Sir Isaac Newton_By Bernard le Bovier de Fontenelle

The Life of Sir Isaac Newton;with an Account of his Writings.

By Bernard le Bovier de Fontenelle

(London: 1728)
Transcribed by David R. Wilkins (2002)

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Sir ISAAC NEWTON was born at Wolstrop in the County of Lincoln on Christmas-day, O. S. in the year 1642. He was descended of the eldest Branch of the Family of Sir John Newton, Bart. who were Lords of the Manor of Wolstrop, and have been possess'd of the Estate for near 200 years. The Newtons had remov'd thither from Westby in the same County, but originally came from the Town of Newton in Lancashire. His Mother's name was Anne Ayscough, who was also of an antient Family, and married again after his Father's Decease.

She sent her Son to the Free-School of Grantham at twelve years old, and took him thence within a few years after, that she might make him early acquainted with his own affairs, and learn to look after them himself. But she found him so little dispos'd towards an application for Business, and so entirely given up to his Book, that she soon sent him back to Grantham, with free leave to follow his own Inclinations. And these he afterwards pursued with the greatest Satisfaction, by removing from thence to Trinity College in Cambridge, where he was admitted in 1660. at the age of eighteen.

In studying Mathematicks, he employ'd his Thoughts very little upon Euclid, as judging him too plain and easy to take up any part of his time; he understood him almost before he had read him, and by only casting his eye upon the Subject of a Proposition, was able to give the Demonstration. He launch'd at once into such Books as the Geometry of Des Cartes and the Opticks of Kepler. So that we may justly apply to him what Lucan has said of the Nile, whose Springs were unknown to the Antients, That it was not granted to Mankind to see the Nile in a small Stream. It can be prov'd, that Sir Isaac Newton had made his great discoveries in Geometry, and laid the Foundation of his two famous Performances, the Principia and the Opticks, by that time he was four and twenty years old. If the intelligent Beings, superiour to Man, do also make a progress in Knowledge, they fly whilst we creep, and pass over without notice the intermediate steps, by which we slowly advance from the perception of one truth to another, which has a dependence upon it.

In 1668. Nicholas Mercator, a Native of Holstein, who had pass'd the best part of his time in England, publish'd his Logarithmotechnia, in which he resolv'd the Area of an Hyperbola into an infinite Series. This was the first time such a method of Calculation, so dextrously drawn from the nature of a particular Curve, had appear'd in the World. The learned Dr. Barrow, at the time residing at Cambridge with Sir Isaac Newton, who was then in his seven and twentieth year, recollected streight, that he had seen the same Theory among the Compositions of this young Gentleman, tho' not confin'd to the Hyperbola in particular, but extended by general rules to all sorts of curvilinear Figures, even to mechanical Curves, to their Quadratures, Rectifications, and Centres of Gravity, to Solids form'd by their Revolutions, and the Surfaces of such Solids; so that if the Determinations were possible, the Series would terminate at a certain point, or if they did not terminate, their sums might be had by rule; and if the precise Determinations could not be obtain'd, yet nearer approaches might still be made towards Infinity; the happiest and most artful Scheme which the wit of Man could have ever invented for supplying the imperfection of his own knowledge.

'Twas a great treasure for a Mathematician to be possess'd of so fruitful and so general a Theory; 'twas a still greater glory to have been the inventor of a Theory so surprising and ingenious; and 'twas natural for Sir Isaac Newton, when he saw by Mercator's Book, that he was upon the right pursuit, and that others might follow him in it, to have laid open his treasure at large, and secur'd to himself the right of property, arising from the discovery. But he was satisfied with the enjoyment of it, without being at all sollicitous about the glory attending it. He says himself in one of his letters in the Commercium Epistolicum, that he thought his secret had been entirely discover'd by Mercator, or would have been by others, before he should have been of a proper age to have disclos'd it. He suffer'd the honour of an Invention to be ravish'd from him without regret, from whence he might have promis'd himself the largest returns of praise; and tho' he lost no time in the pursuit of the noblest Attempts, yet he waited 'till he was of a convenient age to shew himself to the World. His Manuscript was only communicated to Mr. Collins and my Lord Brounker, who were distinguish'd by their Skill in these matters; and even this could not be obtain'd but by the mediation of Dr. Barrow, who would not suffer him to indulge his Modesty to the utmost length of his Inclination.

