Several objections, made to the Theory of Concentric Spheres, answered, particularly the one that it contravenes religious opinions; demonstrating that the earth, and the other orbs of the universe, are formed on the best possible plan for the maintenance and support of organic life.

Some of the most prominent objections which I have heard advanced against the theory of concentric spheres are the following:

1st. That if the earth be not a solid globe, but a hollow concentric sphere, the quantity of matter being diminished, the attraction of gravitation must be lessened so much that all moveable bodies resting on the earth would be thrown off by centrifugal force, in the line of a tangent from the surface of the sphere.

2d. That according to the established laws of gravity, a hollow sphere could not exist in nature: that matter would be gravitated to the centre, and particularly about the polar openings, so as to make it collapse.

3d. That if the orbs were hollow spheres, the mutual influence of the planets on each other would be so far destroyed, that they would cease to revolve in regular orbits.

4th. That the interior of the sphere can never receive the light and heat of the sun; is involved in perpetual darkness, and more suited to the infliction of punishment on perverse and rebellious spirits, than for the residence of beings, fitted and designed for the pursuit and enjoyment of happiness.

5th. And finally, the adherents of the new theory have been charged with atheism, deism, and such like epithets, as though they intended to overturn the works of God, and thwart the laws of nature.

1st. As to the first objection, I would enquire, has it yet been ascertained with mathematical certainty, in what exact proportion one particle of matter attracts another? And may there not be some law of nature with which we are not yet well acquainted? All the experiments, hitherto made on the attractive power of gravity, were made on the principle, and under the belief, that the earth is a solid globe; and consequently the deductions were drawn accordingly. Suppose the attraction of gravitation, inherent in matter, to be so much increased, that a hollow sphere would possess the same attractive power, as if it were a solid globe, would not all the results and consequences be exactly the same? This being the case,—and I know no reason why we should conclude differently,—the whole force of the objection appears to fall to the ground. According to Newton's principle of gravity, the matter of the sphere would attract all particles of matter placed on the surface, as well upon the concave as convex, in nearly equal proportions; and the centrifugal force, which, on the outer side of the sphere, tends to throw bodies off, on the concave side, would have an opposite effect. Hence, a person standing, or trees growing, on the interior surface, would be in no more danger of being precipitated to the next sphere, between them and the centre, than those on the outer part of the sphere, when they should be turned (what is familiarly called) down.

The experiments made on the density of the globe, by observations with the plum-line, at the foot of a mountain, are very ingenious; but they must be subject to great uncertainty. The true deviation of the plum-line, the exact quantity of matter in the mountain, or, indeed, the quantity of matter between the plummet and the centre of gravity, are points difficult, if not impossible, to be ascertained with mathematical precision.

If the attraction of the sun is just sufficient to keep the earth in its orbit, what can give the tendency to retain Jupiter and Saturn in theirs, each of which, if solid, contains such a vast quantity more than the earth, and removed to so great a distance from the sun, that his influence upon either must be greatly lessened by both?

2d. As to the objections that a hollow sphere of the dimension of the earth cannot exist in nature, I can discover no sound reason to warrant such a conclusion. Many hollow cylinders and spherical figures, we know do exist on the surface of the earth; and notwithstanding their own gravity, which the different parts exert on each other, as well as the gravity of the earth, they retain their shape and position; and had the matter in the earth originally been thrown by a centrifugal force into the form of a hollow sphere, or had the first creating power originally given it that shape,—I can discover no good reason for a change; neither should I entertain any apprehensions of the particles of matter coalescing at the centre.

3d. The force of this objection I cannot appreciate; for if all the planetary orbs in the universe are composed of hollow concentric spheres, they must exert the same relative influence on each other, which they would if they were solid orbs, as they would each contain the same proportion of matter as respects each other. Hence no good reason appears why a system of hollow concentric spheres might not do just as well, and perform their revolutions with the same regularity, as a system of solid ones.

4th. This great and alarming objection comes next:—that we are about placing a world in eternal darkness, cut off from all the comforts and pleasures of refined life, for the enjoyment of which we are so eminently qualified. Let us examine the force of this objection; and if we cannot show that the interior is, at least in some degree, illuminated, we must then conclude that it is a very dreary abode, and unfitted for the residence of beings so fond of light as we profess to be.

