by these narrow streaks which he called "canale" or "channels." Unfortunately the word was not translated as "channels" but as "canals," which implies artificial construction, and this latter does therefore not convey the idea which the astronomer sought to convey. These black lines, or "canale," are generally straight and although spoken of as narrow, must be at least 12 miles in width and from a few hundred to three or four thousand miles in length. Starting from points near the polar caps, they follow the arcs of great circles, proceeding to what seem to be centers in the middle of the continent where, most surprisingly, they meet other lines which have come to the same spots. Schiaparelli says that "every channel opens at its end either into a sea or into a lake or into another channel, or else into the intersection of several other channels." "None of them as yet have been seen cut off in the middle of a continent, remaining without beginning or without end. . . . by preference they converge toward the small spots which we have given the names of lakes." These lakes are sometimes several hundred miles in diameter, although many are very much smaller.
The late Dr. Lowell, splendidly equipped with an observatory 7000 feet above sea-level in the clear air of Flagstaff, Arizona, maintained that each "canal" marked the route of a waterway, and that the visible mark is not the "canal" itself, but a broad band of vegetation irrigated from a narrow channel. He studied and mapped 522 of these canals, 56 of which were double. He also mapped the "lakes" which he called "oases." Dr. Lowell wrote a very interesting book on "Mars as the Abode of Life" as a result of his observations. He explains the "strips of vegetation" in this manner:
Since Mars is fast approaching a desert condition, there is a great scarcity of water, the only reliable source of supply coming from the melting of the snows at the polar caps. With the ad-
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