This Manuscript, which the Author gave out of his hands in 1669. was entitled, A Method, which I had formerly found out, &c. Now if the word formerly be suppos'd only to comprehend three years, this beautiful Theory must have been discover'd before he was four and twenty years old. The same Manuscript farther contains the Invention and Calculation of Fluxions, which have occasion'd so great a Dispute between Mr. Leibnitz and Sir Isaac Newton, or rather between Germany and England. We gave the History of it in 1716. in our Panegyrick upon Mr. Leibnitz; and tho' our business was then to praise Mr. Leibnitz, yet we there so exactly observ'd the Impartiality of an Historian, that we have nothing more to add at present with reference to Sir Isaac Newton. We expressly declar'd, that Sir Is. Newton was certainly the Inventor; that the Glory of it was undoubtedly his due; and that the Dispute was only whether Mr. Leibnitz had borrow'd his notion from him. All England is convinc'd that he did, tho' the Royal Society have not been decisive in their Judgment upon it. Sir Isaac Newton's Invention preceded the publication of Mr. Leibnitz by several years. Mr. Leibnitz on the other hand is the first who ever made this Method of Calculation publick; and if he has taken it from Sir Isaac Newton, he has at least resembled Prometheus in the Fable, who stole Fire from the Gods, that he might communicate it to Men.

In 1687. Sir Isaac Newton at last determin'd to throw off the Veil, and let the World see what manner of Man he was; 'twas then he publish'd his Mathematical Principles of Natural Philosophy. This Book, in which he has built a new System of Physicks upon the deepest reasonings in Geometry, did not at first meet with all the applause it deserv'd, and which it was one day to receive. As it is written with a great deal of learning, as the Author has been very sparing of his expressions, and the conclusions are often so hastily drawn from the premisses, that the Reader is frequently left to supply an intermediate chain of Consequences, it requir'd some time before the Publick could be able to understand it. Mathematicians of character were oblig'd to study it with care, before they could be masters of it; and those of a lower rank did not dare to venture upon it, till encourag'd by the more learned; but at last, when the Book came to be sufficiently known, the approbation, which had been so slowly gain'd, became so universal, that nothing was to be heard from all quarters but one general cry of Admiration. Mankind were amaz'd at the masterly Strokes, which shone throughout the Work, and stood astonish'd at the vast Genius for Invention discover'd in it, which in all the Countries of the learned World hardly ever shews itself in above three or four Persons during the whole extent of a most fruitful Age.

There are two principal Theories, which prevail above the rest in the Principia Mathematica, the doctrine of centripetal Forces, and of the resistance of Fluids to Bodies moving in them; these are both almost entirely new, and treated of according to the Author's sublime method of reasoning in Geometry. There's no possibility of touching upon either of these points without having Sir Isaac Newton before our eyes, without copying from him, or treading after him, and should we endeavour to conceal it, 'twould be hardly practicable with all our address to prevent its being known.

The relation observ'd by Kepler between the revolutions of the heavenly Bodies, and their distances from the centre of those Revolutions, holds good throughout the whole celestial System. If we suppose, as we necessarily must, that a certain force restrains those great Bodies from proceeding to move according to their natural direction in a right line from West to East, and draws 'em continually towards a particular Centre, it will follow from Kepler's rule, that this central or centripetal Force will have a different action upon the same Body according to its different distances from this centre, and that in a reciprocal proportion of the squares of those distances; so as, for instance, if the Body be twice as far distant from the Centre of its revolution as before, the action of the central Force upon it will be four times less. Sir Isaac Newton's System seems to have been founded upon this Observation. We may also suppose or imagine that the Moon first fell under his consideration, as it has the Earth for the centre of its Motion.

Were the Moon to lose all the impulse, by which it has a tendency to move in a right line from West to East, and the central Force only, by which it is drawn towards the centre of the Earth, were left remaining, 'twould solely obey that Force, and following its direction only, would move in a right line towards the centre of the Earth. The motion of its revolution being known, Sir Isaac Newton demonstrates that by this motion it would describe 15 Paris feet in the first minute of its descent. The distance of the Moon from the Earth is 60 of the Earth's semidiameters; by the time therefore it would have arrived at the surface of the Earth, the action of the Force, which brought it thither, would be encreas'd by the square of 60, that is, it would be 3600 times greater than in the first minute, and thus the Moon in the last minute would describe 3600 times 15 feet.

