others, (as expressly,) the impossibility of any (other) motion in the earth than that terrible and penal motion of His shaking it that made it; others, that it cannot be moved totally in his place, nor be removed universal out of his place. So that, were it nothing else but the veneration and firm belief of that word of His, which the penmen thereof spake not of themselves, but by inspiration of the Holy Ghost, they that profess Christianity should not dare, much less adventure, to call the letter thereof in question concerning things so plainly, frequently, constantly delivered; should tremble at that curse which is denounced against those that add any thing unto it, or diminish any tittle of it; should fear to raise such a hellish suspicion in vulgar minds, as the Romish Church, by undervaluing the majesty and authority thereof, has done; should be affrighted to follow that audacious and pernicious suggestion which Satan used, and thereby undid us all in our first parents, that God had a double meaning in His commands, in effect condemning God of amphibology. And all this boldness and overweening having no other ground but a seeming argument of some phenomena, forsooth, which, notwithstanding, we know the learned Tycho, ¿'Аσтρоvоμáρxwv, who lived (fifty-two) years since Copernicus, has, by admirable and matchless instruments, and many years' exact observations, proved to be not better than a dream."

Let us see in what the Copernican and Tychonic systems consisted. We shall thereby discover that the Dean was somewhat hasty in his declaration that the Dane had overcome the Pole.

According to the modestly called "hypothesis" of Copernicus, the Sun is placed very near the centre of gravity of the whole system, and in the focus common to all the planetary orbits. Mercury and Venus perform their revolutions the nearest to the Sun; and next to these succeeds the Earth, with her satellite, perfecting their joint course, and in their revolution measuring out the annual period. Mars is the first of the superior planets next the Earth, and Jupiter and Saturn are in the wide space beyond. The constituent parts of the solar system are made up of these and the comets. The discoveries of later times have only proved a greater magnitude of system, and confirmed the truth of the hypothesis. That it should be received as Copernicus gave it, was only a logical result. It was simple, and agreeable to nature. The double motion of the Earth at once resolved all the phenomena of the heavens, to explain which had plunged all previous astronomers into perplexity, and made a confused theory tenfold more confusing. The acceptors of the hypothesis argued truly, that it was more rational to believe that the Earth moved round the Sun, than that the stupendous whole-planets, Sun, and firmament of stars-revolved around the inconsiderable Earth once

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in twenty-four hours. The supposition was harmonious, and the harmony confirmed the hypothesis; as, for instance, “that the motions of all the planets, both primary and secondary, are governed and regulated by one and the same law, which is, that the squares of the periodical times of the primary planets are to each other as the cubes of their distances from the Sun; and, likewise, the squares of the periodical distances of the secondaries of any primary, are to each other as the cubes of their distances from that primary." In the Copernican system, the Moon is a secondary of the Earth; in the older hypotheses it is a primary. In the latter case, the rule established by Copernicus could not be made to apply, because the periodical time, considered as that of a primary one, would not agree therewith.

Whiston's reason for accepting the Copernican proof of the motion of the Earth, is as simple as it is conclusive. He says, if the Earth does not move round the Sun, the Sun must move, with the Moon, round the Earth. "Now the distance of the Sun, to that of the Moon, being as 10,000 to 46, and the Moon's period being less than 28 days, the Sun's period would be found no less than 242 years, whereas, in fact, it is but one year."

It was seen that the Sun, as the great fountain of light and heat, ought to occupy the centre of a system; for, if the Earth were at that centre, and the Sun and planets revolving round it, the planets would then, like the comets, be scorched with heat when nearest the Sun, and frozen up in their aphelia. With the Sun in the centre, the law of gravity would account for his vast body attracting the planets, agreeably to the laws of circular motion and central forces. That such is the case, may not only be asserted, but demonstrated.