According to the new theory, the northern polar opening is about four thousand one hundred and fifty miles in diameter, and the axis of the earth is at an angle of about twelve degrees with the axis of the plane of the polar opening; consequently, as the sphere revolves on its axis, one side of the verge of the polar opening will extend considerably further north than the other. The verge of the north polar opening on the low side, is laid down at about fifty degrees of latitude, and the verge of the high side at about sixty-eight degrees.

Now, supposing the sun to be exactly of the same diameter as the earth, and placed directly over the equator, when the low side of the verge was turned towards the sun, the direct rays from his northern limb, independent of refraction, would pass the edge of the lower part of the verge, and fall on the inner part of the sphere, on the concave part of the high side opposite, as far as eighteen degrees, or upwards. When the sun would be on the tropic of Cancer, in June, he must then throw the rays from his centre twenty-three and a half degrees further within the sphere, or within twenty-six and a half degrees of the equator; but the diameter of the sun being so much greater than the earth, the rays from his northern limb, would fall about thirty-three minutes further within the sphere, and leave not quite twenty-six degrees between that and the equator to be excluded from his direct rays. This relates to the northern polar opening; as to that of the south, which is believed to be much larger, we will make a few remarks. The lower side of the south polar opening, is laid in about latitude thirty-four degrees, and the higher side, in about latitude forty-six degrees. Were the sun of the same diameter with the earth, as above premised, and placed on the equator, his direct rays would be thrown into the south polar opening when the low side was towards him, about twelve degrees, or to within thirty-four degrees of the equator, and when on the tropic of Capricorn, in December, twenty-three and a half degrees further, that is, the inner part of the southern hemisphere of the sphere, on the high side, would be lighted thirty-five and a half degrees within the verge; and the direct rays of the sun would shine within ten and a half degrees of the inner centre of the sphere or equator. These observations, you will observe, are made in the most unfavourable point of view. It is well known, that the diameter of the sun, is vastly greater than that of the earth; consequently, his rays would pass into the polar opening so much further, in proportion as the angle of his diameter, and that of the earth, differ, which would be about thirty-three minutes further, bringing his direct rays in the south, within less than ten degrees of the equator; and this would be the case as the sphere revolved on its axis, once in every twenty-four hours. When the sphere turned, with its high side towards the sun, it would be night, or twilight, and when the low side was next the sun, it would be day; at all events, the direct rays of the sun would fall on a space of about thirty-six and a half degrees in breadth; the reflection from which would light the whole of the remaining portion of the inner part of the sphere, to a greater degree, than any moon-light with which we are acquainted. But there is another circumstance which tends to throw the rays of the sun much further into the concave than we have yet got them; that is, the refractive power of the atmosphere. It is a well known fact that the rays of light are very much refracted when passing out of a rare into a denser medium; and about the poles of the earth it is believed, (and this belief is confirmed by navigators) that refraction increases very considerably, owing to the great density of the atmosphere. We have good reason then to believe that refraction throws the rays of the sun several degrees further within the sphere. But let us take the known refraction of the horizontal ray, at or near the equator (say one half of a degree) it would throw the rays of light so much further into the concave, and not leave quite thirty-seven degrees in the centre of the sphere deprived of the sun's rays. The motion of the earth causes the apparent motion of the sun to be about fifteen degrees in an hour, as the diurnal revolution of the earth causes the sun to move apparently through three hundred and sixty degrees in twenty-four hours. Now it is a well known fact to all that the sun gives us light sufficient to be called day-light, for about an hour after he descends below the horizon; consequently he must afford us light when he is fifteen degrees obscured from our view. Accordingly, the sun, though he might not be visible, would illuminate the concave part of the sphere fifteen degrees further than his direct rays fall, which reduces the space in the interior of the sphere to the breadth of not quite seven degrees which would still remain unlighted.