Now if we suppose, that the force acting upon the Moon is the same with that which we call Gravity in Bodies upon Earth, it would follow from the System of Galileo, that the Moon, which upon its coming to the Earth would have describ'd 3600 times 15 feet in one minute, must also have describ'd 15 feet in the first 60th part, or in the first second of that minute. Now we learn from Experiments, which indeed can only be made at small distances form the Earth's surface, that heavy Bodies let fall upon the Earth decribe 15 feet in the first second of their fall. They are therefore, with respect to the times of their descent, precisely in the same case, as if having made the same revolution round the Earth as the Moon, and at the same distance, they were let fall by the sole force of their Gravity: If then they are in the same case with the Moon, the Moon is in the same case with them, and is only drawn towards the centre of the Earth every moment by the force of the same Gravity. So exact a conformity, or rather so perfect an identity, of Effects can only arise from an identity of causes.

'Tis true, that in the System of Galileo, which we have hitherto follow'd, Gravity is supposed to be every where the same, whereas the centripetal force of the Moon is shewn to be different in the very demonstration we have just now given. But the reason is, that in all our Experiments the greatest height, from whence we can let any Bodies fall, bears no proportion to the distance of 1500 Leagues, they are all at from the centre of the Earth. 'Tis demonstrable, that a Canon-ball discharg'd horizontally, upon the supposition of an uniform Gravity, describes a Parabola, which is terminated in one point by the place where it first falls to the Ground; but was it discharg'd from an eminence high enough to make the inequality of the action of Gravity sensible, it would describe an Ellipsis instead of a Parabola, which would have the centre of the Earth for one of its Focus's, that is, it would do exactly the same thing as the Moon does.

If the Moon is heavy after the same manner as all Bodies upon Earth are heavy; if it is drawn towards the Earth by the same force, which draws them thither; if according to Sir Isaac Newton's expression it gravitates towards the Earth, the same principle prevails throughout all the wonderful system of the heavenly Bodies; for all nature is exactly the same, the like uniform disposition is every where to be discern'd, the same Ellipses describ'd by Bodies moving round another Body, which is plac'd in one of their Focus's. The Satellites of Jupiter gravitate towards Jupiter, as the Moon gravitates towards the Earth, the Satellites of Saturn towards Saturn, and all the Planets together towards the Sun.

We are ignorant wherein the nature of Gravitation consists, nor was Sir Isaac Newton himself acquainted with it. If Gravitation is caus'd by impulse, we may conceive a piece of falling Marble to be impell'd toward the Earth, without the Earth's having any tendency to move towards the Marble; and in a word, all the Centres, to which the motions arising from Gravitation are directed, may be suppos'd immoveable. But if it acts by Attraction, the Earth cannot attract the piece of Marble, without the reciprocal action of the Marble upon the Earth; for why should any particular Bodies be endued with an attractive power rather than others? Sir Isaac Newton supposes the action of Gravitation to be constantly reciprocal in all Bodies, and proportional only to the quantities of matter contain'd in 'em, and by this means he seems to determine, that Gravitation is in reality an Attraction. 'Tis this word only he makes use of upon all occasions to denote the active force there is in Bodies; a force unknown indeed, and which he does not pretend to define; but if it could also act by impulse, why did he not rather make choice of the clearer expression, since all will allow that they are of too different a nature to be used promiscuously? The perpetual use of the word Attraction, supported by so great an authority, and perhaps also by Sir Isaac Newton's own inclination for the thing itself, at least renders an idea familiar to his readers, which the Cartesians had rejected, and all other Philosophers had condemn'd; we must therefore be upon our guard not to look upon it as a reality, as we are exposed to the temptation of believing that we understand it.

