Page images
PDF
EPUB

SIR ISAAC NEWTON.

BY

LORD BROUGHAM.

(An Oration spoken at the Inauguration of the National Statue of Sir

Isaac Newton, at Grantham, Lincolnshire.)

TO RECORD the names and preserve the memory of those whose great achievements in science, in arts, or in arms, have conferred benefits and lustre upon our kin), has in all ages been regarded as a duty and felt as a gratification by wise and reflecting men. The desire of inspiring an ambition to emulate such examples, generally mingles itself with these sentiments; but they cease not to operate even in the rare instances of transcendant merit, where matchless genius excludes all possibility of imitation, and nothing remains but wonder in those who contemplate its triumphs at a distance that forbids all attempts to approach. We are this day assembled to commemorate him of whom the consent of nations has declared, that he is chargeable with nothing like a follower's exaggeration or local partiality, who pronounces the name of Newton as that of the greatest genius ever bestowed by the bounty of Providence, for instructing mankind on the frame of the universe, and the laws by which it is governed "Qui genus humanum ingenio superavit, et omnes

Restinxit ; stellas exortus uti ætherius sol.”-- (Luc.) "In genius who surpassed mankind as far

As does the mid-day sun the midnight star.”—(DRYDEN.) But, though scaling these lofty heights be hopeless, yet there is some use and much gratification in contemplating by what steps he ascended. Tracing his course of action may help others to gain the lower eminences lying within their reach, while admiration excited and curiosity satisfied are frames of mind both wholesome and pleasing. Nothing new, it is true, can be given in narrative, hardly anything in reflection, less still perhaps in comment orillustration; but it is well to assemble in one view various parts of the vast subject, with the surrounding circumstances, whether accideutal or intrinsic, and to mark in passing the misconceptions raised by individual ignorance or national prejudice which the historian of science occasionally finds crossing his path.

The remark is common and is obvious, that the genius of Newton did not manifest itself at a very early age. His faculties were not, like those of some great and many ordinary individuals, precociously developed. Among the former, Clairant stands preeminent, who at 19 years of age presented to the Royal Academy a memoir of great originality upon a difficult subject in the higher geometry, and at 18 published his great work on curves of double curvature, composed during the two preceding years. Pascal, too, at 16, wrote an excellent treatise on conic sections. That Newton cannot be ranked in this respect with those extraordinary persons, is owing to the accidents which prevented him from entering upon mathematical study before his 18th year; and then a much greater marvel was wrought than even the Clairants and the Pascals displayed. His earliest history is involved in some obscurity, and the most celebrated of men has, in this particular, been compared to the most celebrated of rivers (the Nile), as if the course of both in its feebler state had been concealed from mortal eyes.

We have it, however, well ascertained that within four years, between the age of 18 and 22, he had begun to study mathematic science, and had taken his place among its greatest masters; learnt for the first

time the elements of geometry and analysis, and discovered a calculus which entirely changed the face of the science, effecting a complete revolution in that and in every branch of philosophy connected with it Before 1661 he had not read Euclid; in 1665 he had committed to writing the method of fluxions. At 25 years of age he had discovered the law of gravitation, and laid the foundation of celestial dynamics, the science created by him. Before ten years had elapsed he added to his discoveries that of the fundamental properties of light.

So brilliant a course of discovery in so short a time, changing and reconstructing analytical, astronomical, and optical science, almost defies belief. The statement can only Debemed possible by an appeal to the incontestible evilence that proves it strictly true. By a rare felicity these doctrines gained the universal assent of inankind as soon as they were clearly understood; and their originality has never been seriously called in qnestion.

Some doubts having been raised respecting his inventing the calculus--doubts raised in consequence of his so long withholding the publication of his methodno sooner was the inquiry instituted than the evidence produced proved so decisive, that all men in all countries acknowledged him to have been by several years the earliest inventor, and Leibnitz, at the utmost, the first publisher; the only questions raised being, first, whether or not he had borrowed from Newton; and next, whether, as second inventor, he could have any merit at all; both which questions have long since been decided in favour of Newton. But undeniable though it be that Newton made the great steps of this progress, and made them without any anticipation or participation by others, it is equally certain that there had been approaches in former times by preceding philosophers to the same discoveries. Cavalleri, by his Geometry of Indivisibles (1635), Roberval, by his Method of Tangents (1367), had both given solutions

which Descartes could not attempt; and it is remarkable that Cavalleri regarded curves as polygons, surfaces as composed of lines, while Roberval viewed geometrical quantities as generated by motion; so that the one approached to the differential calculus, the other to fluxions; and Fermat, in the interval between them, comes still nearer the great discovery by his determination of maxima and minima, and his drawing of tangents. More recently Hudden had made public similar methods invented by Schoetin; and what is material, treating the subject algebraically, while those just now mentioned had rather dealt with it geometrically.

It is thus easy to perceive how near an approach had been made to the calculus before the great event of its final discovery. There had in like manner been approaches made to the law of gravitation, and the dynamical system of the universe. Galileo's iinportant propositions on motion, especially on curvilinear motion, and Kepler's laws upon the elliptical form of the planetary orbits, the proportion of the areas to the times, and of the periodic times to the mean distances; and Huygens's theorems on centrifugal forces,—had been followed by still nearer approaches to the doctrine of attraction. Borelli had distinctly ascribed the motion of satellites to their being drawn towards the principal planets, and thus prevented from flying off by the centrifugal force. Even the composition of white light, and the different action of bodies upon its component parts, had been vaguely conjectured by. Ant. de Dominis, archbishop of Spalatro, at the beginning, and more precisely in the middle, of the 17th century by Marcus (Kronland, of Prague), unknown to Newton, who only refers to the archbishop's work; while the treatise of Huygens on light, Grimaldi's observations on colours by inflexion, as well as on the elongation of the image in the prismatic spectrum, had been brought to his attention, although much less near to his own great discovery

than Marcus's experiment. But all this only shows that the discoveries of Newton, great and rapid as were the steps by which they advanced our knowledge, yet obeyed the law of continuity, or rather of gradual progress, which governs all human approaches towards perfection. The limited nature of man's faculties precludes the possibility of his ever reaching at once the utmost excellence of which they are capable. Survey the whole circle of the sciences, and trace the history of our progress in each, you find this to be the universal rule. In chymical philosophy the dreams of the alchymists prepared the way for the more rational, though erroneous, theory of Stahl; and it was by repeated improvements that his errors, so long prevalent, were at length exploded, giving place to the sound doctrine which is now established.

The great discoveries of Black and Priestley on heat and aeriform fluids, had been preceded by the happy conjectures of Newton, and the experiments of others. Nay, Voltaire had well nigh discovered both the absorption of heat, the constitution of the atmosphere, and the oxydation of metals ; and by a few more trials might have ascertained it. Cuvier had been preceded by inquirers who took sound views of fossil osteology, among whom the truly original genius of Hunter fills the foremost place. The inductive system of Bacon had been, at least in its practice, known to his predecessors. Obser. vations and even experiments were not unknown to the ancient philosophers, though mingled with gross errors : in early times, almost in the dark ages, expérimental inquiries had been carried on with success by Friar Bacon, and that method actually recomInended in a treatise, as it was two centuries later by Leonardo da Vinci: and at the latter end of the Tiext century Gilbert examined the whole subject of magnetic actiou entirely by experiments. So that Lord Bacon's claim to be regarded as the father of modern philosophy, rests upon the important, the in

« EelmineJätka »