But this is making calculations on the most unfavorable premises possible. Considering the form of the earth, and the power of refraction, I have no doubt but the direct rays of the sun would fall on every part of the inner sphere. However, I have proceeded on such premises as, I conclude, the most sceptical must admit. Light, we know, is reflected from solid bodies on which it falls, and also from the atmosphere: the rays of the sun, then, which would pass the lower part of the verge and fall on the opposite concave surface, would be reflected back in all directions, and most probably light the whole of the interior of the sphere sufficient for the ordinary purposes of life. By way of further illustration, suppose a perpendicular wall were raised on a plain, one mile high, does any person believe that there would be no light on the side of the wall opposite to the sun; although his rays would have to form an angle of one hundred and forty, or one hundred and fifty degrees, to reach the earth on that side of the wall? No axiom is more evident than that the rays of light are communicated to other places than those on which the rays of the sun fall directly; for example, we all know that a close room, however large, with a north window, will be sufficiently lighted by refraction and reflection from the atmosphere, provided there is no obstruction opposite the window, although the rays of the sun would have to form an angle of one hundred and fifty degrees to enter it, and why might not the whole interior of the sphere be lighted in the same manner, even supposing the rays of the sun should never enter directly. The north polar opening being about four thousand one hundred and fifty miles in diameter, and the southern six thousand three hundred and fifty, with the whole force of the direct rays of the sun falling on and passing through the atmosphere at either polar opening, it would not require refraction, or reflection, to make an angle of ninety degrees to light the whole of the interior concave; and certainly the polar openings are sufficiently large for the purpose, when we compare a common window with the dimensions of an ordinary sized room.

It is believed, by the adherents of the new theory, that the atmosphere, within the concave, and about the polar openings, is much denser than our atmosphere; which appears inevitably to be the case, as the centrifugal force on the convex has the tendency to throw the atmosphere from the surface, and on the concave to force it from the centre of motion, and nearer to the surface. This admitted, the rays of the sun passing out of a rare medium into a denser, would be refracted much further into the sphere; and the sun-shine on the surface of one sphere would be reflected obliquely, according to the angle of incidence, to the next sphere, and in this manner might be extended even beyond the centre of the concave. It is also believed, that near the verges of the polar openings, and perhaps in many other parts of the unfathomable ocean, the spheres are water quite through, (at least all except the mid-plane-spaces, or cavities) which being the case, light would probably be transmitted between the spheres.

The apparent elevation of celestial bodies above their true altitude, is greatest when the body is on the horizon, which is ascertained to be a little more than half a degree; hence, in our climate, the sun appears three minutes sooner, and sets three minutes later than is really the case, which increases the length of our day six minutes, by refraction. This gradually increases in proceeding from the equator to the frigid zones; and at the poles, were the earth entire, the day should become thirty-six hours longer, by refraction alone, than it would otherwise be.[38] It was doubtless owing to some peculiar refractive power in the northern regions, that caused the Dutch, who wintered on Nova-Zembla, (which is in latitude between seventy and seventy-eight degrees,) on the approach of summer, to see the sun about two weeks sooner than he should have appeared in that latitude, according to astronomical calculation.[39] This tends to show that there is more refraction in the northern regions than is observable in the south.[40]

From an attentive examination of these considerations, I am induced to conclude, that the interior of the sphere may be as well lighted as the exterior; or at all events, if not favoured with so great a degree of light at all times, it has a more regular and constant supply. But, admitting every thing on this subject that the opponents of the theory can suggest, I still discover no substantial reason why the earth may not be a hollow sphere. I can see no substantial reason why the inhabitants of that portion of the earth, (if any exist there) should be furnished with as great a degree of light, and as intense a heat, as we have upon the convex part of the sphere. Must it of necessity follow, that it cannot be inhabited, or if inhabited, that the beings who people its surface, are less happy than we? Certainly not. Is it not well known to us, that every grade and species of animals, under every variety of circumstance, whether inhabiting the air, the earth, or the water, are fitted by an all-wise Providence to their several conditions, and mediums, in which they reside? As well might we conclude, that the immense planet Jupiter, situated so far from the sun as he is, can be nothing but a dark, cold, and barren waste, unfitted for the residence of intelligent beings. It is ascertained by calculation, that the light and heat which Jupiter receives from the sun, is only the one twenty-seventh part of what the earth receives.[41] The light and heat which Saturn receives from the sun is estimated at only the one hundredth part of that of the earth;[42] and the planet Georgium Sidus, revolving such an immense distance further from the sun, than either of them, must enjoy still less light and heat; according to which, we would conclude, (if we adopt the belief, that the degree of light and heat, to which we are accustomed, is necessary for the support of life,) that those vast planets are not fitted by the God of nature for the residence of intelligent beings; however, I am inclined to believe that both light and heat are communicated to them, in some way not well known to us, sufficient for the purpose. The true principles of light and heat, and the manner in which they are generated and transmitted, are not perhaps yet well understood and defined.[43]

