THE SOURCE AND MODEOFSOLAR ENERGY.CHAPTER I.STATEMENT OF THE PROBLEM OF SOLAR ENERGY.In endeavoring to present a new and rational interpretation of the source and mode of solar energy, based upon the established principles of recent science, it becomes necessary to briefly cite the facts bearing upon the problem to be solved and the authorities for their support, as well as to describe concisely the different hypotheses at present in vogue, and to point out the well-established insufficiency of these theories, one and all, to account for or explain the difficulties encountered, and which so far have remained as an unsolved enigma. And this problem of solar energy is the grandest and most important question of all physics, for upon the light and heat of the sun depend all physical life and its consequences, animal and vegetable, past, present, and future. If within finite time, and relatively, compared with the enormous vistas of the past, a very brief time, this source ofenergy is to cease, and our whole system be involved in darkness and death, such darkness and death must be eternal; for the dead sun in his final stage of condensation will be as fixed and unchangeable as the operation of eternal laws can make it, and henceforth there can be no revival or reversals, no turning back of the hand upon the dial, while the laws of nature continue; and outside the uniform operation of the laws of nature there is no source, or mode, or continuance of solar energy conceivable. It is true that when our system shall have ran down to its culmination in death, other present systems may continue for a time to exist and new ones spring into being; but these, too, must inevitably follow the same course, and likewise end in eternal darkness, until finally the great experiment of creation shall have ended in eternal failure. The changes we see in progress around us, however, are not of this nature. The individual dies, but the forces which gave life and strength to the race persist, and others will take his place, and the same forces will continue to operate with constant renewals, since we draw our light and heat and life from without; but in the death of suns and their attendant planets there is no analogous process, for such suns are constantly expending their enormous energies in the support of life external to themselves, and only the smallest part of this energy, even, can ever be utilized by themselves or by other suns or planets under any mode of interpretation now in vogue, the boundless realms of so-called inert and empty space receiving the same proportionatequota of light and heat as the almost microscopic points in the sky which constitute the suns and systems we see, and practically all, or nearly all, of this enormous energy is an absolute dead waste; so that whether receiving new supplies from a constant rain of adjacent meteor streams, or from the gradual contraction of the solar volume, the vast realms of space are the useless recipients of what can never return to the sun again, and, of course, in such case the inevitable end can be predicted; for contraction of volume, with a given mass, must have an effective limit, and meteoric aggregation must also find an effective limit, if the planets are not to be thrown out of place as they continue to revolve around the sun.All accepted theories begin with a primordial impulse, the energies of which are of necessity constantly frittered away and wasted, until finally all light and heat and life must cease to exist, and that at a stage in which no further impulse can ever be given, since the whole universe will have passed through every possible stage of degradation down to the final one of universal and eternal death. And yet this is the best that science has to suggest; the only comfort offered us is that it will not happen in our time, and so, “after us the deluge.” The nebular hypothesis, so called, of Laplace, has required much modification, in the light of more recent science, but the essential principles of this theory are still generally accepted, for they fairly well account for the primal connection of the sun and planets, and the position of the centralsun within, with the orbital and rotational planetary movements, as no other theory has yet done. By this theory the limits of our solar system were once occupied by an attenuated gaseous nebula containing within itself all the matter which now forms our solar system. This great nebular mass, primordially assumed, was given by gravity a slow but gradually increasing rotation upon its center; the force of gravity acted more strongly upon this rotating body as it contracted, so that rings of nebulous matter were successively thrown off, which coalesced into single masses and these finally into planets. These planetary globes themselves, as they coalesced and contracted, left behind or threw off rings of their outer matter, which, in turn, became moons, and finally our solar system with its central sun was evolved as we now see it; development continued, the planets cooled and condensed, life appeared when the conditions became suitable, and the original progressive condensation of the central mass—the sun—still continuing, the evolution of light and heat continues, and will continue in a correlative degree. As our moon has passed, apparently, beyond the stage of life, and is cold, airless, waterless, and dead, so will the earth pass; and the larger planets, such as Jupiter and Saturn, which have not yet reached the life stage of condensation, are still hot, but they, too, will pass through the present stage of the earth, then through that in which the moon now is; and the central sun, still glowing, but more and more dimly, will itself pass through thestages in which Jupiter and Saturn now are, then through that of our present earth, and finally into that of the moon, long before which time the emission of all light and heat will have ceased from the sun to its encircling planets, and finally the sun itself will sink into eternal frigidity, and all its store of light and heat will have been dissipated into boundless space, and the possibility of anything resembling what we know as life will have been forever extinguished. In considering the question of the sun’s energy, the author of the article “Sun,” in Appleton’s Cyclopædia, says, “How to account for the supply of the prodigious amount of heat constantly radiated from the solar surface has offered a boundless field of hypothesis. One conjecture is that the sun is now giving off the heat imparted to it at its creation, and that it is gradually cooling down (1). Another ascribed it to combustion (2), and a third to currents of electricity (3). Newton and Buffon conjectured that comets might be the aliment of the sun (4); and of late years a somewhat similar theory (first broached by Mr. Waterston in 1853) has been in vogue,—viz., that a stream of meteoric matter constantly pouring into the sun from the regions of space supplies its heat, by the conversion into it of the arrested motion (5). As the sun may, indeed, derive a small amount of heat from this cause, it deserves more attention than previous conjectures. But conjecture and hypothesis may be said to have given place to views which claim a higher title, as it is now becoming generally recognized, in accordancewith modern physical theories of heat, that in the gravitation of the sun’s mass toward its center, and in its consequent condensation, sufficient heat must be evolved to supply the present radiation, enormous as this undoubtedly is. It appears to be susceptible of full demonstration that a contraction of the sun’s volume of a given definite amount, which is yet so slight as to be invisible to the most powerful telescope, is competent to furnish a heat-supply equal to all that can have been emitted during historical periods. According to this theory, then (which is largely due to the development by Helmholtz of Mayer’s great generalization), the sun’s mass remains unaltered, and its temperature nearly constant, while its size is slowly diminishing as it contracts; so slowly, however, that the supply may be reckoned on through periods almost infinite as measured by the known past of our race, and which are in any case to be counted by millions of years (6).” To these must be added the hypothesis of Dr. Siemens, fully described in Professor Proctor’s “Mysteries of Time and Space.” This ingenious theory, in brief, is that the rotation of the sun on its axis causes a suction in the manner of a fan, at the poles, and a tangential projection, at the equator, of a disk-like stream of gaseous matter into space. The light and heat of the sun, dispersed through space, slowly but continuously act upon the compound gases with which space is universally pervaded to disassociate them into their elements. The disassociated gases thus sucked in at the solar poles at an extremely low temperatureare brought into a state of combustion by friction and condensation, thus generating new supplies of light and heat, and the gases thus reunited by combustion are again projected into space, to be again slowly disassociated by the operation of the sun’s light and heat. The result of this combustion is to form aqueous vapor and carbonic acid and carbonic oxide, and these gases, when disassociated in space, are resolved into carbon, oxygen, and hydrogen, which again and again are thus recombined and again and again decomposed as they pass over the sun’s surface (7).The seven hypotheses above described are the only ones now in vogue, and a brief analysis will show that no single one of them, nor all combined, will give sufficient results to account for the essential difficulties or known conditions of the problem. The first and second hypotheses are answered by the fact set forth by Helmholtz (Popular Scientific Lectures, article “On the Origin of the Planetary System”), that, if the mass of the sun were composed of the two elements capable by combination of producing the greatest possible light and heat,—to wit, hydrogen and oxygen in the proportions in which they unite to form water,—“calculation shows that under the above supposition the heat resulting from their combustion would be sufficient to keep up the radiation of heat from the sun three thousand and twenty-one years. That, it is true, is a long time, but even profane history teaches that the sun has lighted and warmed us for three thousand years, and geology puts it beyond doubtthat this period must be extended to millions of years.”The third hypothesis relates tocurrentsof electricity. We have no knowledge of currents of electricity which could produce, however multiplied or intensified, such light and heat as are constantly poured forth from the sun into all space. That electricity is the intermediate cause of our sun’s energy, and of all solar energy, it is the purpose of this work to demonstrate, but not electriccurrents, which find their attractiveness to theorists in the vague suggestion of which Professor Proctor speaks, referring to comets, in his article on “Cometic Mysteries,” “that perhapsthisis an electrical phenomenon; perhapsthat other featureis electrical, too; perhapsall or mostof the phenomena of comets depend on electricity.” But he adds, “It is so easy to make such suggestions, so difficult to obtain evidence in their favor having the slightest scientific value. Still, I hold the electrical idea to be well worth careful study. Whatever credit may hereafter be given to any electrical theory of comets will be solely and entirely due to those who may help to establish it upon a basis of sound evidence,—none whatever to the mere suggestion, which has been made time and again since it was first advanced by Fontanelle.” It will be seen that the present work, in demonstrating the true source and mode of solar energy, in itself presents a full and sufficient explanation of all the cometic mysteries referred to, as well as all those pertaining to other solar systems in space, and the multifariousphenomena which they present. Indeed, the philosophic mind will not be satisfied with the sufficiency of any hypothesis which will not unlock the mysteries and clearly explain the phenomena of other systems,—of comets, variable and temporary stars, double stars, and all the complicated celestial economy which to the eye of the mere observer presents a bewildering scene of the operation of independent and inscrutable forces. The fifth hypothesis cited, that of meteoric impact, doubtless plays a part, as we know from the generation of light and heat by the constant passage of similar bodies through our own atmosphere. And we know, of course, that the sun, by its vastly-increased attraction, must be subjected to the constant impact of such meteoric bodies in enormous numbers. But the fatal defect in the theory is that such impacts, to produce the radiant energy of the sun, must constantly add to its mass in like proportion, and as the motions and distances of the planets in their orbits are regulated and preserved by virtue of the substantially constant mass of the sun, any progressive and considerable increase in its mass must constantly bring the planets nearer and nearer, and thus increase their orbital velocity. Helmholtz quotes from Sir William Thomson’s investigation, that, “assuming it to hold, the mass of the sun should increase so rapidly that the consequences would have shown themselves in the accelerated motion of the planets. The entire loss of heat from the sun cannot, at all events, be produced in this way; at the most a portion, which, however,may not be inconsiderable.” R. Kalley Miller, in “The Romance of Astronomy,” says, “But more recent observations have led Sir William Thomson to a modification of his theory. He has calculated that if the meteoric shower were sufficiently heavy to make up for the sun’s whole expenditure of heat, the matter of the corona must be so dense as seriously to perturb the orbits of certain comets which pass very close to his surface,—a result which is found not to be the case. But the meteoric theory is only thrown back a step. If the sun’s mass were originally formed, as is not at all improbable, by the agglomeration of these particles, Sir William Thomson has calculated that the heat generated by their thus falling together would be sufficient to account for a supply of twenty million years of solar heat at the present rate of emission. And thus, though the meteors are not sufficient to maintain the energy of our system unimpaired, they may yet have been the original storehouse from which all that energy was derived …. But if the economy of our system be spared long enough, the day must come when the sun with age has become wan; when the matter of the corona has all been drawn in and used up without avail; when the lavish luxuriance with which he has showered abroad his light and heat has finally exhausted all his stores. He has still power, aided by the resisting medium, to drag his satellites one by one down upon his surface; and the shock of each successive impact will, for a brief period, give him a fresh tenure of life. When the earth crashes into thesun it will supply him with a store of heat for nearly a century, while Jupiter’s large mass will extend the period by nearly thirty thousand years. But when the last of the planets is swallowed up, the sun’s energies will rapidly die out and a deep and deathly gloom gather about nature’s grave. Looking into the ages of a future eternity, we can see nothing but a cold and burnt-out mass remaining of that glorious orb which went forth in the morning of time, joyful as a bridegroom from his chamber, and rejoicing as a strong man to run a race.”The sixth hypothesis is that to which most credence is now given. It is that of evolution of energy by condensation of volume. Professor Proctor (“The Sun as a Perpetual Machine”) says, “In company with this great mystery of seeming waste comes the yet more difficult problem, how to explain the apparent continuance of solar light and heat during millions of years. We know from the results of geological research that the earth has been exposed to the action of the solar rays with their present activity during at least a hundred million years. Yet it is difficult to see how, on any hypothesis of the generation of solar heat, or by combining together all possible modes of heat generation, a supply for more than twenty millions of years in the past and a possible supply for as long a period in the future can be accounted for.” Of these vast periods of terrestrial existence in the past we quote the following from a recent publication:“Professor C. D. Wolcott expresses the opinion that geologic time is not to be measured by hundreds of years, but simply by tens of millions. This is widely different from the conclusion arrived at by Sir Charles Lyell, who, basing his estimate on modifications of certain specimens of marine life, assigned 240,000,000 years as the required geological period; Darwin claimed 200,000,000 years; Crowell, about 72,000,000; Geike, from 73,000,000 upward; McGee, Upham, and other recent authorities claim from 100,000,000 up to 680,000,000.”Helmholtz (“On the Origin of the Planetary System”) says, “It is probable rather that a great part of this heat, which was produced by condensation, began to radiate into space before this condensation was complete. But