Mercury and Venus have two conjunctions with the Sun, but no opposition, proving that the orbits of these planets lie within that of the Earth. On the other hand, Mars, Jupiter, and Saturn have their conjunctions and oppositions to the Sun alternate and successive; which could not be, unless their orbits were exterior to the orbit of the Earth. The ascertained greatest elongations of Mercury and Venus from the Sun answer exactly to the distance at which Copernicus set them down in his system. In his disposition of the planets, which placed the latter at varying distances from the Earth, a variation in splendour and apparent diameter would ensue, of which all who gaze are conscious. The telescope, moreover, has proved the correctness of what Copernicus only guessed at, especially with reference to Venus, which is now new, now horned, then dichotomized, subsequently gibbous, afterwards full,-in short, increasing and diminishing her light, like the Moon, as Copernicus asserted she did, before he ever beheld the phenomena.

It is by the Copernican theory alone that reason can be given for the sometimes apparently direct, sometimes retrograde, motion

of the planets, and for their appearing at other times stationary. The same hypothesis accounted for many other appearances, to recount which would, perhaps, only weary our readers; but we may mention, finally, what was asserted by the acceptors of the theory; namely, that the times in which the conjunctions, oppositions, stations, and retrogradations of the planets were observed to take place, were not such as they would be, were the Earth at rest in its orbit; but precisely such as would happen, were the Earth to move, and all the planets, in the periods assigned them; and therefore," it was said, "this, and no other, can be the true system of the world."

But good Dean Wren insisted that Tycho Brahe had demonstrated the worthlessness of the Copernican theory. The Dean was over-hasty in such assertion. Tycho sought to establish an arrangement of the heavenly bodies, of an intermediate nature, between the Copernican and Ptolemaic systems. He took a little from each, rejected both, and failed in establishing his own. Tycho, it is true, could not reconcile himself to the motion of the Earth; but it is quite as true that he could not adopt the theory of Ptolemy. Tycho supposed the Earth to be fixed in the centre of a firmament of stars, and of the orbits of the Sun and Moon; but he imagined the Sun itself to be the central point of the planetary motions. This was rightly pronounced a monstrously absurd hypothesis; for it made the Sun, with all its planets, to revolve round the Earth once a year, thereby solving the phenomena arising from the annual motion; while those of the diurnal motion were accounted for by making the same bodies move round the Earth once also in twenty-four hours. Subsequently, the poor Earth was permitted to have a motion about its axis, in order to account for the diurnal phenomena; but this semi-Tychonic system was encumbered with such contradictions and mazes of conjecture, that it has been rejected alike by mathematicians and philosophers.

With regard to the Dean's allusion to Scripture, the reader may choose between Shuckford and Bishop Watson, for a satisfactory reply. The former remarks that Joshua recorded the miracle according to the knowledge then possessed by the people. The same writer adds, that if God had directed him to record the event in a manner more agreeable to true Astronomy, He must also have inspired the people with a true knowledge of the science. Bishop Watson, when commenting on the same event, more satisfactorily observes: "I think it idle, if not impious, to undertake to explain how the miracle was performed; but one who is not able to explain the mode of doing a thing, argues ill, if he thence infers that the thing was not done. The machine of the universe is in the hand of God: He can stop the motion of any part, or of the whole, with less trouble, and less

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danger of injuring it, than any of us can stop a watch." This is a great truth delivered in very indifferent English.

The system has stood and will stand. It has survived the opposition of Descartes, and has been confirmed by the "Principia" of Newton,-a work of which the most accomplished philosophers among the Jesuits were accustomed to allow, that it was mathematically true, although it was ecclesiastically in error! Upon the system of Descartes it is hardly worth while to pause; and yet some mention of it may be necessary. Briefly, then, Descartes imagined that the heavenly bodies completed their motions in a confused variety of vortices or whirlpools; the whole being carried round the sun in a vortex of ethereal matter, and each planet having a vortex of its own, in which its satellites were whirled on to accomplish their revolution round their particular planet. It has been truly observed that the irregular motions of the planets cannot be accounted for by their vortices, and that the supposition of an ethereal matter to perform the operation is without any foundation or analogy in nature.