5th. Others, when the new theory is mentioned, cry Atheist, Deist, blasphemy! as if its advocates proposed to make a new world, and support it without the intervention of Divine Providence: such opponents scarcely deserve an answer. It is believed by all, that the earth, the sun, the moon and stars, are the work of an Almighty power. Whether solid globes or hollow spheres, they equally owe their existence to the great first cause, that spoke matter into existence, that arranged it in whatever form and order infinite wisdom dictated; and that still supports and governs the whole by universal and unvarying laws. But it is as well known, that the Almighty Disposer, interposes no miracles for the accomplishment of his designs, but makes use of means that are uniform in their application, to effect the intended purpose; hence Geologists, Philosophers, and Astronomers, attempt to account for the existence of all matter, and for the formation of planets, according to what is believed to be the established laws of matter. In so doing, we do not disparage the wisdom of the Creator, nor controvert the truth of that divine record, which Providence, in his goodness, has given us for our rule of life. True it is, the sacred scriptures give us very little information relative to the structure and formation of the earth and the other planets. They were not intended to teach mankind Geology, Geography, or Astronomy; yet where assertions are clearly and distinctly made respecting these things, we have reason to believe them literally correct: as for instance, when the Psalmist informs us, that God hung the earth upon nothing; that He balanced it in empty space, we are to look for corresponding facts; though it was at variance with the opinion of the world at that time, modern astronomy now teaches that such is the fact. In like manner, when we meet with assertions, such as that "the fountains of the great deep were broken up," (????? ???? ??? ????, chapter 1, verse 2,[44]) we must acknowledge their correctness; and I think it will be admitted, that they are at least as much in favour of this new theory as the old.

The skilful and attentive observer of nature, whether examining the most minute or the most sublime, will discover that infinite wisdom, judgment, and ingenuity, equally prevail throughout. The principal aims of the great author of all things, appear to have been animation, diversity, and usefulness; the air we breathe, the water we drink, the vegetables on which we feed; indeed every leaf and plant of the forest and field—all teem with animal life. Why then should we believe, or even presume to think, that the Almighty Fiat, which spoke matter into existence, for the support and maintenance of living creatures, innumerable, and endless in the variety of their organization, their colours, their passions, and their pursuits—why, I say, should we then presume, that the omnifick word would create even the smallest particle of any of the immense, the innumerable orbs in the universe, of inert or useless matter, devoid of activity and design? This earth, when compared with the magnitude and number of other planets we know, is but as a point; yet we can hardly conceive, small as she appears by comparison, that she was only designed to have animate life on her surface, and all the rest to remain useless! Such an idea seems unworthy of the Divine Being, whose essence is all perfection. Can we for a moment suppose, that the interior parts of the earth, have received less attention from the Creator, than the objects which are under our immediate inspection? On the contrary, may it not be more rationally inferred, that, for the object of more widely disseminating animation, spheres are formed within spheres, concentric with each other, each revolving on its own axis, and thus multiplying the habitable superfices?

Great and sublime as our conceptions of the Deity must be, when we contemplate the earth and its inhabitants—if we turn our attention to the solar system, our world dwindles into a little insignificant ball. Yet if we cast our eyes still beyond, and contemplate the eighty millions of fixed stars, which a good telescope brings to our view, each the centre of a mighty system of revolving worlds; and then reflect that all this is only one little dark corner of creation, we are lost in the magnitude of the contemplation. But when we come to consider each of these fixed stars, with their planets, and they with their satellites, all consisting of concentric spheres, revolving within each other, in due order, and adapted to the support and comforts of life, for countless millions of beings; we are struck with ten-fold astonishment and admiration, and bow with reverential awe, before Him who sits at the head of the universe, and governs the whole by unvarying laws. It would seem to me, that in contemplating this new order of creation, the imagination must break through and soar beyond its old boundaries. It would seem that on embracing this doctrine, the spirit must expand with increased devotion, and be entirely absorbed in the infinite wisdom and power of Him, who was competent to devise, and able to execute, such a beautiful arrangement of matter.