This ether is a true fluid, a gas, analogous to the air we breathe, but infinitely more rarefied and lighter than air. The existence of the planetary ether cannot be disputed, since astronomers take account of its resistance in calculating the speed of heavenly bodies, just as they take account of the resistance of the air in calculating the motions of bodies traversing our atmosphere. Ether is, then, the fluid which succeeds to atmospheric air. It is spread, not only around the earth, but around the other planets. More than this, it exists throughout all space, it occupies the intervals between the planets. It is, in fact, in ether that the planets, which, with their satellites, compose our solar world, revolve. The comets, too, in their immense journeys through space pass through ether. The uneducated mind is disposed to believe that above the air which surrounds the terrestrial globe, there is nothing more, that all is void. But no void exists anywhere in nature. Space is always occupied by something, whether it be by earth, by water, by atmospheric air, or, finally, by _planetary ether_. It has just been said that life abounds upon the globe, swarms upon the earth, clusters in the air and in the waters. Is the ethereal fluid which succeeds to our atmosphere, and which fills space, equally inhabited by living beings? This is a question which no _savant_ has ever yet asked himself. In our opinion, it would be very surprising that life, which we may say overflows in the waters and in the air, should be absolutely wanting in the fluid which is contiguous to the air. Everything, then, indicates that the ether is inhabited. But who are the beings who dwell in the planetary ether? We believe that they are those _superhuman beings_, whom we consider to be resuscitated men, endowed with every kind of moral perfection. The chemical composition of planetary ether is not known. Astronomical phenomena have taught us its existence, but not its components. We believe it may safely be asserted that the ether does not contain oxygen. In fact, oxygen is the fundamental element of atmospheric air; and as, in proportion as they ascend into that air, the respiration of men and animals becomes more and more difficult, it is, in our opinion, presumable, that this difficulty is caused by the approach of a description of gas impossible to breathe; and which, therefore, excludes human life from the superior regions of the air. A man, rising in a balloon towards the ether, is like a fish half drawn out of the water, half exposed to the air. The fish is breathless and palpitating in a place which is fatal to him; thus it is with man, when he rises by degrees through our nether atmosphere, and draws near to the ether. It seems to us that we may, at once, conclude, from this, that there is no oxygen in planetary ether.