But though this system, advanced by Descartes, is opposed alike by philosophers and divines, yet there must be allowed for the founder what is claimed for him by his admirers, namely, that, "by introducing geometry into physics, and accounting for the natural phenomena by the laws of mechanics, he did infinite service to philosophy, in purging it from that venerable rust which, in a long succession of ages, it had contracted."

And now, let us hear what Copernicus had to say on his own account. We can only give the substance of his reasons for rejecting the ancient system, which are as follows:-The motions of the sun and moon, according to the hypothesis of the ancients, were indicated with so little precision, that it was impossible to settle the unvarying length of the year. On the other hand, they had recourse to different principles, in order to explain the revolutions of the celestial bodies. At one time, he says, they admit ex-centric circles; at others, epicycles, the application of which does not agree with the ensemble of the system. They have no fixed basis. The most important problem, the form of the world, and the symmetry of the celestial bodies, they could neither invent nor demonstrate. He compares their system to a monstrous shape made up of members belonging to different bodies. His soul, he says, was afflicted, that no one had yet established an explanatory theory, showing the certain motion and the interpretation of the sidereal mechanism,—a theory, in short, worthy of the Divine Author of the system. After touching upon the earth's motion and the immovability of the sun, he adds: "On observing the motion of the planets, in reference to that of the earth, not only do we meet a perfect analogy and concordance, but we find, in the totality of the celestial bodies, order and symmetry. The entire universe forms

a harmonious whole, the parts of which are so well united with each other, that no one can be displaced without disorder and confusion falling on the rest. I feel convinced that learned and profound mathematicians will applaud my researches, if, as becomes true philosophers, they examine thoroughly the proofs which I bring forward in this work. If shallow or ignorant men feel inclined to misapply some passages of Scripture, perverting the sense, I would not pause; I despise beforehand their rash attacks. Lactantius even was a celebrated man, though a weak mathematician; and did not he wish to cast ridicule on those who believed in the spherical form of the globe? It is not, therefore, astonishing, that I should be rendered subject to the same censure. Mathematical truths are addressed only to mathematicians. If my opinions do not deceive me, my labours will not be without their utility for the Church, the helm of which is now in the hands of your Holiness." The Church, however, was affrighted at the wide liberty of thought in which men were now indulging; and it could no more patronize the sidereal reform of Copernicus, than it could sanction the ecclesiastical reform of Luther. The earth was the centre of the solar system, and upon it was reared the throne from which the Church claimed the obedience of the world. But here were two men, one of whom asserted that the Church had no such claim; and the other, that there was no earth there where Rome had built her throne. Between the two she was spiritually and materially annihilated, and she settled with the respective philosophers by cursing both.

His

When Copernicus received the printed copy of his book, he was stretched on a sick bed, worn down with years, labours, terrible anguish, and extreme infirmity. His mighty intellect had all but fled; his consciousness, however, remained. eye fell upon the volume, and it seemed to burn with new fervour as it rested on the book. His hand touched the completed work, felt it all over, gently, caressingly, passed over it here and there; and then he put it aside, well satisfied with what he had done for man, to seek pardon for his shortcomings in the sight of God. He died calmly on the 25th of May, 1543, at the age of seventy-three. His death was unmarked by the world generally: a circle of friends and scholars, who recognised the majesty of his intellect, and loved him for his individual worth, alone honoured the memory of the man whose decease they deplored. The hour of his great fame, and the season for statues, had not yet arrived. A humble stone, over his grave among the Canons of Warmia, bore an inscription worthy of the unpretending man. "I ask not," it said, "for the grace accorded to Paul, nor demand that which was given to Peter. I only implore the pardon which Thou didst not refuse to the thief on the cross." Thirty years after, the then