imagined the firmament a solid sphere, with a number of tapers whirled round the earth, we should be apt to think that the Creator of the world was a limited being; but when we contemplate the vast amplitude of planetary systems, and the immense spaces by which they are separated from each other, we behold plans and operations which are in perfect unison with the immensity of his nature, with his boundless power, his uncontrollable agency, and his universal presence. Wherever we turn our eyes throughout the scene of nature, and fix our attention on its plans and movements, we uniformly find the Creator acting like himself; and in no case is this more strikingly displayed than in the grandeur and magnificence of the orbs of heaven, and the immense spaces with which they are surrounded.

This is likewise the representation which the Scriptures give us of the immensity and incomprehensible nature of the Deity. "Great is Jehovah and of great power; his understanding is infinite; his greatness is unsearchable." He is not only "high above all nations," but "his glory is above the heavens." "He dwelleth on high, and humbleth himself to behold the things" not only that are "on the earth," but even "the things that are in the heavens." Vast as the celestial spaces are, "he meted out heaven with the span," and "stretched forth the heavens alone." "Among the gods there is none like unto thee, neither are there any works like unto thy works." "Canst thou by searching find out God? Canst thou find out the Almighty to perfection? Who can utter the mighty operations of Jehovah? Who can show forth all his praise? Lo, these are but parts of his ways; but the thunder of his power, or the full extent of his omnipotence, who can comprehend?" In relation to a Being who is thus described, we can expect nothing but what is wonderful, and incomprehensible by finite minds. The declarations of inspired men bear testimony to the discoveries of astronomy as in perfect unison with the attributes of the Divinity, so that science and revelation completely harmonize in the views they unfold of the plans and arrangements of the Deity, and of the immense spaces which intervene among the systems of the universe.

Whether man will ever be permitted to traverse any of the vast spaces of the universe to which we have now adverted, is a question which is at present beyond our province to re

solve. In our present state of corporeal organization, it is impossible to wing our flight even to the nearest celestial orb in that system of which we form a part, much less to the distant starry regions. How pure spirits, disconnected with material vehicles, may transport themselves from one region of creation to another, it is impossible for us, in the present state, to form a conception. But it is possible to conceive of a system of organization far more refined than the present, and susceptible of a power of motion far surpassing what we have an opportunity of witnessing in this terrestrial sphere; a locomotive power, which might enable an intelligent agent to keep pace with the rapid motions of the celestial orbs. We have only to suppose organical vehicles, constructed with matter far more subtle and refined than hydrogen gas or the ethereal fluid, and approximating to the tenacity of light itself. As we find animalculæ many thousands of times less than the least visible point, their bodies must be constructed of materials extremely subtile and refined; and hence we may infer that the same All-wise Intelligence, who formed such minute and refined structures, can with equal ease construct a material organization for the residence of a rational soul out of the finest materials which creation can supply, and endow it with a capacity of rapid motion superior to that of some of the celestial globes which roll around us. It is not improbable that angelic beings are connected with such a system of material organization, which enables them to move with rapidity from one part of creation to another; and it is possible that man, in a future world, may be invested with such vehicles and such powers of rapid motion. At the same time, even with such locomotive powers, only a small portion of the universe could be supposed to be visited or explored, even after a lapse of ages. It is highly probable that, at this moment, there is not a single subordinate intelligence, even of the highest order of created beings, who is acquainted with every region of universal nature and the objects it contains, and that the greater part of the vast universe, with its scenery, movements, and inhabitants, is known only by Him who formed it by his power and fills it with his presence.

CHAPTER V.

ON THE MAGNITUDE OF THE STARS.

In our attempts to ascertain the magnitudes of any of the heavenly bodies, we must first endeavour to determine the distances at which they are placed from our abode; and, in the next place, we must measure, as accurately as possible, the apparent diameters of the bodies whose magnitude we wish to determine. The extreme difficulty of determining these two points, in certain instances, on account of the smallness of the angles which require to be measured, has hitherto prevented us from ascertaining with precision the real magnitudes of the bodies connected with the sidereal heavens. We formerly were led to conclude, on good grounds, that their distances were almost immeasurably great, and, consequently, that, as they emit a certain degree of splendour to our eye, even from such remote distances, their bulk must be immensely great. But no precise conceptions could be formed as to this point so long as the annual parallax of some of the stars remained undetermined.