the heat which the sun could have previously developed by its condensation would have been sufficient to cover its present expenditure for not less than 22,000,000 of years of the past …. We may therefore assume with great probability that the sun will still continue in its condensation, even if it only attained the density of the earth, though it will probably become far denser in its interior, owing to its far greater pressure; this would develop fresh quantities of heat, which would be sufficient to maintain for an additional 17,000,000 of years the same intensity of sunshine as that which is now the source of all terrestrial life.” Of this process of condensation Professor Ball, in his recent work, “In the High Heavens,” says, “It goes without saying that the welfare of the human race is necessarilyconnected with the continuance of the sun’s beneficent action. We have indeed shown that the few other direct or indirect sources of heat which might conceivably be relied upon are in the very nature of things devoid of necessary permanence. It becomes, therefore, of the utmost interest to inquire whether the sun’s heat can be calculated on indefinitely. Here is indeed a subject which is literally of the most vital importance, so far as organic life is concerned. If the sun shall ever cease to shine, then it must be certain that there is a term beyond which human existence, or indeed organic existence of any type whatever, cannot any longer endure on the earth. We may say once for all that the sun contains just a certain number of units of heat, actual or potential, and that he is at the present moment shedding that heat around with the most appalling extravagance.” Quoting from Professor Langley, he says, “We feel certain that the incessant radiation from the sun must be producing a profound effect on its stores of energy. The only way of reconciling this with the total absence of evidence of the expected changes is to be found in the supposition that such is the mighty mass of the sun, such the prodigious supply of heat or what is the equivalent of heat which it contains, that the grand transformation through which it is passing proceeds at a rate so slow that, during the ages accessible to our observations, the results achieved have been imperceptible …. We cannot, however, attribute to the sun any miraculous power of generating heat. That great body cannot disobeythose laws which we have learned from experiments in our laboratories. Of course no one now doubts that the great law of the conservation of energy holds good. We do not in the least believe that because the sun’s heat is radiated away in such profusion it is therefore entirely lost. It travels off, no doubt, to the depths of space, andas to what may become of it there we have no information. Everything we know points to the law that energy is as indestructible as matter itself. The heat scattered from the sun exists at least asethereal vibration, if in no other form. But it is most assuredly true that this energy, so copiously dispensed, is lost to our solar system. There is no form in which it is returned, or in which it can be returned. The energy of the system is as surely declining as the store of energy of the clock declines according as the weight runs down. In the clock, however, the energy is restored by winding up the weight, but there is no analogous process known in our system.” The purpose of the present work, however, is to clearly demonstrate that just such a process is actually being carried on, and has been so carried on from the beginning, and will be forever. This writer continues reviewing the suppositions formerly entertained, that the sun was a heated body gradually cooling down, or that it was undergoing absolute combustion, and shows that they were utterly insufficient. He then refers to the theory of meteoric supply, of which he says, “It can, however, be shown that there are not enough meteors in existence to supply a sufficient quantity of heatto the sun to compensate the loss by radiation. The indraught of meteoric matter may, indeed, certainly tend in some small degree to retard the ultimate cooling of the great luminary, but its effect is so small that we can quite afford to overlook it from the point of view that we are taking in these pages. It is to Helmholtz we are indebted for the true solution of the long-vexed problem. He has demonstrated in the clearest manner where the source of the sun’s heat lies …. A gaseous globe like the sun, when it parts with its heat, observes laws of a very different type from those which a cooling solid follows. As the heat disappears by radiation the body contracts; the gaseous object, however, decreases in general much more than a solid body would do for the same loss of heat …. The globe of gas unquestionably radiates heat and loses it, and the globe, in consequence of that loss, shrinks to a smaller size …. In the facts just mentioned we have an explanation of the sustained heat of the sun. Of course we cannot assume that in our calculations the sun is to be treated as if it were gaseous throughout its entire mass, but it approximates so largely to the gaseous state in the greater part of its bulk that we can feel no hesitation in adopting the belief that the true cause has been found.”Regarding the constitution of the sun, it may be stated, however, that we only see its photosphere, which is the visible sun, and the whole volume has a density about that of water; but no man has ever seen the body of the sun itself. In this respect it is like the planet Jupiter: we only know that itsdensity cannot be less than one-fourth the density of the earth’s solid globe. If the photosphere extend to a depth of one thousand, ten thousand, or a hundred thousand miles, the density of the sun’s body or core will be correspondingly increased. Even computing the whole visible volume, the density is far greater than that of any gas we know, even with the solar pressure of gravity; with the sun’s metallic vapors, if the whole core were already vaporized, we would not, to say the least, be likely to observe the sun-spots and other solar phenomena as we find them actually to occur; this, however, will be more fully considered later on. The author continues, “But there is a boundary to the prospect of the continuance of the sun’s radiation. Of course, as the loss of heat goes on the gaseous parts will turn into liquids, and as the process is still further protracted the liquids will transform into solids. Thus, we look forward to a time when the radiation of the sun can be no longer carried on in conformity with the laws which dictate the loss of heat from a gaseous body. When this state is reached the sun may, no doubt, be an incandescent solid with a brilliance as great as is compatible with that condition, but the further loss of heat will then involve loss of temperature …. There seems no escape from the conclusion that the continuous loss of solar heat must still go on, so that the sun will pass through the various stages of brilliant incandescence, of glowing redness, of dull redness, until it ultimately becomes a dark and non-luminous star …. There is thus a distinctlimit to man’s existence on the earth, dictated by the ultimate exhaustion of the sun …. The utmost amount of heat that it would ever have been possible for the sun to contain would, according to this authority (Professor Langley), supply its radiation for eighteen million years at the present rate …. It seems that the sun has already dissipated about four-fifths of the energy with which it may have originally been endowed. At all events, it seems that, radiating energy at its present rate, the sun may hold out for four million years or for five million years, but not for ten million years …. We have seen that it does not seem possible for any other source of heat to be available for replenishing the waning stores of the luminary.” He concludes by saying that the original heat may have been imparted as the result of some great collision, the solar body having itself been dark before the collision occurred, and that it may be reinvigorated by a repetition of a similar startling process, but indicates in general terms that such an operation would be bad for the round world and all contained therein. It would, in fact, be rough treatment for even a hopeless case.Condensation of the solar volume is unquestionably a source of heat, for we know that the solid or liquid interior of the earth increases in temperature at a definite ratio as we descend through its crust; but long before the sun shall have become contracted to the density of the earth all its heat will have become substantially internal heat, and it can then supply no more by radiation to its surrounding planets.It will be seen that the radiant energy of the sun on any of the above hypotheses is not sufficient to account even for the life period of the earth in the past, and that its future period of energy must be still more brief. Professor Ball (“In the High Heavens”), basing his views on Laplace’s “Nebular Hypothesis,” says, “Looking back into the remote ages, we thus see that the sun was larger and larger the further back we project our view. If we go sufficiently far back, we seem to come to a time when the sun, in a more or less completely gaseous state, filled up the surrounding space out to the orbit of Mercury, or, earlier still, out to the orbit of the remotest planet.” According to this hypothesis, all these brilliant suns, the author says, will “settle down into dark bodies like the earth,” and that “every analogy would teach us that the dark and non-luminous bodies in the universe are far more numerous than the brilliant suns. We can never see the dark objects; we can discern their presence only indirectly. All the stars that we can see are merely those bodies which at this epoch of their career happen for the time to be so highly heated as to be luminous …. It may happen that there are dark bodies in the vicinity of some of the bright stars to which these stars act as illuminants, just in the same way as the sun disperses light to the planets.” One would naturally suppose, however, that there must be some sort of laws to govern such stupendous operations, and that nature is not merely engaged in blowing bubbles. To quote Professor Newcomb:“At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature; that it has not been proved to be inconsistent with any fact; that it isalmost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun’s heat; but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation. Should any one be sceptical as to the sufficiency of these laws to account for the present state of things, science can furnish no evidence strong enough to overthrow his doubts until the sun shall be found growing smaller by actual measurement, or the nebulæ be actually seen to condense into stars and systems.”While the validity of the views set forth in the present volume does not depend on the sufficiency or insufficiency of the nebular hypothesis, and in fact requires the condensation as well as the expansion of the solar volumeunder the influence of heatto be recognized and its extreme importance pointed out, yet it must not be supposed that this great generalization of Kant and Laplace, based on the views presented originally by Sir William Herschel, is established, or that the difficulties in its way are not so enormous as to be almost insuperable. Professor Ball points out that thousands of bodies occupy our solar system, and together compose it as a whole; that these have orbits of every sort of eccentricity and direction, and occupying all possible planes which can pass through the sun;that the bodies circle around the sun, some backward and others forward, and that only the planets seem to conform to some common order; and without this order, which may be accidental, so far as our knowledge goes, the system would have been disrupted long since, if it ever could have begun its operations; and that in this view the heavens may be strewn with wrecks of systems which failed to survive from inherent want of harmony,—that is to say, as based on observation only. Whether the nebular hypothesis be a universal or a partial law of development, or whether the real processes be quite different, cannot, however, depend on the continued maintenance and evolution of the sun’s energy, as this source must in truth be sought for in quite a different direction.The remaining hypothesis (the seventh) is considered in detail in Professor Proctor’s work, “Mysteries of Time and Space.” The fatal defect in Dr. Siemens’s theory is, that his gases will not be projected from the sun’s equator. Professor Proctor says, “Thus the centripetal tendency of matter at the sun’s equator is very much greater (many hundreds of times greater) than its centrifugal tendency, and there is not the slightest possibility of matter being projected into space from the sun’s surface by centrifugal tendency. Nor is there any part of the sun’s mass where the centrifugal tendency is greater than at the surface near the equator. So that, whatever else the sun may be doing to utilize his mighty energies, he is certainly not throwing off matter constantly from hisequatorial regions, as Dr. Siemens’s theory requires.” There are other difficulties which Professor Proctor considers, such as the doubt as to the power of the sun’s rays to disassociate combined gases in space, and also that, since both light and heat must be utilized in this work, if the sun’s energies are to be perpetually renewed, these forces would sensibly disappear in work, and the result would be that the fixed stars would be invisible beyond their domains, and their light, when not totally cut off, would be greatly diminished, in any event, as distances increased, which is not the case. Besides, these gases thus disassociated could never be entirely used by the sun, and the remainder would be wasted, and the part wasted would vastly exceed that utilized, probably in as great proportion of waste as that of the sun’s light not utilized by the planets, which gather but one two-hundred-and-thirty-two-millionths of the whole. It may be further added that these gases would be mechanically mixed, the combined and the disassociated, and this would be mostly the case in those parts nearest the sun, so that large volumes of spent and useless gases would have to be carried in to no purpose whatever. In fact, these gases would gradually form a closed circuit of supply and discharge, and surrounding space would be but slightly affected. Professor Proctor concludes, “We have, in fact, the fallacy of perpetual motion in a modified form.”It will be apparent that under any single one, or all, of these hypotheses, the future prospect for created forms and continued existence is hopeless,and that the inevitable result must do violence to every conception of either an intelligent creative power or the operations of universal law. The mind revolts from the continued degradation and destruction of all organic creation, while the malevolent and iconoclastic forces of nature hold high revel over final ruin and eternal destruction, brought about by their own incessant efforts, striking out blindly to make or mar, and they alone the deathless survivors, the half-blind fates and furies of the eternal future. It betokens, not the processes of orderly government, but the reign of anarchy.Note.—Since this work has been in press, at the annual meeting of the British Association, August 8, 1894, Lord Salisbury, the President, delivered a powerful and lucid address on the present status of scientific knowledge and its limitations. With reference to the antiquity of the earth we quote the following: “It is evident, from the increase of heat as we descend into the earth, that the earth is cooling, and we know, by experiment within certain wide limits, the rate at which its substances—the matters of which it is constituted—are found to cool. It follows that we can approximately calculate how hot it was so many million years ago; but if at any time it was hotter at the surface by fifty degrees Fahrenheit than it is now, life would then have been impossible upon the planet, and, therefore, we can without much difficulty fix a date before which organic life on earth cannot have existed. Basing himself on these considerations, Lord Kelvin limited the period of organic life upon the earth to a hundred million years, and Professor Tait, in a still more penurious spirit, cut that hundred down to ten.” If a period of anything like ten million years, even, has been requisite to cool the earth’s surface only fifty degrees in temperature, what time must have elapsed since the terrestrial globe had a temperature high enough to effect the difficult chemical combinations of many of the elements which compose its structure? And even this must have been far less than the vast cycles of time during which original consolidation was effected. Through all these ages the sun must have been pouring out his radiant energy at at least his present rate. Radiation of heat from the earth may have been relatively less rapid from a denser carbon-laden atmosphere in times past than at present, but it never could have been more so. The whole address cited is, indeed, strongly corroborative of the facts upon which the present work is based.
