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quate if we do not mentally co-ordinate the idea of force with that of motion, and recognize it as the "efficient cause" of those phenomena-the "material conditions" constituting (to use the old scholastic term) only " their formal cause." And I lay the greater stress on this point, because the mechanical philosophy of the present day tends more and more to express itself in terms of motion rather than in terms of force-to become kinetics instead of dynamics.

Thus, from whatever side we look at this question, whether the common sense of mankind, the logical analysis of the relation between cause and effect, or the study of the working of our own intellects in the interpretation of Nature,-we seem led to the same conclusion; that the notion of force is one of those elementary forms of thought with which we can no more dispense, than we can with the notion of space or of succession. And I shall now, in the last place, endeavor to show you that it is the substitution of the dynamical for the mere phenomenal idea, which gives their highest value to our conceptions of that order of nature which is worshipped as itself a god by the class of interpreters whose doctrine I call in question.

The most illustrative as well as the most illustrious example of the difference between the mere generalization of phenomena and the dynamical conception that applies to them, is furnished by the contrast between the so-called laws of planetary motion discovered by the persevering ingenuity of Kepler, and the interpretation of that motion given us by the profound insight of Newton. Kepler's three laws were nothing more than comprehensive statements of certain groups of phenomena determined by observation. The first, that of the revolution of the planets in elliptical orbits, was based on the study of the observed places of Mars alone,-it might or might not be true of the other planets; for, so far as Kepler knew, there was no reason why the orbits of some of them might not be the excentric circles which he had first supposed that of Mars to be. So Kepler's second law of the passage of the Radius Vector over equal areas in equal times, so long as it was simply a generalization of facts in the case of that one planet, carried with it no reason for its applicability to other cases, except that NEW SERIES.-VOL. XVI., No. 4.

which it might derive from his erroneous conception of a whirling force. And his third law was in like manner simply an expression of a certain harmonic relation which he had discovered between the times and the distances of the planets, having no more rational value than any other of his numerous hypotheses.

Now the Newtonian "laws" are often spoken of as if they were merely higher generalizations in which Kepler's are included; to me they seem to possess an altogether different character. For starting with the conception of two forces, one of them tending to produce continuous uniform motion in a straight line, the other tending to produce a uniformly accelerated motion towards a fixed point, Newton's wonderful mastery of geometrical reasoning enabled him to show that, if these dynamical assumptions be granted, Kepler's phenomenal "laws," being necessary consequences of them, must be universally true. And while that demonstration would have been alone sufficient to give him an imperishable renown, it was his still greater glory to divine that the fall of the moon towards the earth-that is, the deflection of her path from a tangential line to an ellipse-is a phenomenon of the same order as the fall of a stone to the ground; and thus to show the applicability to the entire universe, of those simple dynamical conceptions which constitute the basis of the geometry of the Principia.

Thus, then, whilst no "law" which is simply a generalization of phenomena can be considered as having any coercive action, we may assign that value to laws which express the universal conditions of the action of a force, the existence of which we learn from the testimony of our own consciousness. The assurance we feel that the attraction of gravitation must act under all circumstances according to its one simple law, is of a very different order from that which we have in regard (for example) to the laws of chemical attraction, which are as yet only generalizations of phenomena. And yet even in that strong assurance, we are required, by our examination of the basis on which it rests, to admit a reserve of the possibility of something different-a reserve which we may well believe that Newton himself must have entertained.

A most valuable lesson as to the allowance we ought always to make for the un

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known "possibilities of nature," is taught us by an exceptional phenomenon so familiar that it does not attract the notice it has a right to claim. Next to the law of the universal attraction of masses of matter, there is none that has a wider range than that of the expansion of bodies by heat. Excluding water and one or two other substances, the fact of such expansion might be said to be invariable; and, as regards bodies whose gaseous condition is known, the law of expansion can be stated in a form no less simple and definite than the law of gravitation. Supposing those exceptions, then, to be unknown, the law would be universal in its range. But it comes to be discovered that water, whilst conforming to it in its expansion from 392° upwards to its boiling-point, as also, when it passes into steam, to the special law of expansion of vapors, is exceptional in its expansion also from 392 downwards to its freezing-point; and of this failure in the universality of the law no rationale can be given. Still more strange is it, that by dissolving a little salt in water, we should remove this exceptional peculiarity; for seawater continues to contract from 392° downwards to its freezing-point 12° or 14° lower, just as it does with reduction of temperature at higher ranges.

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Thus, from our study of the mode in which we arrive at those conceptions of the orderly sequence observable in the phenomena of Nature which we call "laws," we are led to the conclusion that they are human conceptions, subject to human fallibility; and that they may or may not express the ideas of the Great Author of Nature. To set up these laws as self-acting, and as either excluding or rendering unnecessary the power which alone can give them effect, appears to me as arrogant as it is unphilosophical. To speak of any law as "regulating" or "governing" phenomena, is only permissible on the assumption that the law is the expression of the modus operandi of a governing power. once in a great city which for two days was in the hands of a lawless mob. Magisterial authority was suspended by timidity and doubt; the force at its command was paralyzed by want of resolute direction. The "laws" were on the statute book, but there was no power to enforce them. And so the powers of evil did their work; and are and rapine continued to destroy life and property without check until new pow

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er came in, when the reign of law was restored.

