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Newtonian doctrine of the universal attraction of matter to matter. At the beginning of the present century it was thought impossible, by the disciples of the British philosopher, that any man, capable of either writing or reading his own name,
would oppose any of the grand principles of their master's system. But this was a vain fancy: for, very shortly after, a lively Frenchman, M. Mercier, stept forward as an active reformer of that celebrated school, and in a treatise of 318 pages, De l'Impossibilité du Systéme Astronomique de Copernic et de Newton, endeavoured to demonstrate irrefragably that this system is utterly impossible. His logic was worthy of an opposer of Newton, and ran thus : “ We know nothing of matter, but the universe is constituted of matter; therefore the Copernican and Newtonian system is impossible.” “A point is that which has neither parts nor dimensions ; but geometrical figures are made up of points; and mathematicians, one of whom was le grand mistificateur Newton, deduce their conclusions from reasonings upon geometrical figures; therefore the astronomical system of Copernicus and Newton is impossible.”
66 Locke was the worst of metaphysicians, and corrupted the source of morals; therefore, &c.' " A French astrologer endeavoured to illustrate the nature of parallax by pointing to a lady's bonnet; therefore, &c.” « Voltaire sometimes ridiculed Descartes, sometimes Maupertuis, and sometimes Newton; therefore, &c." And after syllogizing in this way through 37 chapters, he settles the point beyond all controversy, thus---". Mathematical demonstration is not applicable to moral subjects, whence it follows indubitably that the astronomical system of Copernicus and Newton is impossible.” Such forcible reasoning as this, must, of necessity, carry all the world before it; and probably M. Mercier would have been deputed to frame a new system for astronomers, had not some prying wight discovered that he hard long been under the influence of
• The queen of night, whose vast command
• In high spring.tides at midnight reigns.' Whether it be that our present author, in imitation of so splendid an example, prepare his monthly lucubrations as M. Mercier is said to have done, always within a day or two of the full-moon; or whether his reasoning be the genuine result of his own powers, independently of all influence ab extra ; certain it is, that there is a great similarity in the mode of argumentation adopted by the French and the English reformer.
Mr. Frend . ventures to call in question the existence of attraction, the great cause, as it has been supposed, of the heavenly bodies being retained in their orbits;' and, that our readers may know with what skill and force he opposes this prevailing notion, we shall select a few specimens of his reasons.
1. ' How far the system of attraction has a claim to our belief, either from the authority of a name, or from the thing itself, it may not be useless to inquire; but it is certain that if we cannot conceive it to exist (just as the Siamese could not conceive ice to exist ---since existences, notoriously depend altogether upon our ignorance), however plausible the theory may be which is formed upon it, the doctrine itself must share the fate of the crystalline orbs, and serve to warn us against too rash a decision on subjects beyond the reach of our ken [query, ken of our reach?j Though we should banish attraction from the regions of astronomy, the science will not suffer.' (p. 25.) Therefore, the motions of the planets are produced by a cause of an opposite nature.' p. iv.
2. Newton lays down, from demonstration, the laws to which horses, or any other bodies, would be subject in revolving round a centre. These bodies, in their motions, he conceives to be acted upon by a force, which he calls the centreseeking force; and it is in this term that many mistakes originate.' (p. 39.) Therefore the astronomical doctrine of attraction ought to be exploded.
3. When regimental horses, with their riders, go round and round in the same ring, for a great length of time, the space within the ring is void ; and though the horses may be said to be acted upon by a centre-seeking force, the men who direct their motions would be very much puzzled to understand the nature of its operation.' (p. 41.). Therefore, the astronomical doctrine of attraction ought to be exploded.
4. When we see a cork in a mill-pond moved round and round by the force of the water, we have an instance of a curvilinear motion, in which the body moved is perfectly passive.' (p. 41.) Therefore, the astronomical doctrine of attraction, &c.
