The other kind is short and sharp. Now it will be remembered that we considered both kinds under the question of atmosphere, and we found both to be explicable as the effect of clouds, but not the effect of mountains. We may therefore feel tolerably certain that Mars is a flat world; devoid, as we may note incidentally, of summer resorts, since it possesses, apparently, neither seas nor hills. To canals we will now return.
The canals so far described all lie in the bright reddish-ochre portions of the disk,— those parts which bear every appearance of being desert. But Mr. Douglass has made the discovery that they are not the only part of the planet thus privileged. He finds, in the very midst of the dark regions themselves, straight, dark streaks not unlike in look to the canals, and still more resembling them in the systematic manner in which they run. For they reproduce the same rectilinear arrangement that is so striking a characteristic of their bright-area fellows. He has succeeded, indeed, in thus triangulating all the more important dark areas. Now this is a very interesting discovery, from several points of view. In the first place, it proves another tell-tale circumstance as to the true character of the so-called seas; for that the seas should be traversed by permanent dark lines is incompatible with a fluid constitution. But