Since the sun is the first cause of life on our globe, since he is, as we have proved, the origin of life, feeling, and thought, since he is the determining cause of the existence of everything possessing organization upon the earth, why may we not hold that the rays which the sun pours upon the earth and the other planets are nothing else than the emanations from these souls? that they are emissions from the pure spirits dwelling in the central star, directed towards us, and the other planets, under the visible form of rays?
If this hypothesis were accepted, what magnificent, what sublime relations existing between the sun and the globes which gravitate around him, would be revealed to us! A continual exchange would be established between the sun and the surrounding planets, an unbroken circle, an inexhaustible communion, radiant emanations which should generate and maintain activity and motion, thought and sentiment, which should keep the flame of life burning everywhere! Let us think of the emanations from souls dwelling in the sun descending upon the earth in solar rays. Light gives existence to plants, and produces vegetable life, accompanied by sensibility. Plants, having received this sensible germ from the sun, communicate it, aided by heat likewise emanating from the sun, to animals. Let us think of the germs of souls, placed in the breasts of animals, developing themselves, becoming perfected by degrees, from one animal to another, and finishing by becoming incarnate in a human body. Let us think, then, of the superhuman being succeeding to man, springing up into the vast plains of ether, and beginning the series of numerous transmigrations which, from one step to another, will lead him to the summit of the scale of spiritual perfection, from which every material substance has been eliminated, and where the soul, thus exalted to the purest degree of its essence, penetrates into the supreme abode of happiness, and of intellectual and moral power—the sun.
Such may be this endless circle, such this unbroken chain, binding together all beings in nature, and passing from the visible to the invisible world.
To those persons who may declaim with severity against the system which we have ventured to put forward, we shall put a question which cannot fail to embarrass them, for science has never been able to solve it. We shall ask them how the light of the sun, and the heat which results from it, are maintained? It is evident that the enormous quantities of heat and light which the sun sends out in torrents into space, must come from a source which cannot be inexhaustible, which has need of renewal, otherwise the sun would become extinct. As there is no effect without a cause, it is plain that the inconceivable quantity of forces which the sun distributes by his burning rays, must be derived from some place. M. Guillemin, in his work on the sun, passes in review the different theories which have been adopted, up to the present day, to explain solar radiation. The following is an analysis of a chapter of M. Guillemin's work on the "Maintenance of Solar Radiation."
Pouillet has calculated that if the sun were not supplied with something to make up for the losses he sustains, he must cool at the rate of one degree in a century. But this calculation falls short of the truth. Pouillet supposed that the specific heat of the sun is the greatest which can be conceived. The specific heat of the sun is, it is true, unknown, but instead of placing it at the maximum power, which it is not proved to be, we might suppose it, by an allowable hypothesis, to be equal to that of water, which is well known. Now if we grant to the sun the specific heat of water, we rectify Pouillet's calculation, and we arrive at the conclusion that the sun, if not furnished with any resources from which to repair his losses, would be entirely extinct at the end of 10,000 years. Professor Tyndall, whose experiments are more recent than those of Pouillet, and inspire greater confidence, says: "If the sun were a block of coal, and it were supplied with sufficient oxygen to enable it to burn at the degree of heat proper to that star, it would be entirely consumed at the end of 5000 years." Now the sun has existed for millions of years, for the transition periods of our globe, in which the first living beings were manifested, are traced back to millions of years. And yet his heat has not sensibly diminished since those distant ages. The proof that it has not diminished, is that the climates of the globe at the present time are the same as they were in the tertiary or quaternary epoch. In the tertiary or quaternary strata the same plants and the same animals which exist at present are found. Speaking of times nearer to our own, we may observe that the productions of the soil remain unchanged during the 2000 or 3000 years, whose traditions and historical archives we possess.
The sun has lost none of his heat during millions of years. Where has he gotten this heat from? Where does he get it from now? By what means is that unquenched fire kept up.
To this question neither astronomy nor physics has ever furnished a satisfactory reply. Treatises, whether astronomical or physical, give us nothing but hypotheses, which we cannot accept.
At first it was said that the sun, turning on his axis in twenty-five days, produced by this movement a perpetual friction of his surface against the element in which he moves, in other words, against the ether. But if that were the case, this friction ought to engender a similar heat on the surface of the planets, whose rotatory motion, and especially the motion of translation in their orbit, is much more rapid than that of the sun turning on his axis. Besides, if we calculate the elevation of the temperature which would result from the friction of the sun against the ether, we shall find that the heat would hardly suffice to maintain the radiation of the solar star during one century. This hypothesis is therefore untenable.
Another theory, better supported, has been put forward by the physicists Mayer, Watterston, and Thompson; it explains the maintenance of the solar heat by a constant fall of meteors on the surface of the solar star.