5. • We must attribute the motion of a body in a curve to some cause, which it will be our business to discover; it may be with ease, or with difficulty, or, perhaps, it may be beyond the reach of our powers that is, as before remarked, the
reach of our ken,' or the ken of our reach.] In all cases, we should be careful of affirming positively without due investigation. But the business of the month now calls us to another employment.' (p. 42.) Therefore the astronomical doctrine, &c. as before.
6. When a body revolves in a curve, it is said to be acted upon by a force, which is called centripetal, or centre-seeking but we are not at a loss for instances in which bodies do revolve in a curve, and yet there is nothing within the curve to act upon those bodies.' (p. 55.) Therefore, &c.
7. ' A newspaper brought in wet from the press, is held to the fire to dry, and not unfrequently it is soiled by the bars, and sometimes burnt. The person who holds it hears this language : “ Take care, the fire is drawing the paper; if you don't mind it will be burnt.” Now here is appa 7 rently an attraction' (p. 56) ; but there is none in reality Therefore, &c. as before.
8.' A boy amuses himself by taking a piece of round leather, through which he passes a string, and having soaked it for some time in water, he places it on a stone, treading it firmly on; and from this time the stone and leather adhere together; and he carries it [query, which ?] about, hanging at the bottom of his string. Whilst the leather is dry, he may tread it down as long as he pleases on the stone, but no such effect will be produced, no adhesion will take place. On pulling the string the leather feels the impulse Indeed?] but the stone is left behind.' (p. 59.) This cannot be accounted for by attraction alone, though the vulgar perhaps, as in the former example, think it may :' therefore, &c. as before.
9. 'A very able writer (Boscovich) not being able to get over a certain objection, has formed his system by allowing to matter both attractive and repulsive powers.' • He carried the system of Newton to its farthest extent.' (p. 75.) Therefore the notion of universal attraction must be exploded.
10." A living writer (Bonnycastle) talks of heresy, and worst of heretics, in a question of philosophy :' (pp. 98, 99) ---which, to be sure, is somewhat ridiculous : therefore, &c.
11. Mr. Bridge, in his Elements of Algebra, says that the traveller arrives at his journey's end at the conclusion of the ninth day; but by going on for six days longer, resting on the sixteenth day, and travelling back again for the last six days, he will, algebraically speaking, arrive at his journey's end again at the conclusion of the twenty-second day.' (p. 102.) Therefore the Newtonian doctrine of attraction is utterly untenable.
12. The doctrine of ultimate ratios is so abstruse, that Mr. Frend cannot comprehend it. (p. 118 :) therefore, &c. as before.
13. Mr. Frend explains the phenomenon of the melting of a piece of sugar in water,' by inventing a new word,' hydatic,' and by employing very ambiguously two common words, connection and combination (p. 149.) : therefore, &c.
14. ' I do not allow the approach of the moon to the earth to be owing to any attractive force existing in either orb [how poetical, as well as philosophical!] ; but I may be as wrong as those who have gone before me in assigning the cause.' (p. 165.) Therefore, &c.
15. No one admires the genius of Newton more than my. self; yet I cannot be blind to his faults, nor will the superiority of his talents compel me to assent to a doctrine, which so far from being founded on demonstration, is mere conjecture and hypothesis.' (p. 99.) Therefore the Newtonian doctrine of attraction is mere conjecture and hypothesis.'
Such of our readers as are prone, to use Dean Milner's expression, to look “ for the nucleus of an argument, which they would gladly separate from all the extraneous materials with which it is involved," will be delighted to see with what logical dexterity Mr. Frend contrives to make his reasonings strike home to every understanding. Such simplicity, such cogency, such elegance of illustration! Had Newton met with such an opponent in his days, he would surely have died, broken-hearted, long before he attained the age of 85. But the most notable specimen of our author's skill as a reasoner (or we might say, as “a wrangler," for Mr. Frend was " second wrangler" in his year) is yet to be produced. As he seems to think it very decisive, we shall present it entire, notwithstanding its length.
