have impressed on our own globe the course which bringeth the regular return of its seasons, crowning the year with his goodness, who ordained this orbit, which might else by very many equally possible chances have deviated even into a comet's course, at once destructive of every creature that moves and every plant that blossoms, as they now exist. Another instance of the adjustment of forces, though by no means confined within such narrow limits as the former, may I think be observed in the so regulating the velocity of the rotation of each planet on its own axis, that the centrifugal force thence resulting, can never exceed such a proportion as leaves it still easily controlled by the gravitation arising from the mass of the same planet. For instance, in our own planet, the velocity of rotation is such as carries with it any body situated at the equator 1042 miles every hour, or rather more than a quarter of a mile in a second. But had this velocity been increased about twenty times, so as to produce a motion of five miles in a second, (the mass of the earth, and consequently its attraction of gravitation remaining the same,) we know that the centrifugal force thence resulting would be sufficient to detach any bodies which might be loosened, causing them to revolve like satellites ; -a gale of wind might thus carry off the roofs of our mansions and every thing which could be torn loose.

But the most beautiful extension of the doctrine of final causes has been disclosed by those extraordinary and elaborate researches, through which our theory of Physical Astronomy has received its full

development and perfection, and the mechanism of the heavens, as it has been appropriately termed, laid open to our admiring inspection. Now if we consider it, and consider it justly to be the grand triumph and noblest boast of man's reasoning powers, thus to have unravelled a portion of that universal mechanism,-how must we conceive of that intellect which planned, executed, and sustains the whole! of which the specimen visible and cognisable by us, forms probably but an infinitesimal fraction!-But to return. That great inventive mind which firmly laid the whole foundations of this sublime science, and in every respect pointed out to his successors the true methods of investigation to be pursued, still left his grand system in parts incomplete. It is truly wonderful indeed, that the transient life of one man (especially when it is remembered that from the probable exhaustion of an overworn mind he was compelled to suspend his researches at an age by no means advanced); it is wonderful, I say, that his span of intellectual energy should have sufficed to have accomplished one-half of what Newton did perform, rather than surprising that he should have left it to others to complete a portion of the superstructure which has given its full dimensions and compact solidity to that magnificent Temple of Nature (or rather let me again say of the God of Nature) which his mind conceived, and his hands mostly erected. Newton in his investigations had become completely aware of the perturbing forces arising from the interfering attractions of the planets on each other, &c., which affect and appear to threaten the permanent sta

bility of the system. He was, indeed, inclined to believe, that these perturbations were such as to render it necessary that the Deity should from time to time, directly and as it were miraculously, interfere (without the intervention of those general and ordinary laws of secondary means which his wisdom at first appointed) in order to rectify these disturbances, and to prevent the system from being hurried by them into disorder and destruction. But far more sublime and more worthy of the great Creator seem to me the views opened by the more recent discoveries of science, which, in pursuing to its full results and perfecting in all its details the Newtonian theory, have established, that he has from the beginning secured by a most exquisite and never to be shaken arrangement, the permanent stability of all the parts of the system that when at the first he spoke the word and they were made; when he originally commanded and they were created; by that same word he made them fast for ever and ever, and gave them a law which never shall be broken. For by fully tracing out the universal power of gravitation through all its abstruse combinations, it has at length been completely demonstrated, that all the anomalies in our system are what are called secular variations, that is, periodical inequalities, oscillating only within fixed and narrow limits; and destined, after running through a certain course, to return by a fixed appointment of nature into the same order. And that the great points of the mean distances (from the sun) and mean motions (or revolutions) of the planets being constantly invariable, all permanent and destructive effects

from the disturbing causes are thus overruled; and even in the midst of seeming danger, stability is established on the securest basis. Now, as an able exponent of these discoveries has excellently observed*, *, "When we consider the provision thus made by Nature for the stability and permanence of the planetary system, an important question arises, Whether is this stability necessary or contingent? the effect of an unavoidable or an arbitrary arrangement? for if it were the necessary consequence of conditions themselves, we could not infer from them the existence of design, but must content ourselves with admiring them as simple and beautiful truths, having a necessary and independent existence. But if, on the other hand, the conditions from which this stability arises necessarily are not necessary themselves, but the consequences of an arrangement which might have been different, we are then assuredly entitled to conclude, that it is the effect of wise design exercised in the construction of the universe.

"Now the investigations of La Place enable us to give a very satisfactory reply to these questions, viz.-That the conditions essential to the stability of a system of bodies gravitating mutually to one another are by no means necessary, insomuch that systems can easily be supposed in which no such stability exists. The conditions essential to it, are, the movement of the bodies all in one direction, their having orbits of small eccentricity, or not far different from circles, and having periods of revolution not commensurable with one another. Now these conditions are not necessary; they may * Playfair.

be easily supposed different; any of them might be changed, while the others remained the same. The appointment of such conditions, therefore, as would necessarily give a permanent and stable character to the system is not the work of necessity, and no one will be so absurd as to argue that it is the work of chance. It is therefore the work of design or of intention, conducted by wisdom and foresight of the most perfect kind."-(Ed. Review, vol. xi.)

Before I quit the subject of Astronomy, I cannot fail to point out the nice adjustment by which the physical constitution and power of the animal inhabitants and vegetable products of our own planet are so exactly adapted to the condition of that planet, as influenced by its distance from the sun, and many other circumstances; that all things here conspire together for their well-being: although the same constitution would be often inconsistent with the comfortable and vigorous existence of races similarly organized on some of the other planets. We need not indeed doubt that those other planets are equally inhabited and occupied; analogy would on the contrary rather lead us to conclude that they are all likewise fully tenanted by beings equally adjusted to their respective situations. But this nice adjustment, by which every thing is rendered exactly suitable to the physical circumstances of its particular situation, most clearly implies design and intelligence. To illustrate this, let us consider how animals and vegetables like those with which we are acquainted would fare if they had been called into existence on the face of Jupiter instead of the Earth, which is certainly a