THE SOURCE AND MODEOFSOLAR ENERGY.CHAPTER I.STATEMENT OF THE PROBLEM OF SOLAR ENERGY.In endeavoring to present a new and rational interpretation of the source and mode of solar energy, based upon the established principles of recent science, it becomes necessary to briefly cite the facts bearing upon the problem to be solved and the authorities for their support, as well as to describe concisely the different hypotheses at present in vogue, and to point out the well-established insufficiency of these theories, one and all, to account for or explain the difficulties encountered, and which so far have remained as an unsolved enigma. And this problem of solar energy is the grandest and most important question of all physics, for upon the light and heat of the sun depend all physical life and its consequences, animal and vegetable, past, present, and future. If within finite time, and relatively, compared with the enormous vistas of the past, a very brief time, this source ofenergy is to cease, and our whole system be involved in darkness and death, such darkness and death must be eternal; for the dead sun in his final stage of condensation will be as fixed and unchangeable as the operation of eternal laws can make it, and henceforth there can be no revival or reversals, no turning back of the hand upon the dial, while the laws of nature continue; and outside the uniform operation of the laws of nature there is no source, or mode, or continuance of solar energy conceivable. It is true that when our system shall have ran down to its culmination in death, other present systems may continue for a time to exist and new ones spring into being; but these, too, must inevitably follow the same course, and likewise end in eternal darkness, until finally the great experiment of creation shall have ended in eternal failure. The changes we see in progress around us, however, are not of this nature. The individual dies, but the forces which gave life and strength to the race persist, and others will take his place, and the same forces will continue to operate with constant renewals, since we draw our light and heat and life from without; but in the death of suns and their attendant planets there is no analogous process, for such suns are constantly expending their enormous energies in the support of life external to themselves, and only the smallest part of this energy, even, can ever be utilized by themselves or by other suns or planets under any mode of interpretation now in vogue, the boundless realms of so-called inert and empty space receiving the same proportionatequota of light and heat as the almost microscopic points in the sky which constitute the suns and systems we see, and practically all, or nearly all, of this enormous energy is an absolute dead waste; so that whether receiving new supplies from a constant rain of adjacent meteor streams, or from the gradual contraction of the solar volume, the vast realms of space are the useless recipients of what can never return to the sun again, and, of course, in such case the inevitable end can be predicted; for contraction of volume, with a given mass, must have an effective limit, and meteoric aggregation must also find an effective limit, if the planets are not to be thrown out of place as they continue to revolve around the sun.All accepted theories begin with a primordial impulse, the energies of which are of necessity constantly frittered away and wasted, until finally all light and heat and life must cease to exist, and that at a stage in which no further impulse can ever be given, since the whole universe will have passed through every possible stage of degradation down to the final one of universal and eternal death. And yet this is the best that science has to suggest; the only comfort offered us is that it will not happen in our time, and so, “after us the deluge.” The nebular hypothesis, so called, of Laplace, has required much modification, in the light of more recent science, but the essential principles of this theory are still generally accepted, for they fairly well account for the primal connection of the sun and planets, and the position of the centralsun within, with the orbital and rotational planetary movements, as no other theory has yet done. By this theory the limits of our solar system were once occupied by an attenuated gaseous nebula containing within itself all the matter which now forms our solar system. This great nebular mass, primordially assumed, was given by gravity a slow but gradually increasing rotation upon its center; the force of gravity acted more strongly upon this rotating body as it contracted, so that rings of nebulous matter were successively thrown off, which coalesced into single masses and these finally into planets. These planetary globes themselves, as they coalesced and contracted, left behind or threw off rings of their outer matter, which, in turn, became moons, and finally our solar system with its central sun was evolved as we now see it; development continued, the planets cooled and condensed, life appeared when the conditions became suitable, and the original progressive condensation of the central mass—the sun—still continuing, the evolution of light and heat continues, and will continue in a correlative degree. As our moon has passed, apparently, beyond the stage of life, and is cold, airless, waterless, and dead, so will the earth pass; and the larger planets, such as Jupiter and Saturn, which have not yet reached the life stage of condensation, are still hot, but they, too, will pass through the present stage of the earth, then through that in which the moon now is; and the central sun, still glowing, but more and more dimly, will itself pass through thestages in which Jupiter and Saturn now are, then through that of our present earth, and finally into that of the moon, long before which time the emission of all light and heat will have ceased from the sun to its encircling planets, and finally the sun itself will sink into eternal frigidity, and all its store of light and heat will have been dissipated into boundless space, and the possibility of anything resembling what we know as life will have been forever extinguished. In considering the question of the sun’s energy, the author of the article “Sun,” in Appleton’s Cyclopædia, says, “How to account for the supply of the prodigious amount of heat constantly radiated from the solar surface has offered a boundless field of hypothesis. One conjecture is that the sun is now giving off the heat imparted to it at its creation, and that it is gradually cooling down (1). Another ascribed it to combustion (2), and a third to currents of electricity (3). Newton and Buffon conjectured that comets might be the aliment of the sun (4); and of late years a somewhat similar theory (first broached by Mr. Waterston in 1853) has been in vogue,—viz., that a stream of meteoric matter constantly pouring into the sun from the regions of space supplies its heat, by the conversion into it of the arrested motion (5). As the sun may, indeed, derive a small amount of heat from this cause, it deserves more attention than previous conjectures. But conjecture and hypothesis may be said to have given place to views which claim a higher title, as it is now becoming generally recognized, in accordancewith modern physical theories of heat, that in the gravitation of the sun’s mass toward its center, and in its consequent condensation, sufficient heat must be evolved to supply the present radiation, enormous as this undoubtedly is. It appears to be susceptible of full demonstration that a contraction of the sun’s volume of a given definite amount, which is yet so slight as to be invisible to the most powerful telescope, is competent to furnish a heat-supply equal to all that can have been emitted during historical periods. According to this theory, then (which is largely due to the development by Helmholtz of Mayer’s great generalization), the sun’s mass remains unaltered, and its temperature nearly constant, while its size is slowly diminishing as it contracts; so slowly, however, that the supply may be reckoned on through periods almost infinite as measured by the known past of our race, and which are in any case to be counted by millions of years (6).” To these must be added the hypothesis of Dr. Siemens, fully described in Professor Proctor’s “Mysteries of Time and Space.” This ingenious theory, in brief, is that the rotation of the sun on its axis causes a suction in the manner of a fan, at the poles, and a tangential projection, at the equator, of a disk-like stream of gaseous matter into space. The light and heat of the sun, dispersed through space, slowly but continuously act upon the compound gases with which space is universally pervaded to disassociate them into their elements. The disassociated gases thus sucked in at the solar poles at an extremely low temperatureare brought into a state of combustion by friction and condensation, thus generating new supplies of light and heat, and the gases thus reunited by combustion are again projected into space, to be again slowly disassociated by the operation of the sun’s light and heat. The result of this combustion is to form aqueous vapor and carbonic acid and carbonic oxide, and these gases, when disassociated in space, are resolved into carbon, oxygen, and hydrogen, which again and again are thus recombined and again and again decomposed as they pass over the sun’s surface (7).The seven hypotheses above described are the only ones now in vogue, and a brief analysis will show that no single one of them, nor all combined, will give sufficient results to account for the essential difficulties or known conditions of the problem. The first and second hypotheses are answered by the fact set forth by Helmholtz (Popular Scientific Lectures, article “On the Origin of the Planetary System”), that, if the mass of the sun were composed of the two elements capable by combination of producing the greatest possible light and heat,—to wit, hydrogen and oxygen in the proportions in which they unite to form water,—“calculation shows that under the above supposition the heat resulting from their combustion would be sufficient to keep up the radiation of heat from the sun three thousand and twenty-one years. That, it is true, is a long time, but even profane history teaches that the sun has lighted and warmed us for three thousand years, and geology puts it beyond doubtthat this period must be extended to millions of years.”The third hypothesis relates tocurrentsof electricity. We have no knowledge of currents of electricity which could produce, however multiplied or intensified, such light and heat as are constantly poured forth from the sun into all space. That electricity is the intermediate cause of our sun’s energy, and of all solar energy, it is the purpose of this work to demonstrate, but not electriccurrents, which find their attractiveness to theorists in the vague suggestion of which Professor Proctor speaks, referring to comets, in his article on “Cometic Mysteries,” “that perhapsthisis an electrical phenomenon; perhapsthat other featureis electrical, too; perhapsall or mostof the phenomena of comets depend on electricity.” But he adds, “It is so easy to make such suggestions, so difficult to obtain evidence in their favor having the slightest scientific value. Still, I hold the electrical idea to be well worth careful study. Whatever credit may hereafter be given to any electrical theory of comets will be solely and entirely due to those who may help to establish it upon a basis of sound evidence,—none whatever to the mere suggestion, which has been made time and again since it was first advanced by Fontanelle.” It will be seen that the present work, in demonstrating the true source and mode of solar energy, in itself presents a full and sufficient explanation of all the cometic mysteries referred to, as well as all those pertaining to other solar systems in space, and the multifariousphenomena which they present. Indeed, the philosophic mind will not be satisfied with the sufficiency of any hypothesis which will not unlock the mysteries and clearly explain the phenomena of other systems,—of comets, variable and temporary stars, double stars, and all the complicated celestial economy which to the eye of the mere observer presents a bewildering scene of the operation of independent and inscrutable forces. The fifth hypothesis cited, that of meteoric impact, doubtless plays a part, as we know from the generation of light and heat by the constant passage of similar bodies through our own atmosphere. And we know, of course, that the sun, by its vastly-increased attraction, must be subjected to the constant impact of such meteoric bodies in enormous numbers. But the fatal defect in the theory is that such impacts, to produce the radiant energy of the sun, must constantly add to its mass in like proportion, and as the motions and distances of the planets in their orbits are regulated and preserved by virtue of the substantially constant mass of the sun, any progressive and considerable increase in its mass must constantly bring the planets nearer and nearer, and thus increase their orbital velocity. Helmholtz quotes from Sir William Thomson’s investigation, that, “assuming it to hold, the mass of the sun should increase so rapidly that the consequences would have shown themselves in the accelerated motion of the planets. The entire loss of heat from the sun cannot, at all events, be produced in this way; at the most a portion, which, however,may not be inconsiderable.” R. Kalley Miller, in “The Romance of Astronomy,” says, “But more recent observations have led Sir William Thomson to a modification of his theory. He has calculated that if the meteoric shower were sufficiently heavy to make up for the sun’s whole expenditure of heat, the matter of the corona must be so dense as seriously to perturb the orbits of certain comets which pass very close to his surface,—a result which is found not to be the case. But the meteoric theory is only thrown back a step. If the sun’s mass were originally formed, as is not at all improbable, by the agglomeration of these particles, Sir William Thomson has calculated that the heat generated by their thus falling together would be sufficient to account for a supply of twenty million years of solar heat at the present rate of emission. And thus, though the meteors are not sufficient to maintain the energy of our system unimpaired, they may yet have been the original storehouse from which all that energy was derived …. But if the economy of our system be spared long enough, the day must come when the sun with age has become wan; when the matter of the corona has all been drawn in and used up without avail; when the lavish luxuriance with which he has showered abroad his light and heat has finally exhausted all his stores. He has still power, aided by the resisting medium, to drag his satellites one by one down upon his surface; and the shock of each successive impact will, for a brief period, give him a fresh tenure of life. When the earth crashes into thesun it will supply him with a store of heat for nearly a century, while Jupiter’s large mass will extend the period by nearly thirty thousand years. But when the last of the planets is swallowed up, the sun’s energies will rapidly die out and a deep and deathly gloom gather about nature’s grave. Looking into the ages of a future eternity, we can see nothing but a cold and burnt-out mass remaining of that glorious orb which went forth in the morning of time, joyful as a bridegroom from his chamber, and rejoicing as a strong man to run a race.”The sixth hypothesis is that to which most credence is now given. It is that of evolution of energy by condensation of volume. Professor Proctor (“The Sun as a Perpetual Machine”) says, “In company with this great mystery of seeming waste comes the yet more difficult problem, how to explain the apparent continuance of solar light and heat during millions of years. We know from the results of geological research that the earth has been exposed to the action of the solar rays with their present activity during at least a hundred million years. Yet it is difficult to see how, on any hypothesis of the generation of solar heat, or by combining together all possible modes of heat generation, a supply for more than twenty millions of years in the past and a possible supply for as long a period in the future can be accounted for.” Of these vast periods of terrestrial existence in the past we quote the following from a recent publication:“Professor C. D. Wolcott expresses the opinion that geologic time is not to be measured by hundreds of years, but simply by tens of millions. This is widely different from the conclusion arrived at by Sir Charles Lyell, who, basing his estimate on modifications of certain specimens of marine life, assigned 240,000,000 years as the required geological period; Darwin claimed 200,000,000 years; Crowell, about 72,000,000; Geike, from 73,000,000 upward; McGee, Upham, and other recent authorities claim from 100,000,000 up to 680,000,000.”Helmholtz (“On the Origin of the Planetary System”) says, “It is probable rather that a great part of this heat, which was produced by condensation, began to radiate into space before this condensation was complete. But