But be this as it will, all Bodies, according to Sir Is. Newton, gravitate towards one another, or attract one another in proportion to the quantities of matter contain'd in 'em; and in revolving about a common Centre, by which they are consequently attracted, and which they mutually attract, their attractive forces vary in a reciprocal proportion of their distances from that Centre; and if all together with their common Centre revolve about another Centre which is common to others with them, new relations must hence arise, which will form a surprising complication. Thus every single Satellite of Saturn gravitates towards the other four, and the other four gravitate towards the fifth; all the five gravitate towards Saturn, and Saturn towards them; they all gravitate towards the Sun, and the Sun towards them all. What an immense skill in Geometry must have been requisite to unravel the intricacies of so many different relations? It seems to have been a bold attempt to have undertaken it; and one cannot without amazement consider, that from so abstracted a Theory, form'd of so many particular Theories, and all of 'em puzzled with difficulties, conclusions should always arise exactly conformable to such facts, as have been establish'd by Astronomy.

Nay farther, upon some occasions, facts, to which Astronomers had not sufficiently attended, seem to have been presag'd by these conclusions. It has been alledg'd for some time past, and especially in England, that when Saturn and Jupiter are in their greatest proximity, tho' then their distance is 165 millions of leagues, their motions are not so regular as in the rest of their course; and Sir Isaac Newton's System at once assigns the reason for it, which no other System but his could ever account for. Jupiter and Saturn do then attract one another with the greater force, because they are nearer to each other, and by this means the regularity of their course is sensibly affected: And even the quantity and bounds of this irregularity are capable of being determin'd.

The Moon is the most irregular of all the heavenly Bodies, the exactest Tables very often fall short of pointing out her course, and we are frequently at a loss to account for the variety of her wanderings. Dr. Halley, whose profound skill in Mathematicks is no hindrance to his being a good Poet, says in the verses he has set before the 3d Edition of Sir Isaac Newton's Principia, that the Moon had not till then been subject to the reins of any Calculation, nor subdued by any Astronomer, but that at last she had submitted to Rule in this new System. All the irregularities of her course are there so necessary, as to become capable of being foretold; and 'tis hardly possible that a System, which so readily accounts for 'em, should not be a just one, if we consider 'em especially as the small part of a whole, in which an infinite number of other appearances are explain'd with the like happy success. The flux and reflux of the Sea seem so naturally to arise from the joint actions of the Sun and Moon upon the Waters, that this once surprising Phænomenon appears now to be no longer wonderful.

The other Theory, upon which the Principia turns, is the doctrine of the Resistance of Fluids to Bodies moving in 'em; and this must necessarily take in some of the principal Phænomena of Nature, such as the motions of the heavenly Bodies, Light, and Sound. Sir Isaac Newton has distinctly examin'd upon geometrical Principles the effects of this resistance arising from the several considerations of the density of the Medium, the velocity of the moving Bodies, and the magnitude of their Surfaces; and has at last drawn conclusions from 'em, which are absolutely inconsistent with the Vortices of Des Cartes, and quite overturn that mighty celestial Pile, which had formerly been lookt upon as impossible to be shaken. If the Planets move round the Sun in any fluid whatsoever, let the ethereal matter which fills up all Space be never so subtle, the Bodies moving in it cannot but demonstrably find some resistance; and if so, whence comes it to pass, that the motions of these Planets are not perpetually and even suddenly impair'd? Or how can the Comets so freely move across these Vortices in directions contrary to the motions of the vortical Fluid, without any sensible alteration in their motions? Or is it possible, that these immense Torrents, moving with an almost incredible rapidity, should not in an instant absorb all the motion of a particular Body, which is but as an Atom in comparison with them, and forcibly carry it along with 'em in their circumvolution?

The heavenly Bodies do therefore move in a void space, except that the Exhalations arising from 'em in conjunction with the Rays of Light, which variously intermix with each other, intersperse a small quantity of matter in the almost infinite portions of immaterial space. The Vacuum and Attraction, which had been banish'd by Des Cartes from the physical World, and to all outward seeming were banish'd for ever, are brought back again by Sir Isaac Newton arm'd with a new force, of which they had been judg'd incapable, and perhaps only a little chang'd in appearance.The two great Men, who are here found in so great an opposition, did in many respects very much resemble each other. They were both of 'em men of a superlative genius, born to command over others, and to lay the foundation of Empires: Both of 'em were excellent Mathematicians, and saw the necessity of introducing Geometry into Physicks; and both of 'em form'd their Systems upon geometrical Reasonings, which they ow'd almost entirely to themselves. But the one was for taking a bold flight, and placing himself at the fountain-head resolv'd to subject even first Principles to certain clear and fundamental Ideas of his own, from whence he would deduce the appearances of Nature as so many consequences from his positions. Whilst the other with more caution and modesty began with observing the operations of Nature, and gradually advancing to unknown principles, with a resolution to admit of such only as might be supplied by a chain of consequences. The one proceeds from what he clearly understands, to find out the cause of what he sees: And the other from what he sees to find out the cause, whether plain or obscure. The evident principles of the one do not always conduct him to appearances such as in reality they are; and appearances do not always lead the other to such principles as are sufficiently evident: Whilst the limits, which in these two opposite methods could put a stop to the farther progress of two such men as these, are not limits of their own, but of human Understanding.