• Newton took up the question that Kepler had left unsolved, and he laid down a law, by which every thing, at first sight, seems easy of explanation. But, on examining it more closely, we are brought into a dilemma, from which it will not be easy to extricate ourselves. The law of Newton is certain, provided bodies revolve in orbits of the form he lays down ; but if they do not revolve in orbits of such a form, then the law is different, and the conclusions, of course, will vary:
• For example, if the planetary bodies are actuated upon (such is the technology of the Frendean philosophy] by one law of force, then their periodical times and distances will bear a certain proportion to each other, and the curves they describe will be ascertained; in short they will be what Kepler has asserted them to be ; and if the curves are supposed to be what Kepler has described, then the law of the force will be that which Newton has laid down. We come, then, to the enquiry, whether the assertions of the two great philosophers are compatible with each other. Kepler asserts, that the planets move in orbits, which are elliptical, with a certain proportion between their periodical times and mean distances; and Newton asserts, that they are actuated by a force, varying inversely as the square of the distance; as no other force could produce such motions.
• Now let us take Newton's opinion first, and suppose, that his force exists in nature ; then, how can the planets move in elliptical orbits ? For let the Sun, Earth, and Moon, be in any position you please, when the Earth is one point of its orbit, then they will not be in the sarne position, when the Earth returns to that point. Consequently, they will be acted upon in a different manner from what they were, when the Earth was first in this point; and the curve described by the Earth in the second case, must, therefore, vary from what it
was in the hrst case. This will be true of every point in the Earth's orbit, which, therefore, cannot be elliptical; and no two orbits of the Earth will be for many hundred years, if they ever are, the same, Hence, if Newton's law is true, that of Kepler is false.
Now, let us suppose, with Kepler, who knew nothing of the forces of which we are talking, that the planets move in elliptical orbits, then each of them would be acted upon necessarily by the force laid down by Newton, provided there was no action of the one upon the other. If they do act each upon the other, then there will be a force at one time added to, and at another subtracted from that of the Sun; and, consequently, since the whole force must follow one law, that of the Sun and the planet cannot follow this law, but their forces must be such as, by combination, to form this law. Hence, if Kepler's law is true, that of Newton is false.
! We are brought, then, to this conclusion, that the laws laid down by these great men, are neither of them true. The attempt to de. scribe the path of the heavenly bodies is one of noble daring ; nor was it less to assign the cause of their motions; but can we imagine, that the unerring hand of Omnipotence is to be thus guided by our arithmetic, by laws of human calculation !
• The moon is on the meridian on the 1st, at 48 minutes past six in the evening, being under the four stars in square, the two western being to the west, and the two eastern to the east of the meridian; the former being nearest to it.' p. 180.
That the preceding argument may lose nothing of its force by being terminated abruptly, we have introduced the passage relative to the moon's southing, to which we apprehend our author attaches great importance; as we observe that he always seems eager to slip from the dryer parts of his discussions, and introduce a word or two respecting his favourite luminary. ! On the 2d of this month the moon's crescent is seen, for a short time, above Aldebaron.' . At night, on the 12th, the moon rises to the east of the small stars in the tail of the Goat.'
Am I endeavouring to overthrow the mathematics and the phi, losophy of Newton? By no means. On the 26th, the cresçent of the moon will be seen, soon after sunset, near the horizon, in the west-south-west :' and so on.
But we must if possible, become serious before we close the present article, and approach this formidable • dilemma' upon which our acute author has thrown the poor Newtonians. The truth is (and so Mr. Frend must know, unless he have forgotten all he learnt at Cambridge), that Kepler found, from observation, that the planets in their revolutions about the sun moved nearly in ellipses: the truth is also, that Newton demonstrated that, if a central body be in the focus of a conic section, and another body move in the curve of that section, the centripetal force will be inversely as the square of the distance froin the focal or central body: the truth is, farther, that when the Newtonian law