the heat which the sun could have previously developed by its condensation would have been sufficient to cover its present expenditure for not less than 22,000,000 of years of the past …. We may therefore assume with great probability that the sun will still continue in its condensation, even if it only attained the density of the earth, though it will probably become far denser in its interior, owing to its far greater pressure; this would develop fresh quantities of heat, which would be sufficient to maintain for an additional 17,000,000 of years the same intensity of sunshine as that which is now the source of all terrestrial life.” Of this process of condensation Professor Ball, in his recent work, “In the High Heavens,” says, “It goes without saying that the welfare of the human race is necessarilyconnected with the continuance of the sun’s beneficent action. We have indeed shown that the few other direct or indirect sources of heat which might conceivably be relied upon are in the very nature of things devoid of necessary permanence. It becomes, therefore, of the utmost interest to inquire whether the sun’s heat can be calculated on indefinitely. Here is indeed a subject which is literally of the most vital importance, so far as organic life is concerned. If the sun shall ever cease to shine, then it must be certain that there is a term beyond which human existence, or indeed organic existence of any type whatever, cannot any longer endure on the earth. We may say once for all that the sun contains just a certain number of units of heat, actual or potential, and that he is at the present moment shedding that heat around with the most appalling extravagance.” Quoting from Professor Langley, he says, “We feel certain that the incessant radiation from the sun must be producing a profound effect on its stores of energy. The only way of reconciling this with the total absence of evidence of the expected changes is to be found in the supposition that such is the mighty mass of the sun, such the prodigious supply of heat or what is the equivalent of heat which it contains, that the grand transformation through which it is passing proceeds at a rate so slow that, during the ages accessible to our observations, the results achieved have been imperceptible …. We cannot, however, attribute to the sun any miraculous power of generating heat. That great body cannot disobeythose laws which we have learned from experiments in our laboratories. Of course no one now doubts that the great law of the conservation of energy holds good. We do not in the least believe that because the sun’s heat is radiated away in such profusion it is therefore entirely lost. It travels off, no doubt, to the depths of space, andas to what may become of it there we have no information. Everything we know points to the law that energy is as indestructible as matter itself. The heat scattered from the sun exists at least asethereal vibration, if in no other form. But it is most assuredly true that this energy, so copiously dispensed, is lost to our solar system. There is no form in which it is returned, or in which it can be returned. The energy of the system is as surely declining as the store of energy of the clock declines according as the weight runs down. In the clock, however, the energy is restored by winding up the weight, but there is no analogous process known in our system.” The purpose of the present work, however, is to clearly demonstrate that just such a process is actually being carried on, and has been so carried on from the beginning, and will be forever. This writer continues reviewing the suppositions formerly entertained, that the sun was a heated body gradually cooling down, or that it was undergoing absolute combustion, and shows that they were utterly insufficient. He then refers to the theory of meteoric supply, of which he says, “It can, however, be shown that there are not enough meteors in existence to supply a sufficient quantity of heatto the sun to compensate the loss by radiation. The indraught of meteoric matter may, indeed, certainly tend in some small degree to retard the ultimate cooling of the great luminary, but its effect is so small that we can quite afford to overlook it from the point of view that we are taking in these pages. It is to Helmholtz we are indebted for the true solution of the long-vexed problem. He has demonstrated in the clearest manner where the source of the sun’s heat lies …. A gaseous globe like the sun, when it parts with its heat, observes laws of a very different type from those which a cooling solid follows. As the heat disappears by radiation the body contracts; the gaseous object, however, decreases in general much more than a solid body would do for the same loss of heat …. The globe of gas unquestionably radiates heat and loses it, and the globe, in consequence of that loss, shrinks to a smaller size …. In the facts just mentioned we have an explanation of the sustained heat of the sun. Of course we cannot assume that in our calculations the sun is to be treated as if it were gaseous throughout its entire mass, but it approximates so largely to the gaseous state in the greater part of its bulk that we can feel no hesitation in adopting the belief that the true cause has been found.”Regarding the constitution of the sun, it may be stated, however, that we only see its photosphere, which is the visible sun, and the whole volume has a density about that of water; but no man has ever seen the body of the sun itself. In this respect it is like the planet Jupiter: we only know that itsdensity cannot be less than one-fourth the density of the earth’s solid globe. If the photosphere extend to a depth of one thousand, ten thousand, or a hundred thousand miles, the density of the sun’s body or core will be correspondingly increased. Even computing the whole visible volume, the density is far greater than that of any gas we know, even with the solar pressure of gravity; with the sun’s metallic vapors, if the whole core were already vaporized, we would not, to say the least, be likely to observe the sun-spots and other solar phenomena as we find them actually to occur; this, however, will be more fully considered later on. The author continues, “But there is a boundary to the prospect of the continuance of the sun’s radiation. Of course, as the loss of heat goes on the gaseous parts will turn into liquids, and as the process is still further protracted the liquids will transform into solids. Thus, we look forward to a time when the radiation of the sun can be no longer carried on in conformity with the laws which dictate the loss of heat from a gaseous body. When this state is reached the sun may, no doubt, be an incandescent solid with a brilliance as great as is compatible with that condition, but the further loss of heat will then involve loss of temperature …. There seems no escape from the conclusion that the continuous loss of solar heat must still go on, so that the sun will pass through the various stages of brilliant incandescence, of glowing redness, of dull redness, until it ultimately becomes a dark and non-luminous star …. There is thus a distinctlimit to man’s existence on the earth, dictated by the ultimate exhaustion of the sun …. The utmost amount of heat that it would ever have been possible for the sun to contain would, according to this authority (Professor Langley), supply its radiation for eighteen million years at the present rate …. It seems that the sun has already dissipated about four-fifths of the energy with which it may have originally been endowed. At all events, it seems that, radiating energy at its present rate, the sun may hold out for four million years or for five million years, but not for ten million years …. We have seen that it does not seem possible for any other source of heat to be available for replenishing the waning stores of the luminary.” He concludes by saying that the original heat may have been imparted as the result of some great collision, the solar body having itself been dark before the collision occurred, and that it may be reinvigorated by a repetition of a similar startling process, but indicates in general terms that such an operation would be bad for the round world and all contained therein. It would, in fact, be rough treatment for even a hopeless case.Condensation of the solar volume is unquestionably a source of heat, for we know that the solid or liquid interior of the earth increases in temperature at a definite ratio as we descend through its crust; but long before the sun shall have become contracted to the density of the earth all its heat will have become substantially internal heat, and it can then supply no more by radiation to its surrounding planets.It will be seen that the radiant energy of the sun on any of the above hypotheses is not sufficient to account even for the life period of the earth in the past, and that its future period of energy must be still more brief. Professor Ball (“In the High Heavens”), basing his views on Laplace’s “Nebular Hypothesis,” says, “Looking back into the remote ages, we thus see that the sun was larger and larger the further back we project our view. If we go sufficiently far back, we seem to come to a time when the sun, in a more or less completely gaseous state, filled up the surrounding space out to the orbit of Mercury, or, earlier still, out to the orbit of the remotest planet.” According to this hypothesis, all these brilliant suns, the author says, will “settle down into dark bodies like the earth,” and that “every analogy would teach us that the dark and non-luminous bodies in the universe are far more numerous than the brilliant suns. We can never see the dark objects; we can discern their presence only indirectly. All the stars that we can see are merely those bodies which at this epoch of their career happen for the time to be so highly heated as to be luminous …. It may happen that there are dark bodies in the vicinity of some of the bright stars to which these stars act as illuminants, just in the same way as the sun disperses light to the planets.” One would naturally suppose, however, that there must be some sort of laws to govern such stupendous operations, and that nature is not merely engaged in blowing bubbles. To quote Professor Newcomb:“At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature; that it has not been proved to be inconsistent with any fact; that it isalmost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun’s heat; but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation. Should any one be sceptical as to the sufficiency of these laws to account for the present state of things, science can furnish no evidence strong enough to overthrow his doubts until the sun shall be found growing smaller by actual measurement, or the nebulæ be actually seen to condense into stars and systems.”While the validity of the views set forth in the present volume does not depend on the sufficiency or insufficiency of the nebular hypothesis, and in fact requires the condensation as well as the expansion of the solar volumeunder the influence of heatto be recognized and its extreme importance pointed out, yet it must not be supposed that this great generalization of Kant and Laplace, based on the views presented originally by Sir William Herschel, is established, or that the difficulties in its way are not so enormous as to be almost insuperable. Professor Ball points out that thousands of bodies occupy our solar system, and together compose it as a whole; that these have orbits of every sort of eccentricity and direction, and occupying all possible planes which can pass through the sun;that the bodies circle around the sun, some backward and others forward, and that only the planets seem to conform to some common order; and without this order, which may be accidental, so far as our knowledge goes, the system would have been disrupted long since, if it ever could have begun its operations; and that in this view the heavens may be strewn with wrecks of systems which failed to survive from inherent want of harmony,—that is to say, as based on observation only. Whether the nebular hypothesis be a universal or a partial law of development, or whether the real processes be quite different, cannot, however, depend on the continued maintenance and evolution of the sun’s energy, as this source must in truth be sought for in quite a different direction.The remaining hypothesis (the seventh) is considered in detail in Professor Proctor’s work, “Mysteries of Time and Space.” The fatal defect in Dr. Siemens’s theory is, that his gases will not be projected from the sun’s equator. Professor Proctor says, “Thus the centripetal tendency of matter at the sun’s equator is very much greater (many hundreds of times greater) than its centrifugal tendency, and there is not the slightest possibility of matter being projected into space from the sun’s surface by centrifugal tendency. Nor is there any part of the sun’s mass where the centrifugal tendency is greater than at the surface near the equator. So that, whatever else the sun may be doing to utilize his mighty energies, he is certainly not throwing off matter constantly from hisequatorial regions, as Dr. Siemens’s theory requires.” There are other difficulties which Professor Proctor considers, such as the doubt as to the power of the sun’s rays to disassociate combined gases in space, and also that, since both light and heat must be utilized in this work, if the sun’s energies are to be perpetually renewed, these forces would sensibly disappear in work, and the result would be that the fixed stars would be invisible beyond their domains, and their light, when not totally cut off, would be greatly diminished, in any event, as distances increased, which is not the case. Besides, these gases thus disassociated could never be entirely used by the sun, and the remainder would be wasted, and the part wasted would vastly exceed that utilized, probably in as great proportion of waste as that of the sun’s light not utilized by the planets, which gather but one two-hundred-and-thirty-two-millionths of the whole. It may be further added that these gases would be mechanically mixed, the combined and the disassociated, and this would be mostly the case in those parts nearest the sun, so that large volumes of spent and useless gases would have to be carried in to no purpose whatever. In fact, these gases would gradually form a closed circuit of supply and discharge, and surrounding space would be but slightly affected. Professor Proctor concludes, “We have, in fact, the fallacy of perpetual motion in a modified form.”It will be apparent that under any single one, or all, of these hypotheses, the future prospect for created forms and continued existence is hopeless,and that the inevitable result must do violence to every conception of either an intelligent creative power or the operations of universal law. The mind revolts from the continued degradation and destruction of all organic creation, while the malevolent and iconoclastic forces of nature hold high revel over final ruin and eternal destruction, brought about by their own incessant efforts, striking out blindly to make or mar, and they alone the deathless survivors, the half-blind fates and furies of the eternal future. It betokens, not the processes of orderly government, but the reign of anarchy.Note.—Since this work has been in press, at the annual meeting of the British Association, August 8, 1894, Lord Salisbury, the President, delivered a powerful and lucid address on the present status of scientific knowledge and its limitations. With reference to the antiquity of the earth we quote the following: “It is evident, from the increase of heat as we descend into the earth, that the earth is cooling, and we know, by experiment within certain wide limits, the rate at which its substances—the matters of which it is constituted—are found to cool. It follows that we can approximately calculate how hot it was so many million years ago; but if at any time it was hotter at the surface by fifty degrees Fahrenheit than it is now, life would then have been impossible upon the planet, and, therefore, we can without much difficulty fix a date before which organic life on earth cannot have existed. Basing himself on these considerations, Lord Kelvin limited the period of organic life upon the earth to a hundred million years, and Professor Tait, in a still more penurious spirit, cut that hundred down to ten.” If a period of anything like ten million years, even, has been requisite to cool the earth’s surface only fifty degrees in temperature, what time must have elapsed since the terrestrial globe had a temperature high enough to effect the difficult chemical combinations of many of the elements which compose its structure? And even this must have been far less than the vast cycles of time during which original consolidation was effected. Through all these ages the sun must have been pouring out his radiant energy at at least his present rate. Radiation of heat from the earth may have been relatively less rapid from a denser carbon-laden atmosphere in times past than at present, but it never could have been more so. The whole address cited is, indeed, strongly corroborative of the facts upon which the present work is based.