At the same time that Sir Isaac Newton was engag'd upon his great work of the Principia, he had another on his hands, altogether as much an Original as the former; and tho' less general in the title, yet as extensive in the manner he design'd to handle it. 'Tis his Opticks, or Treatise of Light and Colours, which first came abroad in 1704. after the Author had spent 30 years in making the Experiments, he judg'd necessary to compleat it. 'Tis no easy matter to be able to make an Experiment with accuracy. The least fact, which offers itself to our consideration, takes in so many other facts, which modify or compose it, that it requires the utmost dexterity to lay open the several branches of its composition, and no less sagacity to find 'em out. It must be subdivided into other facts, which are themselves compounded; and unless we have at first fallen upon a right method of pursuit, we shall find our selves very often involv'd in unextricable difficulties. Original and elementary facts seem to have been conceal'd from us by nature with as much care as their causes, and when once we come to discover 'em, the view is entirely new, and altogether unforeseen.

The constant object of Sir Isaac Newton's Opticks is the Anatomy of Light. The expression is not too bold, nor more comprehensive than the thing itself. A very small Beam of Light, admitted into a dark room, which yet can never be so small as not to consist of an infinite number of Rays, is divided and dissected, so as to give the elementary Rays, of which it is compos'd, distinct from each other, and differing in colour, which shall after that separation remain unalterable; the whiteness of the undivided beam before its dissection resulting from the intermixture of all the particular colours of the original rays. This separation of rays has been found so difficult, that when Mr. Mariotte attempted it upon the first report of Sir Isaac Newton's Experiments, he fail'd of success, tho' he had so remarkable a genius for making Experiments, and had succeeded so well on so many other occasions.

'Twould have been impossible to have ever separated the primary-colour'd Rays, if they had not been naturally disposed to an inequality of Refraction, in passing thro' the same medium, the same glass prism, and by that means to be disunited, when receiv'd at convenient distances. This different Refrangibility of red, yellow, green, blue, violet, and the vast variety of intermediate-colour'd Rays, a property which had never been suspected, and which no conjecture could ever have form'd, is the fundamental Discovery in Sir Is. Newton's Treatise. From the different Refrangibility we are led to the different Reflexibility; and what is still more curious, the same sort of Rays at equal angles of incidence on any thin transparent plate are alternately reflected and transmitted for many successions; a kind of sport, which could never have been distinguished but by a very good eye, assisted by a very good judgment. And lastly, (in which point only the first thought was not Sir Isaac Newton's) the Rays which pass near the edges of Bodies without touching them, do not pass by them in right lines, but are somewhat turn'd aside, and form that sort of bending which he calls Inflection. From all which observations taken together, he has drawn up a system of Opticks, so perfectly new, that this Science must be always look'd upon hereafter as almost entirely owing to this great Author. 

And, that he might not be wholly confin'd to speculations, which are sometimes unjustly censur'd as mere Amusements, he has farther given us the invention and design of a reflecting Telescope, tho' it was not well executed till some time after. We have seen here, that such a Telescope, of no more than two foot and a half long, has magnified as much as a good common Telescope of eight or nine foot long; a considerable advantage, and such as our posterity will undoubtedly be more sensible of hereafter, than we can be at present.

One benefit arising from this performance, and which may be as momentous as any other branch of knowledge contain'd in it, is, that it supplies us with an excellent model how we should proceed in experimental Philosophy. Whenever we are to search into Nature by Experiments and Observations, we must follow Sir Isaac Newton's example, and act with the same caution and exactness that he has done. He has by a peculiar happiness reduc'd to calculation such matters, as seem'd too nice to be the subject of any enquiry; and to such a calculation, as the greatest skill in Geometry alone could never have effected. The application he has made of his Geometry is as curious, as his Geometry itself is sublime.

