Mars commonly looks red, when seen without a telescope. If seen through a telescope, greenish and purplish patches are found. It is very likely that the one color shows land and the other water. Since Mars has water-vapor in the air, and probably snow and ice at the poles, he is pretty sure to have oceans also. But the continents and oceans of Mars are differently shaped from ours. There seems to be more of land and less of sea. [Illustration: _Mars. August 22 and 29, 1892._] Thus in a good many ways Mars is not so very unlike our Earth, his next-door neighbor. Day and night seem to be much the same in both worlds, also summer and winter. We think, too, that we find there air and water, snow and ice, lands and seas, changes of weather and differences of climate, more or less like those of the Earth. But if you ask me whether animals and men and women and children live on Mars, I can only say that _nobody knows_. It may not be impossible, so far as we are able to judge. We feel pretty sure that no living creatures such as we ever see on the Earth could exist on the Moon or the Sun. And with Mercury, if not also with Venus, we are hardly less sure, when we think of the intense glare and awful heat in which those two worlds travel. With Mars there is some difference. Knowing the little we do know, it certainly seems a thing by no means out of the question that living creatures _might_ find a home on Mars--creatures not utterly unlike those upon the Earth. But we cannot for a moment say that they do. One difference between Mars and the Earth which would make life there very unlike life on the Earth is its small size. On Mars, as on the Earth, there is the “pull” of attraction. “Downward” all round the planet is towards the centre of Mars, and “upward” all round is towards the sky of Mars; and everything in Mars is heavy towards the centre of the planet. But the _pull_ there is much less than here, because Mars is so small; and the less pull means less weight. A lump of iron which weighs ten pounds on the Earth would weigh less than five pounds on Mars. If a man went to Mars he would be as light there as a boy on the Earth; and if a boy went there he would weigh as little as a baby on the Earth. The two moons which travel with Mars are very tiny, perhaps only about eight or ten miles through. Between the planet Mars and the planet Jupiter lies an enormous gap of millions of miles empty of all large worlds, even of worlds as big as our Moon. Somewhere about the middle of that vast gap, about half-way between Mars and Jupiter, is the belt of PLANETOIDS. Less than four hundred of them are as yet actually known to us; but perhaps thousands of them may be there. Each of these tiny planets has its own pathway round the Sun, and their pathways do not keep nearly to the level of the Earth’s pathway, like those of the bigger worlds.