THE SOURCE AND MODEOFSOLAR ENERGY.CHAPTER I.STATEMENT OF THE PROBLEM OF SOLAR ENERGY.
In endeavoring to present a new and rational interpretation of the source and mode of solar energy, based upon the established principles of recent science, it becomes necessary to briefly cite the facts bearing upon the problem to be solved and the authorities for their support, as well as to describe concisely the different hypotheses at present in vogue, and to point out the well-established insufficiency of these theories, one and all, to account for or explain the difficulties encountered, and which so far have remained as an unsolved enigma. And this problem of solar energy is the grandest and most important question of all physics, for upon the light and heat of the sun depend all physical life and its consequences, animal and vegetable, past, present, and future. If within finite time, and relatively, compared with the enormous vistas of the past, a very brief time, this source ofenergy is to cease, and our whole system be involved in darkness and death, such darkness and death must be eternal; for the dead sun in his final stage of condensation will be as fixed and unchangeable as the operation of eternal laws can make it, and henceforth there can be no revival or reversals, no turning back of the hand upon the dial, while the laws of nature continue; and outside the uniform operation of the laws of nature there is no source, or mode, or continuance of solar energy conceivable. It is true that when our system shall have ran down to its culmination in death, other present systems may continue for a time to exist and new ones spring into being; but these, too, must inevitably follow the same course, and likewise end in eternal darkness, until finally the great experiment of creation shall have ended in eternal failure. The changes we see in progress around us, however, are not of this nature. The individual dies, but the forces which gave life and strength to the race persist, and others will take his place, and the same forces will continue to operate with constant renewals, since we draw our light and heat and life from without; but in the death of suns and their attendant planets there is no analogous process, for such suns are constantly expending their enormous energies in the support of life external to themselves, and only the smallest part of this energy, even, can ever be utilized by themselves or by other suns or planets under any mode of interpretation now in vogue, the boundless realms of so-called inert and empty space receiving the same proportionatequota of light and heat as the almost microscopic points in the sky which constitute the suns and systems we see, and practically all, or nearly all, of this enormous energy is an absolute dead waste; so that whether receiving new supplies from a constant rain of adjacent meteor streams, or from the gradual contraction of the solar volume, the vast realms of space are the useless recipients of what can never return to the sun again, and, of course, in such case the inevitable end can be predicted; for contraction of volume, with a given mass, must have an effective limit, and meteoric aggregation must also find an effective limit, if the planets are not to be thrown out of place as they continue to revolve around the sun.All accepted theories begin with a primordial impulse, the energies of which are of necessity constantly frittered away and wasted, until finally all light and heat and life must cease to exist, and that at a stage in which no further impulse can ever be given, since the whole universe will have passed through every possible stage of degradation down to the final one of universal and eternal death. And yet this is the best that science has to suggest; the only comfort offered us is that it will not happen in our time, and so, “after us the deluge.” The nebular hypothesis, so called, of Laplace, has required much modification, in the light of more recent science, but the essential principles of this theory are still generally accepted, for they fairly well account for the primal connection of the sun and planets, and the position of the centralsun within, with the orbital and rotational planetary movements, as no other theory has yet done. By this theory the limits of our solar system were once occupied by an attenuated gaseous nebula containing within itself all the matter which now forms our solar system. This great nebular mass, primordially assumed, was given by gravity a slow but gradually increasing rotation upon its center; the force of gravity acted more strongly upon this rotating body as it contracted, so that rings of nebulous matter were successively thrown off, which coalesced into single masses and these finally into planets. These planetary globes themselves, as they coalesced and contracted, left behind or threw off rings of their outer matter, which, in turn, became moons, and finally our solar system with its central sun was evolved as we now see it; development continued, the planets cooled and condensed, life appeared when the conditions became suitable, and the original progressive condensation of the central mass—the sun—still continuing, the evolution of light and heat continues, and will continue in a correlative degree. As our moon has passed, apparently, beyond the stage of life, and is cold, airless, waterless, and dead, so will the earth pass; and the larger planets, such as Jupiter and Saturn, which have not yet reached the life stage of condensation, are still hot, but they, too, will pass through the present stage of the earth, then through that in which the moon now is; and the central sun, still glowing, but more and more dimly, will itself pass through thestages in which Jupiter and Saturn now are, then through that of our present earth, and finally into that of the moon, long before which time the emission of all light and heat will have ceased from the sun to its encircling planets, and finally the sun itself will sink into eternal frigidity, and all its store of light and heat will have been dissipated into boundless space, and the possibility of anything resembling what we know as life will have been forever extinguished. In considering the question of the sun’s energy, the author of the article “Sun,” in Appleton’s Cyclopædia, says, “How to account for the supply of the prodigious amount of heat constantly radiated from the solar surface has offered a boundless field of hypothesis. One conjecture is that the sun is now giving off the heat imparted to it at its creation, and that it is gradually cooling down (1). Another ascribed it to combustion (2), and a third to currents of electricity (3). Newton and Buffon conjectured that comets might be the aliment of the sun (4); and of late years a somewhat similar theory (first broached by Mr. Waterston in 1853) has been in vogue,—viz., that a stream of meteoric matter constantly pouring into the sun from the regions of space supplies its heat, by the conversion into it of the arrested motion (5). As the sun may, indeed, derive a small amount of heat from this cause, it deserves more attention than previous conjectures. But conjecture and hypothesis may be said to have given place to views which claim a higher title, as it is now becoming generally recognized, in accordancewith modern physical theories of heat, that in the gravitation of the sun’s mass toward its center, and in its consequent condensation, sufficient heat must be evolved to supply the present radiation, enormous as this undoubtedly is. It appears to be susceptible of full demonstration that a contraction of the sun’s volume of a given definite amount, which is yet so slight as to be invisible to the most powerful telescope, is competent to furnish a heat-supply equal to all that can have been emitted during historical periods. According to this theory, then (which is largely due to the development by Helmholtz of Mayer’s great generalization), the sun’s mass remains unaltered, and its temperature nearly constant, while its size is slowly diminishing as it contracts; so slowly, however, that the supply may be reckoned on through periods almost infinite as measured by the known past of our race, and which are in any case to be counted by millions of years (6).” To these must be added the hypothesis of Dr. Siemens, fully described in Professor Proctor’s “Mysteries of Time and Space.” This ingenious theory, in brief, is that the rotation of the sun on its axis causes a suction in the manner of a fan, at the poles, and a tangential projection, at the equator, of a disk-like stream of gaseous matter into space. The light and heat of the sun, dispersed through space, slowly but continuously act upon the compound gases with which space is universally pervaded to disassociate them into their elements. The disassociated gases thus sucked in at the solar poles at an extremely low temperatureare brought into a state of combustion by friction and condensation, thus generating new supplies of light and heat, and the gases thus reunited by combustion are again projected into space, to be again slowly disassociated by the operation of the sun’s light and heat. The result of this combustion is to form aqueous vapor and carbonic acid and carbonic oxide, and these gases, when disassociated in space, are resolved into carbon, oxygen, and hydrogen, which again and again are thus recombined and again and again decomposed as they pass over the sun’s surface (7).The seven hypotheses above described are the only ones now in vogue, and a brief analysis will show that no single one of them, nor all combined, will give sufficient results to account for the essential difficulties or known conditions of the problem. The first and second hypotheses are answered by the fact set forth by Helmholtz (Popular Scientific Lectures, article “On the Origin of the Planetary System”), that, if the mass of the sun were composed of the two elements capable by combination of producing the greatest possible light and heat,—to wit, hydrogen and oxygen in the proportions in which they unite to form water,—“calculation shows that under the above supposition the heat resulting from their combustion would be sufficient to keep up the radiation of heat from the sun three thousand and twenty-one years. That, it is true, is a long time, but even profane history teaches that the sun has lighted and warmed us for three thousand years, and geology puts it beyond doubtthat this period must be extended to millions of years.”The third hypothesis relates tocurrentsof electricity. We have no knowledge of currents of electricity which could produce, however multiplied or intensified, such light and heat as are constantly poured forth from the sun into all space. That electricity is the intermediate cause of our sun’s energy, and of all solar energy, it is the purpose of this work to demonstrate, but not electriccurrents, which find their attractiveness to theorists in the vague suggestion of which Professor Proctor speaks, referring to comets, in his article on “Cometic Mysteries,” “that perhapsthisis an electrical phenomenon; perhapsthat other featureis electrical, too; perhapsall or mostof the phenomena of comets depend on electricity.” But he adds, “It is so easy to make such suggestions, so difficult to obtain evidence in their favor having the slightest scientific value. Still, I hold the electrical idea to be well worth careful study. Whatever credit may hereafter be given to any electrical theory of comets will be solely and entirely due to those who may help to establish it upon a basis of sound evidence,—none whatever to the mere suggestion, which has been made time and again since it was first advanced by Fontanelle.” It will be seen that the present work, in demonstrating the true source and mode of solar energy, in itself presents a full and sufficient explanation of all the cometic mysteries referred to, as well as all those pertaining to other solar systems in space, and the multifariousphenomena which they present. Indeed, the philosophic mind will not be satisfied with the sufficiency of any hypothesis which will not unlock the mysteries and clearly explain the phenomena of other systems,—of comets, variable and temporary stars, double stars, and all the complicated celestial economy which to the eye of the mere observer presents a bewildering scene of the operation of independent and inscrutable forces. The fifth hypothesis cited, that of meteoric impact, doubtless plays a part, as we know from the generation of light and heat by the constant passage of similar bodies through our own atmosphere. And we know, of course, that the sun, by its vastly-increased attraction, must be subjected to the constant impact of such meteoric bodies in enormous numbers. But the fatal defect in the theory is that such impacts, to produce the radiant energy of the sun, must constantly add to its mass in like proportion, and as the motions and distances of the planets in their orbits are regulated and preserved by virtue of the substantially constant mass of the sun, any progressive and considerable increase in its mass must constantly bring the planets nearer and nearer, and thus increase their orbital velocity. Helmholtz quotes from Sir William Thomson’s investigation, that, “assuming it to hold, the mass of the sun should increase so rapidly that the consequences would have shown themselves in the accelerated motion of the planets. The entire loss of heat from the sun cannot, at all events, be produced in this way; at the most a portion, which, however,may not be inconsiderable.” R. Kalley Miller, in “The Romance of Astronomy,” says, “But more recent observations have led Sir William Thomson to a modification of his theory. He has calculated that if the meteoric shower were sufficiently heavy to make up for the sun’s whole expenditure of heat, the matter of the corona must be so dense as seriously to perturb the orbits of certain comets which pass very close to his surface,—a result which is found not to be the case. But the meteoric theory is only thrown back a step. If the sun’s mass were originally formed, as is not at all improbable, by the agglomeration of these particles, Sir William Thomson has calculated that the heat generated by their thus falling together would be sufficient to account for a supply of twenty million years of solar heat at the present rate of emission. And thus, though the meteors are not sufficient to maintain the energy of our system unimpaired, they may yet have been the original storehouse from which all that energy was derived …. But if the economy of our system be spared long enough, the day must come when the sun with age has become wan; when the matter of the corona has all been drawn in and used up without avail; when the lavish luxuriance with which he has showered abroad his light and heat has finally exhausted all his stores. He has still power, aided by the resisting medium, to drag his satellites one by one down upon his surface; and the shock of each successive impact will, for a brief period, give him a fresh tenure of life. When the earth crashes into thesun it will supply him with a store of heat for nearly a century, while Jupiter’s large mass will extend the period by nearly thirty thousand years. But when the last of the planets is swallowed up, the sun’s energies will rapidly die out and a deep and deathly gloom gather about nature’s grave. Looking into the ages of a future eternity, we can see nothing but a cold and burnt-out mass remaining of that glorious orb which went forth in the morning of time, joyful as a bridegroom from his chamber, and rejoicing as a strong man to run a race.”The sixth hypothesis is that to which most credence is now given. It is that of evolution of energy by condensation of volume. Professor Proctor (“The Sun as a Perpetual Machine”) says, “In company with this great mystery of seeming waste comes the yet more difficult problem, how to explain the apparent continuance of solar light and heat during millions of years. We know from the results of geological research that the earth has been exposed to the action of the solar rays with their present activity during at least a hundred million years. Yet it is difficult to see how, on any hypothesis of the generation of solar heat, or by combining together all possible modes of heat generation, a supply for more than twenty millions of years in the past and a possible supply for as long a period in the future can be accounted for.” Of these vast periods of terrestrial existence in the past we quote the following from a recent publication:“Professor C. D. Wolcott expresses the opinion that geologic time is not to be measured by hundreds of years, but simply by tens of millions. This is widely different from the conclusion arrived at by Sir Charles Lyell, who, basing his estimate on modifications of certain specimens of marine life, assigned 240,000,000 years as the required geological period; Darwin claimed 200,000,000 years; Crowell, about 72,000,000; Geike, from 73,000,000 upward; McGee, Upham, and other recent authorities claim from 100,000,000 up to 680,000,000.”Helmholtz (“On the Origin of the Planetary System”) says, “It is probable rather that a great part of this heat, which was produced by condensation, began to radiate into space before this condensation was complete. But