He did not finish his Opticks, because he was interrupted in the course of Experiments, which he judg'd necessary, and had not time to take the subject again into his consideration. And 'twill require almost as able hands as the first Architect to compleat the unfinish'd Building. However he has given directions, as much as was possible, to such as should be willing to extend their enquiries farther than he has done, and has even pointed out the way for passing from a Course of Opticks to an entire System of Physicks. Under the form of Queries he proposes a great variety of hints, which may be serviceable to Philosophers hereafter, or will at least contain the first thoughts of a great Philosopher, which will always be an entertainment to the curious.

Attraction is the prevailing principle in this short Abridgment of a System of Physicks. The force in Bodies which we call hardness, is no other than the mutual attraction of their particles, which causes 'em to adhere closely together; and if they are of such a figure, as to touch one another on all sides without leaving any interstices between, they are Bodies perfectly hard. Of this sort only are the primary, unalterable particles, of which all other Bodies are compos'd. Chymical fermentations, or effervescencies, whose motions are sometimes so violent, as not improperly to be compar'd to Hurricanes, are the effects of this powerful attraction, which acts in very small bodies only at very small distances.

In general he is of opinion, that Attraction is the active principle of universal Nature, and the cause which puts all Bodies into motion. For were a certain quantity of motion, originally impress'd upon matter by God Almighty, to be differently distributed according to the known laws of motion, it evidently appears that this motion would be continually decreasing from the contrary impressions of Bodies striking against each other, without any possibility of its being recruited; and thus the Universe would soon fall into a state of inactivity, which would be the general decay of the whole; whilst the power of attraction always subsisting, without any diminution of its force, will constantly furnish a perpetual supply of life and action. Tho' indeed it may so happen, that the particles of matter may enter into such associations thro' the variety of their attractions, that considerable irregularities may be produc'd from thence in the frame of Nature, and this System, according to Sir Isaac Newton's expression, may stand in need of a Reformation. 

He expressly declares, that he does not assign Attraction as a cause that he is able to account for, but only that he considers, compares, and calculates the effects of this principle; and to avoid the imputation of introducing again the occult Qualities of the Schoolmen, he says, that he derives only manifest and very sensible Principles from Phænomena, tho' in reality the causes of those Principles are not yet discover'd, and he leaves 'em to be found out by other Philosophers. But were not the occult Qualities of the Schoolmen Causes, and did they not apparently see the Effects? Or did Sir Isaac Newton believe, that the occult Causes, which he has not been able to discover himself, would be found out by others? Or has he given us any encouragement to enquire after 'em?

He has added at the end of his Opticks two Treatises, which are purely mathematical, the one about squaring curvilinear Figures, and the other entitl'd, Enumeratio Linearum tertii ordinis. He has since omitted 'em, as not belonging to the Subject of his Book; and in 1711. they were printed separately with his Analysis per Quantitatum series, Fluxiones, ac differentias. And I shall only add this remark concerning 'em, that in all these Performances he has discover'd a Genius and Skill in Geometry, which were peculiar only to himself.

A person so entirely given up to speculation may naturally be suppos'd to have been both indifferent towards business, and uncapable to manage it. And yet in the year 1687, the year he publish'd his Principia, when the privileges of the University of Cambridge, where he had been Professor of Mathematicks from the year 1669. by the resignation of Dr. Barrow in his favour, were attack'd by King James II. he was one of the most zealous to maintain 'em, and was accordingly nominated one of the Delegates of the University to the High-Commission Court. He was also chose Member of Parliament in the Convention of 1688. and held his seat there till it was dissolv'd.

In 1696. the Earl of Halifax, Chancellor of the Exchequer, and the great Patron of the Learned (for the English Noblemen don't make a merit of their disregard to Letters, but are often Men of Learning themselves) obtain'd of King William to make Sir Isaac Newton Keeper of the Mint, in which office he did him very signal Services at the time the Money was call'd in to be recoin'd. And about three years after he was advanc'd to be Master of the Mint, an employment of a considerable value, which he held till the day of his death.