The annual parallax of the star 61 Cygni being now in all probability ascertained (as stated in the preceding chapter), we are in possession of cartain data which may lead to the determination of the real magnitude of that body. But a difficulty still remains. The stars are found to have no sensible diameters. When viewed through telescopes of the greatest power, they present no visible disks or well-defined surfaces to the eye, as the planets do when viewed through such instruments, but appear only as so many shining and undefined points. When they are viewed through a telescope of moderate size, their diameters appear less than when examined by the naked eye, but considerably more brilliant. When we view them with a telescope of great power, the apparent diameters will be somewhat increased, but not according to any regular proportion, as happens in the case of the planets; and even when seen with the same power, through different telescopes, their apparent magnitudes are

not precisely the same. Sir William Herschel, who viewed these bodies under almost every aspect, uniformly found that their diameter was less in proportion as the higher powers were applied; and the smallest proportional diameter he ever obtained was when he employed the extraordinary power of 6450 times. From such observations it appears that the apparent diameters of the fixed stars do not arise from any sensible disk, but from other causes with which we are not acquainted. Dr. Halley remarks that "the diameters of Spica Virginis and Aldebaran (two stars of the first magnitude) are so small, that when they happen to immerge behind the dark edge of the moon, they are so far from losing their light gradually, as they must do if they were of any sensible magnitude, that they vanish at once with all their lustre, and emerge likewise in a moment, not small at first, but at once appear with their full light, even although the emersion happen when very near the cusp, where, if they were four seconds in diameter, they would be many seconds of time in getting entirely separated from the limb. But the contrary appears to all those who have observed the occultations of those bright stars." Every one who has been in the habit of viewing the starry firmament with good telescopes will at once admit that, although that instrument brings to view numerous stars which the unassisted sight cannot perceive, yet they appear only as luminous points with no well-defined sensible diameters, although their light is much more brilliant than to the naked eye.

Hence the difficulty of determining, with precision, the real magnitudes of any of the fixed stars. From their immense distance we are perfectly certain that they are bodies of immense size, otherwise they would be altogether invisible from our terrestrial sphere, or from any part of the solar system. But we have hitherto obtained no sufficient data for estimating their exact size, as we have done in relation to the globes which compose the planetary system. Since, then, the apparent diameters of the stars, even those of the first magnitude, are so small as not to amount to a single second, we cannot hope, in the mean time, to determine their measure with any degree of certainty. We may assign them a measure which we certainly know they do not exceed, but we cannot be sure that that measure is not too great. All luminous objects appear larger than those of the same dimensions which are opaque. The planet Mercury, when in its greatest

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brightness, appears larger than when it is seen to pass, like a dark spot, across the disk of the sun, although it is nearest the earth in this last position. The apparent diameters of the fixed stars are much smaller than they have generally been supposed by those who have attempted to measure them. Yet, small as they are, their real magnitudes must be very great, since they are visible to our sight at the immense dis-. tance at which they are placed. In proportion to the greatness of their distance and the smallness of their apparent diameters will be their real magnitudes. If we suppose the apparent diameters of any of the stars observed by Dr. Bradley to be equal to the 400,000th part of the sun's apparent diameter, or 1-200th of a second-which is a probable supposition for a star of the second magnitude-it will follow that such a star is equal to the sun in magnitude. For, if the sun were removed to the distance at which such a star is situated, he would appear no larger than those twinkling points, nay, would perhaps disappear altogether from our view. From all the observations and reasonings that have been entered into on this subject, we have no proofs that any of the stars are less than the sun, but it is more probable that many of them equal and even far surpass that luminary in their real dimensions and splendour. Having obtained the parallax of 61 Cygni,* if we could find the exact apparent diameter of that star, its real bulk could be calculated with as much ease and certainty as the bulk of the sun, or moon, or any of the planets. But as this important element in the calculation is still a desideratum, we must resort to other methods by which we may arrive at the nearest approximation to the truth.

I have already alluded to the photometrical experiments of Dr. Wollaston, in relation to the comparative quantity of light emitted to our eye from the star Sirius and from the sun. In reference to these experiments, Sir John Herschel, in a marginal note, remarks: "Dr. Wollaston assuming, as we think he is perfectly justified in doing, a much lower limit of possible parallax in Sirius than we have adopted in the text, has con

This star belongs to the constellation Cygnus, or the Swan. Its right ascension for January 1, 1839, was 20h 59 41", and its declination 37° 57′ 42′′ north. In places 52° of N. latitude, this star passes the meridian within two or three minutes of the zenith. It is a star of about the fifth magnitude. It is 28 degrees nearly due east from the bright star Vega, or a Lyræ, in the constellation of the Harp, and nearly nine degrees south by east of Deneb, or a Cygni, the principal star in the Swan.