And thus we are led to the culminating point of man's intellectual interpretation of Nature-his recognition of the unity of the power, of which her phenomena are the diversified manifestations. Towards this point all scientific inquiry now tends. The convertibility of the physical forces, the correlation of these with the vital, and the intimacy of that nexus between mental and bodily activity, which, explain it as we may, cannot be denied, all lead upward towards one and the same conclusion; and the pyramid of which that philosophical conclusion is the apex has its foundation in the primitive instincts of humanity.

By our own progenitors, as by the untuored savage of the present day, every change in which human agency was not apparent was referred to a particular animating intelligence. And thus they attributed not only the movements of the heavenly bodies, but all the phenomena of Nature, each to its own deity. These deities were invested with more than human power; but they were also supposed capable of human passions, and subject to human capriciousness. As the uniformities of Nature came to be more distinctly recognized, some of these deities were invested with a dominant control, while others were supposed to be their subordinate ministers. A serene majesty was attributed to the greater gods who sit above the clouds, whilst their inferiors might " come down to earth in the likeness of men." With the growth of the scientific study of Nature, the conception of its harmony and unity gained ever-increasing strength. And so among the most enlightened of the Greek and Roman philosophers, we find a distinct recognition of the idea of the unity of the directing mind from which the order of Nature proceeds; for they obviously believed that, as our modern poet has expressed it,

All are but parts of one stupendous whole.
Whose body Nature is, and God the Soul.

The science of modern times, however, has taken a more special direction. Fixing its attention exclusively on the order of Nature, it has separated itself wholly from theology, whose function it is to seek after its cause. In this, science is fully justified, alike by the entire independence of its objects, and by the historical fact that it has

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the two lifeless logs, and determining to show more sense for the future. But when the two stools assume the human form, have eyes that speak a silent language, encounter you day after day, and seem always to wear a mocking smile as if in derisive remembrance of your misadventure, the matter wears a more serious aspect. And in Bushby's case the stools wore petticoats, which added to the discomfort of the situation.

THE FIRST STOOL.

"The question is what to do with that horrid Mr. Bushby."

These words were uttered on a certain day, about two years before Bushby's emigration, and the speaker was a particularly amiable-looking lady of some forty-five years of age. She was speaking to herself, as she gazed with a well-satisfied air at an arbor of which she commanded a full view from the open window at which she was seated. For it was a lovely day in June, and the weather was eminently suited for the occupation of an interesting couple, who sat upon two wicker chairs under a shady, leafy roof, in a garden gay with roses. They were, in fact, doing nothing; unless carrying on a conversation in a low tone may be considered doing something. They both were young and of different sexes. He was about six-and-twenty, one would have said, and she was five years younger. She had a face and figure which were pleasing rather than pretty; and the former wore an expression such as is frequently the result of recent illness or mental trouble. He who sat by her was her not yet accepted lover; and the lady at the window was her mother. The daughter suddenly rose up in obedience to a sign, and stood before the amiable-looking matron of forty-five.

"Annie, darling," said the latter, "I think your birthday is some day this week." "Yes, dear mamma, on Friday." "And this is only Tuesday; there is plenty of time. That is all I wanted, darling."

Annie went back to her seat in the arbor; and the amiable-looking matron looked more amiable than ever, for she had hit upon a satisfactory plan. She now knew perfectly well "what to do with that horrid Mr. Bushby." She was an excellent mother; which means that she had at

heart her daughter's comfortable settlement in life, and was ready to do anything short of felony to secure it. She had constantly impressed upon Annie, that in matrimonial matters young ladies have nothing to do with affections until they have ascertained that he who might be the object of them can make suitable provision for a wife; and, afterwards, they may bestow them freely. She had even gone so far as to maintain that love is all nonsense in these days of civilization; that it was quite enough if a young lady proposed to did not actually dislike the proposer; that there was nothing so likely to promote conjugal affection as the possession of a nice little income-which was her way of rendering "sine Baccho et Cerere friget Venus." She was also fond of inculcating the wisdom of that proverb which says that "a bird in the hand is worth two in the bush." She held it to be the height of madness to refuse a present certainty in the hope of future contingencies; to decline what Tomkins offered on the spot, in the expectation of what Bushby might some day offer.

That was Tomkins, of course, who was sitting in the arbor; and he had already offered his hand, his heart, and eight hundred a year. He was to receive a definite answer in a week; and there was upon his features, as he sat and conversed in desultory fashion with Annie, an expression which might mean either that he considered he had already made a fool of himself, or that he expected to be made a fool of in the course of a week. In fact, he looked uneasy and anything but confident. In the pauses, which were many and pretty long, between the different portions of a fragmentary dialogue, he took furtive, sidelong glances at Annie, after the fashion of one who is examining an article for which he has impulsively made a bid, and which he half hopes and half fears will be ultimately knocked down to him. As for Annie, she, during those intervals, gazed far away into vacancy with the air of one whose thoughts are occupied with by no means the pleasantest of day-dreams; and she plucked the while leaf after leaf from a rose she held, as if she were silently testing her fate with the well-known alternations of "loves me, loves me not." When the last leaf had fluttered to the ground and the stalk had been listlessly dropped after it, she rose up wearily and said coldly to her companion.

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