A brilliant list of honoured names indeed; but the facts of physical Astronomy speak even more strongly than these names in favour of the presence of life, of even organized life, on other Planets. Thus in four meteorites which fell respectively at Alais in France, in the Cape of Good Hope, in Hungary, and again in France, on analysis, there was found graphite, a form of carbon known to be invariably associated with organic life on this Earth of ours. And that the presence of this carbon is not due to any action occurring within our atmosphere is shown by the fact that carbon has been found in the very centre of a meteorite; while in one which fell at Argueil, in the south of France, in 1857, there was found water and turf, the latter being always formed by the decomposition of vegetable substances.
And further, examining the astronomical conditions of the other Planets, it is easy to show that several are far better adapted for the development of life and intelligence—even under the conditions with which men are acquainted—than is our Earth. For instance, on the Planet Jupiter the seasons, instead of varying between wide limits as [pg 747] do ours, change by almost imperceptible degrees, and last twelve times as long as ours. Owing to the inclination of its axis the seasons on Jupiter are due almost entirely to the eccentricity of its orbit, and hence change slowly and regularly. We shall be told, that no life is possible on Jupiter, as it is in an incandescent state. But not all Astronomers agree with this. For instance, what we state is declared by M. Flammarion; and he ought to know.
On the other hand Venus would be less adapted for human life such as exists on Earth, since its seasons are more extreme and its changes of temperature more sudden; though it is curious that the duration of the day is nearly the same on the four inner planets, Mercury, Venus, the Earth and Mars.
On Mercury, the Sun's heat and light are seven times what they are on the Earth, and Astronomy teaches that it is enveloped in a very dense atmosphere. And as we see that life appears more active on Earth in proportion to the light and heat of the Sun, it would seem more than probable that its intensity is far, far greater on Mercury than here.
Venus, like Mercury, has a very dense atmosphere, as also has Mars, and the snows which cover their poles, the clouds which hide their surface, the geographical configuration of their seas and continents, the variations of seasons and climates, are all closely analogous—at least to the eye of the physical Astronomer. But such facts and the considerations to which they give rise have reference only to the possibility of the existence on these Planets of human life as known on Earth. That some forms of life such as we know are possible on these Planets, has been long since abundantly demonstrated, and it seems perfectly useless to go into detailed questions of the physiology, etc., of these hypothetical inhabitants, since, after all, the reader can arrive only at an imaginary extension of his familiar surroundings. It is better to rest content with the three conclusions which M. Flammarion, whom we have so largely quoted, formulates as rigorous and exact deductions from the known facts and laws of Science.
i. The various forces which were active in the beginning of evolution gave birth to a great variety of beings on the several worlds; both in the organic and inorganic kingdoms.
ii. The animated beings were constituted from the first according to forms and organisms in correlation with the physiological state of each inhabited globe.
iii. The humanities of other worlds differ from us, as much in their inner organization as in their external physical type.
Finally the reader who may be disposed to question the validity of these conclusions as being opposed to the Bible, may be referred to an Appendix in M. Flammarion's work dealing in detail with this question, since in a work like the present it seems unnecessary to point out the logical absurdity of those churchmen who deny the plurality of worlds on the ground of biblical authority.
In this connection we may well recall those days when the burning zeal of the Primitive Church opposed the doctrine of the Earth's rotundity, on the ground that the nations at the Antipodes would be outside the pale of salvation; and again, we may remember how long it took for a nascent Science to break down the idea of a solid firmament, in the grooves of which the stars moved for the special edification of terrestrial humanity.