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sun, or its power of causing heat, is six times greater than with us. If we suppose the mean temperature of Mercury to be the same as of the earth, and the planet to be surrounded with an atmosphere, denser than that of the earth, less capable of transmitting heat, or rather the influence of the sun to extricate heat, and at the same time more readily conducting it to keep up an evenness of temperature, may we not suppose the planet Mercury fit for the habitation of men, and the production of vegetables similar to our own?
“At the Georgium Sidus, the direct influence of the sun is 360 times less than at the earth, and the sun is there seen at an angle not much greater than that under which we behold Venus, when nearest. Yet may not the mean temperature of the Georgium Sidus be nearly the same as that of the earth ? May not its atmosphere more easily transmit the influence of the sun, and may not the matter of heat be more copiously combined, and more readily extricated, than with us? Whence changes of season similar to our own may take place. Even in the comets we may suppose no great change of temperature takes place, as we know of no cause which will deprive them of their mean temperature, and particularly if we suppose, that on their approach towards the sun, there is a provision for their atmosphere becoming denser. The tails they exhibit, when in the neighbourhood of the sun, seem in some measure to countenance this idea.
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“We can hardly suppose the sun, a body three hundred times larger than all the planets together, was created only to preserve the periodic motions, and give light and heat to the planets. Many astronomers have thought that its atmosphere only is luminous, and its body opake, and probably of the same constitution as the planets. Allowing therefore that its luminous atmosphere only extricates heat, we see no reason why the sun itself should not be inhabited k."
There is certainly no end to the suppositions that may be made by an ingenious astronomer. May we not suppose that we might do nearly as well altogether without the sun, which it
appears sent of little use to us as to warmth and heat? As to light, the great creator might, for aught we know, find a substitute ; feelers, for example, endued with a certain acuteness of sense: or, at all events, the least imaginable degree of light might answer every purpose to organs adapted to this kind of twilight. In that way the inhabitants of the Georgium Sidus are already sufficiently provided for; they appear to have as little benefit of the light as of the heat of the sun. How the satellites of the distant planets are supplied with light is a mystery, since their principals have scarcely any. Unless indeed, like the sun, they have a luminous atmosphere, competent to enlighten a whole system, themselves being opake. But in truth light in a
* Brinkley, Elements of Astronomy, Chap. IX.
greater or less degree seems scarcely worthy of a thought, since the inhabitants of the planet Mercury have not their eyes put out by a light, scarcely inferior in radiance to that which is reflected by those plates of burning brass, with which tyrants in some ages were accustomed to extinguish the sense of vision in their unfortunate victims. The comets also must be a delectable residence; that of 1680 completing its orbit in 575 years, and being at its greatest distance about eleven thousand two hundred millions of miles from the sun, and at its least within less than a third part of the sun's semidiameter from its surface'. They must therefore have delightful vicissitudes of light and the contrary; for, as to heat, that is already provided for. Archdeacon Brinkley's postulate is, that these bodies are “possessed by rational beings, and contain animals and vegetables, little different from those with which we are familiar."
Now the only reason we have to believe in these extraordinary propositions, is the knowledge we possess
of the divine attributes. From the force of this consideration it is argued that God will not leave any sensible area of matter unoccupied, and therefore that it is impossible that such vast orbs as we believe surround us even to the extent of infinite space, should not be “ richly stored with rational beings, the capable witnesses of his power, magnificence and benevolence." All difficulties
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arising from the considerations of light, and heat, and a thousand other obstacles, are to give way to the perfect insight we have as to how the deity will conduct himself in every case that can be proposed. I am not persuaded that this is agreeable to religion; and I am still less convinced that it is compatible with the sobriety and sedateness of common sense.
It is with some degree of satisfaction that I perceive lord Brougham, the reputed author of the Preliminary Discourse to the Library of Useful Knowledge, at the same time that he states the dimensions and distances of the heavenly bodies in the usual way, says not a word of their inhabitants.
It is somewhat remarkable that, since the commencement of the present century, four new planets have been added to those formerly contained in the enumeration of the solar system. They lie between the planets Mars and Jupiter, and have been named Vesta, Juno, Ceres and Pallas. Brinkley speaks of them in this manner. “ The very small magnitudes of the new planets Ceres and Pallas, and their nearly equal distances from the sun, induced Dr. Olbers, who discovered Pallas in 1802, nearly in the same place where he had observed Ceres a few months before, to conjecture that they were fragments of a larger planet, which had by some unknown cause been broken to pieces. It follows from the law of gravity, by which the planets are retained in their orbits, that each fragment would again, after every revolution about the
sun, pass nearly through the place in which the planet was when the catastrophe happened, and besides the orbit of each fragment would intersect the continuation of the line joining this place and the sun. Thence it was easy to ascertain the two particular regions of the heavens through which all these fragments would pass. Also, by carefully noting the small stars thereabout, and examining them from time to time, it might be expected that more of the fragments would be discovered. M. Harding discovered the planet Juno in one of these regions; and Dr. Olbers himself also, by carefully examining them (the small stars] from time to time, discovered Vesta.”
These additions certainly afford us a new epoch in the annals of the solar system, and of astronomy itself. It is somewhat remarkable, that Herschel, who in the course of his observations traced certain nebulæ, the light from which must have been two millions of years in reaching the earth, should never have remarked these planets, which, so to speak, lay at his feet. It reminds one of Esop's astrologer, who, to the amusement of his ignorant countrymen, while he was wholly occupied in surveying the heavens, suddenly found himself plunged in a pit. These new planets also we are told are fragments of a larger planet : how came this larger planet never to have been discovered?
Till Herschel's time we were content with six planets and the sun, making up the cabalistical