True, we can find no trace of an atmosphere in the moon. If there is any atmosphere at all, it must be so thin as to be less than that which we on earth count as actually none. We pump away the air from a glass inclosure in an air-pump, and say the glass is empty. Only it is not quite empty. There is always just a very little air remaining, though so little that fire would not burn and animals could not live in it. Some believe that air, up to that amount, may be found in the moon. But this is much the same as to say there is none at all. For, of course, with either no air or so very little air, life can not possibly exist on the moon. We can not imagine such a thing for a moment. That is just how the matter stands. We “can not imagine,” and therefore we conclude it to be an impossibility. As if we knew a hundredth part of the possibilities in any one corner of God’s great universe! As if our being unable to picture a thing proves that thing not to exist! Suppose we had always lived in tropical heat, and had never seen, known, or heard of such a fact as life in Arctic snows. Should we consider it a thing possible? Suppose we had always lived on dry land, with never a sight of sea or river or pond, and never a proof that animal life could exist under water--aye, and that some living animals may be suffocated by air, just as other living animals are suffocated by water. Should we not, in our wisdom, reason out such a state of affairs to be utterly impossible? There _may_ be no life on the moon. It _may_ be that she is now passing through a dead, cold, blasted stage, either at the close of some past history, or in preparation for some future history--or both. But, on the other hand, it _may_ be that the moon is no less full of life than the earth; only the life must be different in kind, must be something which we do not know any thing at all about. The moon is very much smaller than the earth. Her diameter is about two-sevenths of the earth’s diameter; her entire surface is about two twenty-sevenths of the earth’s surface; her size is about two ninety-ninths of the earth’s size; and her whole weight is about one-eightieth of the earth’s weight. Attraction or gravitation on the surface of the moon is very different from what it is on the earth. Her much smaller bulk greatly lessens her power of attraction. While a man from earth would, on the surface of the sun--supposing he could exist there at all--lie helpless, motionless, and crushed by his own weight, he would on the moon find himself astonishingly light and active. A leap over a tall house would be nothing to him. [Illustration: THE MOON--AN EXPIRED PLANET.]