408 WONDERS OF THE COMETS. miles in length. The comet of 1811 was of so vast a size that it was many times the bulk of the earth; and its luminous projection was 132,000,000 miles long. According to Lambert's calculation, however, that comet was seventeen times larger than Jupiter, and 25,100 times larger than the earth. Many comets have no nucleus, and the smallest stars are to be seen through them. In those with a nucleus, the light nebulosity is not in contact with the nucleus. In the comet of 1811 the nebulosity was 25,000 miles, and its interior surface was 30,000 miles from the centre of the nucleus. The tail is not to be distinguished from the nebulosity on its side. The nucleus of the comet of 1811 was 2,700 miles in diameter. Some are not 500 miles, and others not forty miles in diameter. The tail of the comet of 1680 was ninety degrees or 100,000,000 of miles long. That of 1769 was ninety-seven degrees and 42,000,000 of miles. One in 1744 had five or six tails millions of miles each in length. Hitherto no phases have been discovered in them. Hevelius and Dorfel first explained that the orbits of comets were parabolic with the sun in the centre. Newton connected the idea with his hypothesis of universal gravitation, and Halley taught that the orbits were periodical. In one instance this idea was partly verified, but the two last expected were not seen, though anxiously looked for by hundreds of observers. Since it appears that the sun and its system progress in space, they seem likely to be exterior planets of other systems, which become involved in the solar vortex, and are turned aside or back on reaching the plane of the sun's equatorial action. Hence they may be periodical in other systems, but subject to these deflexions. Most comets present some differences of phenomena which disturb previous theories regarding them. PRECISION OF CALCULATION. 409 Meteoric observations also reveal very extraordinary astronomical phenomena. The height of meteors as taken from the earth is from 20 to 120 miles, but the average is about 60 miles. The average weight of the meteoric stones discovered in 1866 was about two ounces, and they came at a velocity of from thirty to fifty miles per second. Their great brilliancy was produced by the violent friction that took place in their passage through the air. The velocity of the meteors in November, 1866, was 46 miles per second. The accuracy with which astronomers calculate the movements and results of our planetary system, the precise time of eclipses, and the arrival of comets, after wandering for hundreds of years, evinces wonderful triumphs of scientific achievements. But, as Herschel remarks, they are all exceeded by the accuracy of the calculations made by the tables of the Nautical Almanac on the "Sun's altitude", and "lunar distances", by which a navigator, with the aid of a little portable instrument, can tell, on the vast expansive ocean, the exact place upon the globe on which his ship floats. Some time since a captain of a ship who had been three months at sea without ever seeing one land-mark, and who had sailed at varying rates, drifted by different currents, and tacked in different directions over a distance of 8,000 miles of the trackless ocean, was on a certain morning enveloped in a fog. He ordered that the ship should heave to till the fog cleared away, as, said he, according to my calculations, our ship should now be within a few miles of the lighthouse of Rio de Janeiro. The ship hove to the fog cleared away-and the lighthouse was revealed on the precise relative position he indicated! We admire the stupendous résults attained by modern 410 STRUCTURE OF THE HEAVENS. science. Yet, to our souls, capable of such comprehensive conceptions, and of expanding to the lofty range of our gigantic intellectual powers, all these dwindle into contemptible insignificance, when contrasted with the ponderous moles of luminous worlds, the engineering talent, the potential energy, and complicated machinery displayed in the construction and movements of the heavenly bodies, beneath the expansive and lofty azure dome of the sky. See! they are whirling round each other at amazing distances and with inconceivable rapidity. Yet, we see not the centripetal cord that restrains them from flying off in the tangential direction! We see not the hook nor the chain that suspends them, and still we are not afraid their great weight will bring them down and crush us to annihilation! We know not where the mighty pillars of brass or of bronze were cast which support that dome, from which they are all suspended, or whether the foundations were laid on the crests of the eternal mountains. Oh! they require neither columns of brass nor of bronze, nor eternal mountains for foundations to support them. See! they are all pendulous and moving and floating in ether; they are dispersed over the south and over the north into empty space, aud are built upon no foundation but the mere will and the word of the wise Fabricator and the Almighty Architect, and yet they are poised with greater stability than if built upon quarries of adamant! "He stretcheth out the north over the empty space, and hangeth the earth upon nothing"-Job, xxvi. 7. My soul! thy everlasting inheritances, thy hopes of a blessed immortality, are built upon the promises and on the same word of "Him who has all power in heaven and on earth". The same right arm which sets agoing and directs that celestial machinery, is stretched out to guide and to shield me, CONFIDE IN THE MIGHTY ARCHITECT! 411 his heir of salvation. "Then why are you fearful, O you of little faith?" At his word these thousands of worlds emerge out of nothing is his arm shortened? No. Have confidence: "Fear not, for I am with thee: the right hand of my Just One hath upheld thee”Isaias, xli. 10. Though hitherto you have slept in tepidity, and have moved slowly in the way of perfection, he will accelerate your motion: though grace has shone but languidly in your soul, as a scintillating spark, "yet, many waters cannot quench it, nor all floods drown it". Though the fire of charity have burned in your heart but feebly, as a smouldering flame in smoking flax, fervently supplicate Him the true light, and He will supply new wick, and pour in a copious supply of oil of holy unction, and you will be hung up as a brightly burning lamp in the palace of eternal glory. Fear not the difficulties which surround you, and the intricate, eccentric mazes in which you are involved in your journey towards heaven, seeing how God directs with unerring precision the intricate evolutions of all the planets in their orbits and seemingly irregular mazes. "Mazes intricate, Eccentric, intervolv'd; yet regular, Vision cannot convey us even to the suburbs of the metropolis of that region of stars; but God is above them, and they give us a security and afford us an idea of the glory that is to come in the city of Sion. Why are you fearful? "Since the great Sovereign sends Ten thousand worlds, To tell us He resides above them all, In glory's inapproachable recess". 412 ARGUMENTS OF OMNIPOTENCE. These amazing structures, moulded in the palms of God's hands, and floating in fluid ether through the provinces of Jehovah's realms, beaming with effulgence, and perhaps teeming with vitality, are all luxuriant exhibitions of the creative power of the Omnipotent. But, as arguments of Omnipotence, they dwindle into despicable insignificance, and weigh not even as the down of a feather, when contrasted with those drawn from the soul and its faculties, this treasure and wonder of intellectuality and immortality which each of us carries in his bosom. Neither should the crush of worlds or the wreck of matter or the extinction of all those luminous orbs suspended from the etherial azure vault, or roaming through limitless plains, be estimated as the value of a grain of sand when compared with the loss of one soul, created for God and the happiness of a blessed immortality. "Not all yon luminaries quench'd at once, Which gropes for happiness, and finds despair". All these dazzling luminaries and rolling worlds reflect but a spark of the Deity's magnificence, and spell but a syllable of Jehovah's name; yet they supply us with an idea of his Almighty power, and inspire us with confidence in his eternal promises, and of one day grasping the things we hope for "for heaven and earth shall pass away, but his word will not pass away": and if his promises were not fulfilled, then, indeed, we might well doubt the existence and materiality of the planets themselves. "If these fail, The pillar'd firmament is rottenness, |