the heat which the sun could have previously developed by its condensation would have been sufficient to cover its present expenditure for not less than 22,000,000 of years of the past …. We may therefore assume with great probability that the sun will still continue in its condensation, even if it only attained the density of the earth, though it will probably become far denser in its interior, owing to its far greater pressure; this would develop fresh quantities of heat, which would be sufficient to maintain for an additional 17,000,000 of years the same intensity of sunshine as that which is now the source of all terrestrial life.” Of this process of condensation Professor Ball, in his recent work, “In the High Heavens,” says, “It goes without saying that the welfare of the human race is necessarilyconnected with the continuance of the sun’s beneficent action. We have indeed shown that the few other direct or indirect sources of heat which might conceivably be relied upon are in the very nature of things devoid of necessary permanence. It becomes, therefore, of the utmost interest to inquire whether the sun’s heat can be calculated on indefinitely. Here is indeed a subject which is literally of the most vital importance, so far as organic life is concerned. If the sun shall ever cease to shine, then it must be certain that there is a term beyond which human existence, or indeed organic existence of any type whatever, cannot any longer endure on the earth. We may say once for all that the sun contains just a certain number of units of heat, actual or potential, and that he is at the present moment shedding that heat around with the most appalling extravagance.” Quoting from Professor Langley, he says, “We feel certain that the incessant radiation from the sun must be producing a profound effect on its stores of energy. The only way of reconciling this with the total absence of evidence of the expected changes is to be found in the supposition that such is the mighty mass of the sun, such the prodigious supply of heat or what is the equivalent of heat which it contains, that the grand transformation through which it is passing proceeds at a rate so slow that, during the ages accessible to our observations, the results achieved have been imperceptible …. We cannot, however, attribute to the sun any miraculous power of generating heat. That great body cannot disobeythose laws which we have learned from experiments in our laboratories. Of course no one now doubts that the great law of the conservation of energy holds good. We do not in the least believe that because the sun’s heat is radiated away in such profusion it is therefore entirely lost. It travels off, no doubt, to the depths of space, andas to what may become of it there we have no information. Everything we know points to the law that energy is as indestructible as matter itself. The heat scattered from the sun exists at least asethereal vibration, if in no other form. But it is most assuredly true that this energy, so copiously dispensed, is lost to our solar system. There is no form in which it is returned, or in which it can be returned. The energy of the system is as surely declining as the store of energy of the clock declines according as the weight runs down. In the clock, however, the energy is restored by winding up the weight, but there is no analogous process known in our system.” The purpose of the present work, however, is to clearly demonstrate that just such a process is actually being carried on, and has been so carried on from the beginning, and will be forever. This writer continues reviewing the suppositions formerly entertained, that the sun was a heated body gradually cooling down, or that it was undergoing absolute combustion, and shows that they were utterly insufficient. He then refers to the theory of meteoric supply, of which he says, “It can, however, be shown that there are not enough meteors in existence to supply a sufficient quantity of heatto the sun to compensate the loss by radiation. The indraught of meteoric matter may, indeed, certainly tend in some small degree to retard the ultimate cooling of the great luminary, but its effect is so small that we can quite afford to overlook it from the point of view that we are taking in these pages. It is to Helmholtz we are indebted for the true solution of the long-vexed problem. He has demonstrated in the clearest manner where the source of the sun’s heat lies …. A gaseous globe like the sun, when it parts with its heat, observes laws of a very different type from those which a cooling solid follows. As the heat disappears by radiation the body contracts; the gaseous object, however, decreases in general much more than a solid body would do for the same loss of heat …. The globe of gas unquestionably radiates heat and loses it, and the globe, in consequence of that loss, shrinks to a smaller size …. In the facts just mentioned we have an explanation of the sustained heat of the sun. Of course we cannot assume that in our calculations the sun is to be treated as if it were gaseous throughout its entire mass, but it approximates so largely to the gaseous state in the greater part of its bulk that we can feel no hesitation in adopting the belief that the true cause has been found.”Regarding the constitution of the sun, it may be stated, however, that we only see its photosphere, which is the visible sun, and the whole volume has a density about that of water; but no man has ever seen the body of the sun itself. In this respect it is like the planet Jupiter: we only know that itsdensity cannot be less than one-fourth the density of the earth’s solid globe. If the photosphere extend to a depth of one thousand, ten thousand, or a hundred thousand miles, the density of the sun’s body or core will be correspondingly increased. Even computing the whole visible volume, the density is far greater than that of any gas we know, even with the solar pressure of gravity; with the sun’s metallic vapors, if the whole core were already vaporized, we would not, to say the least, be likely to observe the sun-spots and other solar phenomena as we find them actually to occur; this, however, will be more fully considered later on. The author continues, “But there is a boundary to the prospect of the continuance of the sun’s radiation. Of course, as the loss of heat goes on the gaseous parts will turn into liquids, and as the process is still further protracted the liquids will transform into solids. Thus, we look forward to a time when the radiation of the sun can be no longer carried on in conformity with the laws which dictate the loss of heat from a gaseous body. When this state is reached the sun may, no doubt, be an incandescent solid with a brilliance as great as is compatible with that condition, but the further loss of heat will then involve loss of temperature …. There seems no escape from the conclusion that the continuous loss of solar heat must still go on, so that the sun will pass through the various stages of brilliant incandescence, of glowing redness, of dull redness, until it ultimately becomes a dark and non-luminous star …. There is thus a distinctlimit to man’s existence on the earth, dictated by the ultimate exhaustion of the sun …. The utmost amount of heat that it would ever have been possible for the sun to contain would, according to this authority (Professor Langley), supply its radiation for eighteen million years at the present rate …. It seems that the sun has already dissipated about four-fifths of the energy with which it may have originally been endowed. At all events, it seems that, radiating energy at its present rate, the sun may hold out for four million years or for five million years, but not for ten million years …. We have seen that it does not seem possible for any other source of heat to be available for replenishing the waning stores of the luminary.” He concludes by saying that the original heat may have been imparted as the result of some great collision, the solar body having itself been dark before the collision occurred, and that it may be reinvigorated by a repetition of a similar startling process, but indicates in general terms that such an operation would be bad for the round world and all contained therein. It would, in fact, be rough treatment for even a hopeless case.Condensation of the solar volume is unquestionably a source of heat, for we know that the solid or liquid interior of the earth increases in temperature at a definite ratio as we descend through its crust; but long before the sun shall have become contracted to the density of the earth all its heat will have become substantially internal heat, and it can then supply no more by radiation to its surrounding planets.It will be seen that the radiant energy of the sun on any of the above hypotheses is not sufficient to account even for the life period of the earth in the past, and that its future period of energy must be still more brief. Professor Ball (“In the High Heavens”), basing his views on Laplace’s “Nebular Hypothesis,” says, “Looking back into the remote ages, we thus see that the sun was larger and larger the further back we project our view. If we go sufficiently far back, we seem to come to a time when the sun, in a more or less completely gaseous state, filled up the surrounding space out to the orbit of Mercury, or, earlier still, out to the orbit of the remotest planet.” According to this hypothesis, all these brilliant suns, the author says, will “settle down into dark bodies like the earth,” and that “every analogy would teach us that the dark and non-luminous bodies in the universe are far more numerous than the brilliant suns. We can never see the dark objects; we can discern their presence only indirectly. All the stars that we can see are merely those bodies which at this epoch of their career happen for the time to be so highly heated as to be luminous …. It may happen that there are dark bodies in the vicinity of some of the bright stars to which these stars act as illuminants, just in the same way as the sun disperses light to the planets.” One would naturally suppose, however, that there must be some sort of laws to govern such stupendous operations, and that nature is not merely engaged in blowing bubbles. To quote Professor Newcomb:“At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature; that it has not been proved to be inconsistent with any fact; that it isalmost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun’s heat; but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation. Should any one be sceptical as to the sufficiency of these laws to account for the present state of things, science can furnish no evidence strong enough to overthrow his doubts until the sun shall be found growing smaller by actual measurement, or the nebulæ be actually seen to condense into stars and systems.”While the validity of the views set forth in the present volume does not depend on the sufficiency or insufficiency of the nebular hypothesis, and in fact requires the condensation as well as the expansion of the solar volumeunder the influence of heatto be recognized and its extreme importance pointed out, yet it must not be supposed that this great generalization of Kant and Laplace, based on the views presented originally by Sir William Herschel, is established, or that the difficulties in its way are not so enormous as to be almost insuperable. Professor Ball points out that thousands of bodies occupy our solar system, and together compose it as a whole; that these have orbits of every sort of eccentricity and direction, and occupying all possible planes which can pass through the sun;that the bodies circle around the sun, some backward and others forward, and that only the planets seem to conform to some common order; and without this order, which may be accidental, so far as our knowledge goes, the system would have been disrupted long since, if it ever could have begun its operations; and that in this view the heavens may be strewn with wrecks of systems which failed to survive from inherent want of harmony,—that is to say, as based on observation only. Whether the nebular hypothesis be a universal or a partial law of development, or whether the real processes be quite different, cannot, however, depend on the continued maintenance and evolution of the sun’s energy, as this source must in truth be sought for in quite a different direction.The remaining hypothesis (the seventh) is considered in detail in Professor Proctor’s work, “Mysteries of Time and Space.” The fatal defect in Dr. Siemens’s theory is, that his gases will not be projected from the sun’s equator. Professor Proctor says, “Thus the centripetal tendency of matter at the sun’s equator is very much greater (many hundreds of times greater) than its centrifugal tendency, and there is not the slightest possibility of matter being projected into space from the sun’s surface by centrifugal tendency. Nor is there any part of the sun’s mass where the centrifugal tendency is greater than at the surface near the equator. So that, whatever else the sun may be doing to utilize his mighty energies, he is certainly not throwing off matter constantly from hisequatorial regions, as Dr. Siemens’s theory requires.” There are other difficulties which Professor Proctor considers, such as the doubt as to the power of the sun’s rays to disassociate combined gases in space, and also that, since both light and heat must be utilized in this work, if the sun’s energies are to be perpetually renewed, these forces would sensibly disappear in work, and the result would be that the fixed stars would be invisible beyond their domains, and their light, when not totally cut off, would be greatly diminished, in any event, as distances increased, which is not the case. Besides, these gases thus disassociated could never be entirely used by the sun, and the remainder would be wasted, and the part wasted would vastly exceed that utilized, probably in as great proportion of waste as that of the sun’s light not utilized by the planets, which gather but one two-hundred-and-thirty-two-millionths of the whole. It may be further added that these gases would be mechanically mixed, the combined and the disassociated, and this would be mostly the case in those parts nearest the sun, so that large volumes of spent and useless gases would have to be carried in to no purpose whatever. In fact, these gases would gradually form a closed circuit of supply and discharge, and surrounding space would be but slightly affected. Professor Proctor concludes, “We have, in fact, the fallacy of perpetual motion in a modified form.”It will be apparent that under any single one, or all, of these hypotheses, the future prospect for created forms and continued existence is hopeless,and that the inevitable result must do violence to every conception of either an intelligent creative power or the operations of universal law. The mind revolts from the continued degradation and destruction of all organic creation, while the malevolent and iconoclastic forces of nature hold high revel over final ruin and eternal destruction, brought about by their own incessant efforts, striking out blindly to make or mar, and they alone the deathless survivors, the half-blind fates and furies of the eternal future. It betokens, not the processes of orderly government, but the reign of anarchy.Note.—Since this work has been in press, at the annual meeting of the British Association, August 8, 1894, Lord Salisbury, the President, delivered a powerful and lucid address on the present status of scientific knowledge and its limitations. With reference to the antiquity of the earth we quote the following: “It is evident, from the increase of heat as we descend into the earth, that the earth is cooling, and we know, by experiment within certain wide limits, the rate at which its substances—the matters of which it is constituted—are found to cool. It follows that we can approximately calculate how hot it was so many million years ago; but if at any time it was hotter at the surface by fifty degrees Fahrenheit than it is now, life would then have been impossible upon the planet, and, therefore, we can without much difficulty fix a date before which organic life on earth cannot have existed. Basing himself on these considerations, Lord Kelvin limited the period of organic life upon the earth to a hundred million years, and Professor Tait, in a still more penurious spirit, cut that hundred down to ten.” If a period of anything like ten million years, even, has been requisite to cool the earth’s surface only fifty degrees in temperature, what time must have elapsed since the terrestrial globe had a temperature high enough to effect the difficult chemical combinations of many of the elements which compose its structure? And even this must have been far less than the vast cycles of time during which original consolidation was effected. Through all these ages the sun must have been pouring out his radiant energy at at least his present rate. Radiation of heat from the earth may have been relatively less rapid from a denser carbon-laden atmosphere in times past than at present, but it never could have been more so. The whole address cited is, indeed, strongly corroborative of the facts upon which the present work is based.
