We see then there are many things to prevent us from leaving our own world and going to the moon. To console ourselves let us guess all we can about it. In the first place I conjecture that the inhabitants must see the heavens, the sun and the stars of a very different colour from what they appear to us. We view those objects through a sort of glass which alters their appearance; this glass is our atmosphere, pervaded with exhalations. Some moderns assert that it is blue as well as the sea, but we can only distinguish the colour in the parts of those elements that are most remote from the eye. The firmament, say they, in which are the fixed stars, has no light in itself, and consequently ought to appear black,[30] but as we see it through our blue air, it seems to us to be blue. If that is true, the rays of the sun and stars cannot pass through the air without receiving a slight tinge from its colour, and losing a degree of that which is natural to them. But supposing the air is not coloured, it is certain that through a thick fog the light of a flambeau, seen at some distance, appears of a deep red, which is not its real colour; if therefore our air be considered only a mist, it must necessarily alter the colour of the sky, sun, and stars. The celestial fluid alone could give us light and colours in their original state. Therefore as the atmosphere of the moon differs from ours, it is either of a different colour, or else it is another sort of mist, which varies the appearance of the celestial bodies. In a word, the glass through which the people in the moon view these objects is of a different nature to ours. [Footnote 30: Desaussure tells us it appears black when viewed at a league's distance from the earth.] On that account, replied the Marchioness, I prefer our world to the moon; I think it impossible for the assortment of colours presented to their sight by the heavenly bodies to be so beautiful as that they form when viewed through the medium of our air. Let us suppose a red sky and green stars; the effect is not so agreeable as golden stars and a blue sky. One would think, said I, you were chusing clothes or furniture; but believe me, nature has a good taste; let us trust to her for providing a set of colours for the moon, there is no fear but it will be a pleasing one. She has undoubtedly varied the appearance of the universe at each different point of view, and in all these varieties there is great beauty.