl these slopes and strike the cold air above, the warmth is instantly wrung out of them and they are clapped together in a pressure of condensation; they divest themselves of their vapors, lose their humid holdings, and ﬂy across the snowy crests as cold and nearly dry winds.

From thence on, the ﬂight of these winds is across a succession of mountain eminences, upon all of which they leave some of the little moisture which they rescued from the cloud-wringing process upon the coast ranges, until they strike the Rockies; here, among the loftiest altitudes yet encountered, they deposit the last vestige of their oceanic absorption. Thence onward they raise their temperature and drink up rapidly from whatever water surfaces they ﬁnd to attack, quickly reﬁlling their parched atoms from the rivers and great lakes, sending back under-currents to precipitate and refresh as far to the west again as the 99th meridian.

Thus it can be seen that our arid region is such from a defect in nature,—if it may be so regarded,—and it must be considered with this