In endeavoring to present a new and rational interpretation of the source and mode of solar energy, based upon the established principles of recent science, it becomes necessary to briefly cite the facts bearing upon the problem to be solved and the authorities for their support, as well as to describe concisely the different hypotheses at present in vogue, and to point out the well-established insufficiency of these theories, one and all, to account for or explain the difficulties encountered, and which so far have remained as an unsolved enigma. And this problem of solar energy is the grandest and most important question of all physics, for upon the light and heat of the sun depend all physical life and its consequences, animal and vegetable, past, present, and future. If within finite time, and relatively, compared with the enormous vistas of the past, a very brief time, this source ofenergy is to cease, and our whole system be involved in darkness and death, such darkness and death must be eternal; for the dead sun in his final stage of condensation will be as fixed and unchangeable as the operation of eternal laws can make it, and henceforth there can be no revival or reversals, no turning back of the hand upon the dial, while the laws of nature continue; and outside the uniform operation of the laws of nature there is no source, or mode, or continuance of solar energy conceivable. It is true that when our system shall have ran down to its culmination in death, other present systems may continue for a time to exist and new ones spring into being; but these, too, must inevitably follow the same course, and likewise end in eternal darkness, until finally the great experiment of creation shall have ended in eternal failure. The changes we see in progress around us, however, are not of this nature. The individual dies, but the forces which gave life and strength to the race persist, and others will take his place, and the same forces will continue to operate with constant renewals, since we draw our light and heat and life from without; but in the death of suns and their attendant planets there is no analogous process, for such suns are constantly expending their enormous energies in the support of life external to themselves, and only the smallest part of this energy, even, can ever be utilized by themselves or by other suns or planets under any mode of interpretation now in vogue, the boundless realms of so-called inert and empty space receiving the same proportionatequota of light and heat as the almost microscopic points in the sky which constitute the suns and systems we see, and practically all, or nearly all, of this enormous energy is an absolute dead waste; so that whether receiving new supplies from a constant rain of adjacent meteor streams, or from the gradual contraction of the solar volume, the vast realms of space are the useless recipients of what can never return to the sun again, and, of course, in such case the inevitable end can be predicted; for contraction of volume, with a given mass, must have an effective limit, and meteoric aggregation must also find an effective limit, if the planets are not to be thrown out of place as they continue to revolve around the sun.
All accepted theories begin with a primordial impulse, the energies of which are of necessity constantly frittered away and wasted, until finally all light and heat and life must cease to exist, and that at a stage in which no further impulse can ever be given, since the whole universe will have passed through every possible stage of degradation down to the final one of universal and eternal death. And yet this is the best that science has to suggest; the only comfort offered us is that it will not happen in our time, and so, “after us the deluge.” The nebular hypothesis, so called, of Laplace, has required much modification, in the light of more recent science, but the essential principles of this theory are still generally accepted, for they fairly well account for the primal connection of the sun and planets, and the position of the centralsun within, with the orbital and rotational planetary movements, as no other theory has yet done. By this theory the limits of our solar system were once occupied by an attenuated gaseous nebula containing within itself all the matter which now forms our solar system. This great nebular mass, primordially assumed, was given by gravity a slow but gradually increasing rotation upon its center; the force of gravity acted more strongly upon this rotating body as it contracted, so that rings of nebulous matter were successively thrown off, which coalesced into single masses and these finally into planets. These planetary globes themselves, as they coalesced and contracted, left behind or threw off rings of their outer matter, which, in turn, became moons, and finally our solar system with its central sun was evolved as we now see it; development continued, the planets cooled and condensed, life appeared when the conditions became suitable, and the original progressive condensation of the central mass—the sun—still continuing, the evolution of light and heat continues, and will continue in a correlative degree. As our moon has passed, apparently, beyond the stage of life, and is cold, airless, waterless, and dead, so will the earth pass; and the larger planets, such as Jupiter and Saturn, which have not yet reached the life stage of condensation, are still hot, but they, too, will pass through the present stage of the earth, then through that in which the moon now is; and the central sun, still glowing, but more and more dimly, will itself pass through thestages in which Jupiter and Saturn now are, then through that of our present earth, and finally into that of the moon, long before which time the emission of all light and heat will have ceased from the sun to its encircling planets, and finally the sun itself will sink into eternal frigidity, and all its store of light and heat will have been dissipated into boundless space, and the possibility of anything resembling what we know as life will have been forever extinguished. In considering the question of the sun’s energy, the author of the article “Sun,” in Appleton’s Cyclopædia, says, “How to account for the supply of the prodigious amount of heat constantly radiated from the solar surface has offered a boundless field of hypothesis. One conjecture is that the sun is now giving off the heat imparted to it at its creation, and that it is gradually cooling down (1). Another ascribed it to combustion (2), and a third to currents of electricity (3). Newton and Buffon conjectured that comets might be the aliment of the sun (4); and of late years a somewhat similar theory (first broached by Mr. Waterston in 1853) has been in vogue,—viz., that a stream of meteoric matter constantly pouring into the sun from the regions of space supplies its heat, by the conversion into it of the arrested motion (5). As the sun may, indeed, derive a small amount of heat from this cause, it deserves more attention than previous conjectures. But conjecture and hypothesis may be said to have given place to views which claim a higher title, as it is now becoming generally recognized, in accordancewith modern physical theories of heat, that in the gravitation of the sun’s mass toward its center, and in its consequent condensation, sufficient heat must be evolved to supply the present radiation, enormous as this undoubtedly is. It appears to be susceptible of full demonstration that a contraction of the sun’s volume of a given definite amount, which is yet so slight as to be invisible to the most powerful telescope, is competent to furnish a heat-supply equal to all that can have been emitted during historical periods. According to this theory, then (which is largely due to the development by Helmholtz of Mayer’s great generalization), the sun’s mass remains unaltered, and its temperature nearly constant, while its size is slowly diminishing as it contracts; so slowly, however, that the supply may be reckoned on through periods almost infinite as measured by the known past of our race, and which are in any case to be counted by millions of years (6).” To these must be added the hypothesis of Dr. Siemens, fully described in Professor Proctor’s “Mysteries of Time and Space.” This ingenious theory, in brief, is that the rotation of the sun on its axis causes a suction in the manner of a fan, at the poles, and a tangential projection, at the equator, of a disk-like stream of gaseous matter into space. The light and heat of the sun, dispersed through space, slowly but continuously act upon the compound gases with which space is universally pervaded to disassociate them into their elements. The disassociated gases thus sucked in at the solar poles at an extremely low temperatureare brought into a state of combustion by friction and condensation, thus generating new supplies of light and heat, and the gases thus reunited by combustion are again projected into space, to be again slowly disassociated by the operation of the sun’s light and heat. The result of this combustion is to form aqueous vapor and carbonic acid and carbonic oxide, and these gases, when disassociated in space, are resolved into carbon, oxygen, and hydrogen, which again and again are thus recombined and again and again decomposed as they pass over the sun’s surface (7).
The seven hypotheses above described are the only ones now in vogue, and a brief analysis will show that no single one of them, nor all combined, will give sufficient results to account for the essential difficulties or known conditions of the problem. The first and second hypotheses are answered by the fact set forth by Helmholtz (Popular Scientific Lectures, article “On the Origin of the Planetary System”), that, if the mass of the sun were composed of the two elements capable by combination of producing the greatest possible light and heat,—to wit, hydrogen and oxygen in the proportions in which they unite to form water,—“calculation shows that under the above supposition the heat resulting from their combustion would be sufficient to keep up the radiation of heat from the sun three thousand and twenty-one years. That, it is true, is a long time, but even profane history teaches that the sun has lighted and warmed us for three thousand years, and geology puts it beyond doubtthat this period must be extended to millions of years.”
The third hypothesis relates tocurrentsof electricity. We have no knowledge of currents of electricity which could produce, however multiplied or intensified, such light and heat as are constantly poured forth from the sun into all space. That electricity is the intermediate cause of our sun’s energy, and of all solar energy, it is the purpose of this work to demonstrate, but not electriccurrents, which find their attractiveness to theorists in the vague suggestion of which Professor Proctor speaks, referring to comets, in his article on “Cometic Mysteries,” “that perhapsthisis an electrical phenomenon; perhapsthat other featureis electrical, too; perhapsall or mostof the phenomena of comets depend on electricity.” But he adds, “It is so easy to make such suggestions, so difficult to obtain evidence in their favor having the slightest scientific value. Still, I hold the electrical idea to be well worth careful study. Whatever credit may hereafter be given to any electrical theory of comets will be solely and entirely due to those who may help to establish it upon a basis of sound evidence,—none whatever to the mere suggestion, which has been made time and again since it was first advanced by Fontanelle.” It will be seen that the present work, in demonstrating the true source and mode of solar energy, in itself presents a full and sufficient explanation of all the cometic mysteries referred to, as well as all those pertaining to other solar systems in space, and the multifariousphenomena which they present. Indeed, the philosophic mind will not be satisfied with the sufficiency of any hypothesis which will not unlock the mysteries and clearly explain the phenomena of other systems,—of comets, variable and temporary stars, double stars, and all the complicated celestial economy which to the eye of the mere observer presents a bewildering scene of the operation of independent and inscrutable forces. The fifth hypothesis cited, that of meteoric impact, doubtless plays a part, as we know from the generation of light and heat by the constant passage of similar bodies through our own atmosphere. And we know, of course, that the sun, by its vastly-increased attraction, must be subjected to the constant impact of such meteoric bodies in enormous numbers. But the fatal defect in the theory is that such impacts, to produce the radiant energy of the sun, must constantly add to its mass in like proportion, and as the motions and distances of the planets in their orbits are regulated and preserved by virtue of the substantially constant mass of the sun, any progressive and considerable increase in its mass must constantly bring the planets nearer and nearer, and thus increase their orbital velocity. Helmholtz quotes from Sir William Thomson’s investigation, that, “assuming it to hold, the mass of the sun should increase so rapidly that the consequences would have shown themselves in the accelerated motion of the planets. The entire loss of heat from the sun cannot, at all events, be produced in this way; at the most a portion, which, however,may not be inconsiderable.” R. Kalley Miller, in “The Romance of Astronomy,” says, “But more recent observations have led Sir William Thomson to a modification of his theory. He has calculated that if the meteoric shower were sufficiently heavy to make up for the sun’s whole expenditure of heat, the matter of the corona must be so dense as seriously to perturb the orbits of certain comets which pass very close to his surface,—a result which is found not to be the case. But the meteoric theory is only thrown back a step. If the sun’s mass were originally formed, as is not at all improbable, by the agglomeration of these particles, Sir William Thomson has calculated that the heat generated by their thus falling together would be sufficient to account for a supply of twenty million years of solar heat at the present rate of emission. And thus, though the meteors are not sufficient to maintain the energy of our system unimpaired, they may yet have been the original storehouse from which all that energy was derived …. But if the economy of our system be spared long enough, the day must come when the sun with age has become wan; when the matter of the corona has all been drawn in and used up without avail; when the lavish luxuriance with which he has showered abroad his light and heat has finally exhausted all his stores. He has still power, aided by the resisting medium, to drag his satellites one by one down upon his surface; and the shock of each successive impact will, for a brief period, give him a fresh tenure of life. When the earth crashes into thesun it will supply him with a store of heat for nearly a century, while Jupiter’s large mass will extend the period by nearly thirty thousand years. But when the last of the planets is swallowed up, the sun’s energies will rapidly die out and a deep and deathly gloom gather about nature’s grave. Looking into the ages of a future eternity, we can see nothing but a cold and burnt-out mass remaining of that glorious orb which went forth in the morning of time, joyful as a bridegroom from his chamber, and rejoicing as a strong man to run a race.”
The sixth hypothesis is that to which most credence is now given. It is that of evolution of energy by condensation of volume. Professor Proctor (“The Sun as a Perpetual Machine”) says, “In company with this great mystery of seeming waste comes the yet more difficult problem, how to explain the apparent continuance of solar light and heat during millions of years. We know from the results of geological research that the earth has been exposed to the action of the solar rays with their present activity during at least a hundred million years. Yet it is difficult to see how, on any hypothesis of the generation of solar heat, or by combining together all possible modes of heat generation, a supply for more than twenty millions of years in the past and a possible supply for as long a period in the future can be accounted for.” Of these vast periods of terrestrial existence in the past we quote the following from a recent publication:
“Professor C. D. Wolcott expresses the opinion that geologic time is not to be measured by hundreds of years, but simply by tens of millions. This is widely different from the conclusion arrived at by Sir Charles Lyell, who, basing his estimate on modifications of certain specimens of marine life, assigned 240,000,000 years as the required geological period; Darwin claimed 200,000,000 years; Crowell, about 72,000,000; Geike, from 73,000,000 upward; McGee, Upham, and other recent authorities claim from 100,000,000 up to 680,000,000.”
Helmholtz (“On the Origin of the Planetary System”) says, “It is probable rather that a great part of this heat, which was produced by condensation, began to radiate into space before this condensation was complete. But the heat which the sun could have previously developed by its condensation would have been sufficient to cover its present expenditure for not less than 22,000,000 of years of the past …. We may therefore assume with great probability that the sun will still continue in its condensation, even if it only attained the density of the earth, though it will probably become far denser in its interior, owing to its far greater pressure; this would develop fresh quantities of heat, which would be sufficient to maintain for an additional 17,000,000 of years the same intensity of sunshine as that which is now the source of all terrestrial life.” Of this process of condensation Professor Ball, in his recent work, “In the High Heavens,” says, “It goes without saying that the welfare of the human race is necessarilyconnected with the continuance of the sun’s beneficent action. We have indeed shown that the few other direct or indirect sources of heat which might conceivably be relied upon are in the very nature of things devoid of necessary permanence. It becomes, therefore, of the utmost interest to inquire whether the sun’s heat can be calculated on indefinitely. Here is indeed a subject which is literally of the most vital importance, so far as organic life is concerned. If the sun shall ever cease to shine, then it must be certain that there is a term beyond which human existence, or indeed organic existence of any type whatever, cannot any longer endure on the earth. We may say once for all that the sun contains just a certain number of units of heat, actual or potential, and that he is at the present moment shedding that heat around with the most appalling extravagance.” Quoting from Professor Langley, he says, “We feel certain that the incessant radiation from the sun must be producing a profound effect on its stores of energy. The only way of reconciling this with the total absence of evidence of the expected changes is to be found in the supposition that such is the mighty mass of the sun, such the prodigious supply of heat or what is the equivalent of heat which it contains, that the grand transformation through which it is passing proceeds at a rate so slow that, during the ages accessible to our observations, the results achieved have been imperceptible …. We cannot, however, attribute to the sun any miraculous power of generating heat. That great body cannot disobeythose laws which we have learned from experiments in our laboratories. Of course no one now doubts that the great law of the conservation of energy holds good. We do not in the least believe that because the sun’s heat is radiated away in such profusion it is therefore entirely lost. It travels off, no doubt, to the depths of space, andas to what may become of it there we have no information. Everything we know points to the law that energy is as indestructible as matter itself. The heat scattered from the sun exists at least asethereal vibration, if in no other form. But it is most assuredly true that this energy, so copiously dispensed, is lost to our solar system. There is no form in which it is returned, or in which it can be returned. The energy of the system is as surely declining as the store of energy of the clock declines according as the weight runs down. In the clock, however, the energy is restored by winding up the weight, but there is no analogous process known in our system.” The purpose of the present work, however, is to clearly demonstrate that just such a process is actually being carried on, and has been so carried on from the beginning, and will be forever. This writer continues reviewing the suppositions formerly entertained, that the sun was a heated body gradually cooling down, or that it was undergoing absolute combustion, and shows that they were utterly insufficient. He then refers to the theory of meteoric supply, of which he says, “It can, however, be shown that there are not enough meteors in existence to supply a sufficient quantity of heatto the sun to compensate the loss by radiation. The indraught of meteoric matter may, indeed, certainly tend in some small degree to retard the ultimate cooling of the great luminary, but its effect is so small that we can quite afford to overlook it from the point of view that we are taking in these pages. It is to Helmholtz we are indebted for the true solution of the long-vexed problem. He has demonstrated in the clearest manner where the source of the sun’s heat lies …. A gaseous globe like the sun, when it parts with its heat, observes laws of a very different type from those which a cooling solid follows. As the heat disappears by radiation the body contracts; the gaseous object, however, decreases in general much more than a solid body would do for the same loss of heat …. The globe of gas unquestionably radiates heat and loses it, and the globe, in consequence of that loss, shrinks to a smaller size …. In the facts just mentioned we have an explanation of the sustained heat of the sun. Of course we cannot assume that in our calculations the sun is to be treated as if it were gaseous throughout its entire mass, but it approximates so largely to the gaseous state in the greater part of its bulk that we can feel no hesitation in adopting the belief that the true cause has been found.”
Regarding the constitution of the sun, it may be stated, however, that we only see its photosphere, which is the visible sun, and the whole volume has a density about that of water; but no man has ever seen the body of the sun itself. In this respect it is like the planet Jupiter: we only know that itsdensity cannot be less than one-fourth the density of the earth’s solid globe. If the photosphere extend to a depth of one thousand, ten thousand, or a hundred thousand miles, the density of the sun’s body or core will be correspondingly increased. Even computing the whole visible volume, the density is far greater than that of any gas we know, even with the solar pressure of gravity; with the sun’s metallic vapors, if the whole core were already vaporized, we would not, to say the least, be likely to observe the sun-spots and other solar phenomena as we find them actually to occur; this, however, will be more fully considered later on. The author continues, “But there is a boundary to the prospect of the continuance of the sun’s radiation. Of course, as the loss of heat goes on the gaseous parts will turn into liquids, and as the process is still further protracted the liquids will transform into solids. Thus, we look forward to a time when the radiation of the sun can be no longer carried on in conformity with the laws which dictate the loss of heat from a gaseous body. When this state is reached the sun may, no doubt, be an incandescent solid with a brilliance as great as is compatible with that condition, but the further loss of heat will then involve loss of temperature …. There seems no escape from the conclusion that the continuous loss of solar heat must still go on, so that the sun will pass through the various stages of brilliant incandescence, of glowing redness, of dull redness, until it ultimately becomes a dark and non-luminous star …. There is thus a distinctlimit to man’s existence on the earth, dictated by the ultimate exhaustion of the sun …. The utmost amount of heat that it would ever have been possible for the sun to contain would, according to this authority (Professor Langley), supply its radiation for eighteen million years at the present rate …. It seems that the sun has already dissipated about four-fifths of the energy with which it may have originally been endowed. At all events, it seems that, radiating energy at its present rate, the sun may hold out for four million years or for five million years, but not for ten million years …. We have seen that it does not seem possible for any other source of heat to be available for replenishing the waning stores of the luminary.” He concludes by saying that the original heat may have been imparted as the result of some great collision, the solar body having itself been dark before the collision occurred, and that it may be reinvigorated by a repetition of a similar startling process, but indicates in general terms that such an operation would be bad for the round world and all contained therein. It would, in fact, be rough treatment for even a hopeless case.
Condensation of the solar volume is unquestionably a source of heat, for we know that the solid or liquid interior of the earth increases in temperature at a definite ratio as we descend through its crust; but long before the sun shall have become contracted to the density of the earth all its heat will have become substantially internal heat, and it can then supply no more by radiation to its surrounding planets.
It will be seen that the radiant energy of the sun on any of the above hypotheses is not sufficient to account even for the life period of the earth in the past, and that its future period of energy must be still more brief. Professor Ball (“In the High Heavens”), basing his views on Laplace’s “Nebular Hypothesis,” says, “Looking back into the remote ages, we thus see that the sun was larger and larger the further back we project our view. If we go sufficiently far back, we seem to come to a time when the sun, in a more or less completely gaseous state, filled up the surrounding space out to the orbit of Mercury, or, earlier still, out to the orbit of the remotest planet.” According to this hypothesis, all these brilliant suns, the author says, will “settle down into dark bodies like the earth,” and that “every analogy would teach us that the dark and non-luminous bodies in the universe are far more numerous than the brilliant suns. We can never see the dark objects; we can discern their presence only indirectly. All the stars that we can see are merely those bodies which at this epoch of their career happen for the time to be so highly heated as to be luminous …. It may happen that there are dark bodies in the vicinity of some of the bright stars to which these stars act as illuminants, just in the same way as the sun disperses light to the planets.” One would naturally suppose, however, that there must be some sort of laws to govern such stupendous operations, and that nature is not merely engaged in blowing bubbles. To quote Professor Newcomb:“At the present time we can only say that the nebular hypothesis is indicated by the general tendencies of the laws of nature; that it has not been proved to be inconsistent with any fact; that it isalmost a necessary consequence of the only theory by which we can account for the origin and conservation of the sun’s heat; but that it rests on the assumption that this conservation is to be explained by the laws of nature as we now see them in operation. Should any one be sceptical as to the sufficiency of these laws to account for the present state of things, science can furnish no evidence strong enough to overthrow his doubts until the sun shall be found growing smaller by actual measurement, or the nebulæ be actually seen to condense into stars and systems.”
While the validity of the views set forth in the present volume does not depend on the sufficiency or insufficiency of the nebular hypothesis, and in fact requires the condensation as well as the expansion of the solar volumeunder the influence of heatto be recognized and its extreme importance pointed out, yet it must not be supposed that this great generalization of Kant and Laplace, based on the views presented originally by Sir William Herschel, is established, or that the difficulties in its way are not so enormous as to be almost insuperable. Professor Ball points out that thousands of bodies occupy our solar system, and together compose it as a whole; that these have orbits of every sort of eccentricity and direction, and occupying all possible planes which can pass through the sun;that the bodies circle around the sun, some backward and others forward, and that only the planets seem to conform to some common order; and without this order, which may be accidental, so far as our knowledge goes, the system would have been disrupted long since, if it ever could have begun its operations; and that in this view the heavens may be strewn with wrecks of systems which failed to survive from inherent want of harmony,—that is to say, as based on observation only. Whether the nebular hypothesis be a universal or a partial law of development, or whether the real processes be quite different, cannot, however, depend on the continued maintenance and evolution of the sun’s energy, as this source must in truth be sought for in quite a different direction.
The remaining hypothesis (the seventh) is considered in detail in Professor Proctor’s work, “Mysteries of Time and Space.” The fatal defect in Dr. Siemens’s theory is, that his gases will not be projected from the sun’s equator. Professor Proctor says, “Thus the centripetal tendency of matter at the sun’s equator is very much greater (many hundreds of times greater) than its centrifugal tendency, and there is not the slightest possibility of matter being projected into space from the sun’s surface by centrifugal tendency. Nor is there any part of the sun’s mass where the centrifugal tendency is greater than at the surface near the equator. So that, whatever else the sun may be doing to utilize his mighty energies, he is certainly not throwing off matter constantly from hisequatorial regions, as Dr. Siemens’s theory requires.” There are other difficulties which Professor Proctor considers, such as the doubt as to the power of the sun’s rays to disassociate combined gases in space, and also that, since both light and heat must be utilized in this work, if the sun’s energies are to be perpetually renewed, these forces would sensibly disappear in work, and the result would be that the fixed stars would be invisible beyond their domains, and their light, when not totally cut off, would be greatly diminished, in any event, as distances increased, which is not the case. Besides, these gases thus disassociated could never be entirely used by the sun, and the remainder would be wasted, and the part wasted would vastly exceed that utilized, probably in as great proportion of waste as that of the sun’s light not utilized by the planets, which gather but one two-hundred-and-thirty-two-millionths of the whole. It may be further added that these gases would be mechanically mixed, the combined and the disassociated, and this would be mostly the case in those parts nearest the sun, so that large volumes of spent and useless gases would have to be carried in to no purpose whatever. In fact, these gases would gradually form a closed circuit of supply and discharge, and surrounding space would be but slightly affected. Professor Proctor concludes, “We have, in fact, the fallacy of perpetual motion in a modified form.”
It will be apparent that under any single one, or all, of these hypotheses, the future prospect for created forms and continued existence is hopeless,and that the inevitable result must do violence to every conception of either an intelligent creative power or the operations of universal law. The mind revolts from the continued degradation and destruction of all organic creation, while the malevolent and iconoclastic forces of nature hold high revel over final ruin and eternal destruction, brought about by their own incessant efforts, striking out blindly to make or mar, and they alone the deathless survivors, the half-blind fates and furies of the eternal future. It betokens, not the processes of orderly government, but the reign of anarchy.
Note.—Since this work has been in press, at the annual meeting of the British Association, August 8, 1894, Lord Salisbury, the President, delivered a powerful and lucid address on the present status of scientific knowledge and its limitations. With reference to the antiquity of the earth we quote the following: “It is evident, from the increase of heat as we descend into the earth, that the earth is cooling, and we know, by experiment within certain wide limits, the rate at which its substances—the matters of which it is constituted—are found to cool. It follows that we can approximately calculate how hot it was so many million years ago; but if at any time it was hotter at the surface by fifty degrees Fahrenheit than it is now, life would then have been impossible upon the planet, and, therefore, we can without much difficulty fix a date before which organic life on earth cannot have existed. Basing himself on these considerations, Lord Kelvin limited the period of organic life upon the earth to a hundred million years, and Professor Tait, in a still more penurious spirit, cut that hundred down to ten.” If a period of anything like ten million years, even, has been requisite to cool the earth’s surface only fifty degrees in temperature, what time must have elapsed since the terrestrial globe had a temperature high enough to effect the difficult chemical combinations of many of the elements which compose its structure? And even this must have been far less than the vast cycles of time during which original consolidation was effected. Through all these ages the sun must have been pouring out his radiant energy at at least his present rate. Radiation of heat from the earth may have been relatively less rapid from a denser carbon-laden atmosphere in times past than at present, but it never could have been more so. The whole address cited is, indeed, strongly corroborative of the facts upon which the present work is based.