'Tis reasonable to suppose, that he was fix'd in this post because of his great skill in Geometry and Natural Philosophy; and indeed 'tis an affair which very often demands both difficult Calculations and a great number of chymical Experiments; and he has given proofs of his Abilities this way in the Table of Assays of foreign Silver, which he printed at the end of Dr. Arbuthnot's Book: 'Tho his Genius cannot but have extended farther, and reach'd even to matters purely political, without any intermixture of speculative knowledge. In 1701. he was again chose Member of Parliament for the University of Cambridge. And perhaps after all it may be a mistake to look upon Learning and Business as so inconsistent with each other, especially in Men of a certain disposition. For political Affairs, if well understood, are naturally reduc'd into certain nice Calculations and Combinations, which minds accustom'd to deep Speculations do more easily and surely comprehend, from the time they are made acquainted with the proper facts, and furnish'd with the necessary materials.

Sir Isaac Newton has had the singular good fortune to enjoy the honours he deserv'd in his own life-time, very different from Des Cartes, who did not receive 'em till after his death The English are not apt to pay the less regard to great Abilities for being of their native growth; but instead of endeavouring to lessen 'em by injurious reflections, or approving the envy which attacks 'em, they all join together in striving to advance 'em; and that excess of Liberty, which divides 'em upon subjects of the greatest importance, is no hindrance to their unanimity in this. They are all sensible that a great Genius must reflect honour upon the State, and whoever is able to procure it to their Country, is upon that account infinitely dear to 'em. All the learned Men of a Nation, which abounds in Men of Learning, plac'd Sir Isaac Newton at their head by a kind of general consent; they acknowledg'd him for their Master and Chief, not a Rebel dar'd to rise up against him, nor did they admit of so much as a cool Admirer. His Philosophy was embrac'd by all England; it prevails in the Royal Society, and in all the excellent productions of its Members, as tho' it had been already consecrated by the veneration of a long succession of Ages. He was reverenc'd in short to so great a degree, that death could not add any new honours to him; he liv'd to see his own Apotheosis. Tacitus, who has reproached the Romans with their extreme indifference towards the great Men of their own Nation, would have given the English the quite contrary commendation. In vain might the Romans have excus'd themselves by urging, that great merit was become familiar to 'em; Tacitus would have answer'd, that great merit was never common, or at least they should, if possible, have endeavour'd to make it so by the glory that should have attended it.

In 1703. Sir Isaac Newton was chosen President of the Royal Society, and continued in the chair for three and twenty years without interruption 'till the day of his death; a single instance; nor did they apprehend they had any reason to fear the consequences. In 1705. he was knighted by Queen Anne, a title of honour, which at least implies, that his name had reach'd as far as the Throne, where the names of the most eminently learned do not always arrive. He was more known at Court than ever under the reign of King George. The Princess of Wales, the present Queen of England, was too well acquainted with his character not to enquire after him, or be satisfied, 'till she had seen him. She has oft been heard to declare in publick, that she thought her self happy in having been born in the same age, and convers'd with him. In how many ages, and how many other countries might he have liv'd, without finding there a Princess of Wales!

He had written a Treatise of antient Chronology, which he did not care to publish, but the Princess, with whom he entrusted the particulars of his design, found 'em so ingenious, that she was desirous to have an abridgment of the whole Work, which was never to go out of her hands, but to be reserv'd only for her private use: And she still keeps it as one of the greatest Treasures she has in her possession. However a Copy of it got abroad, as 'twas natural that a Curiosity rais'd by the expectation of so valuable a fragment of Sir Isaac Newton's, should take all imaginable pains to purchase it; and 'twould be too severe a censure in us, to condemn the attempt. This Copy was brought over into France by the person who was so fortunate as to obtain it, and the esteem he put upon it prevented his keeping it up so closely as might have been desir'd. 'Twas seen, translated, and at last printed.

The principal point in Sir Isaac Newton's Chronology, so far as we are able to collect from the Abridgment, is, by some close reasonings upon the faint remains we have left us of the old Greek Astronomy, to find out the Position of the Equinoctial Colure in the time of Chiron the Centaur with reference to the fix'd Stars. As we are now satisfied that these Stars change their Longitude one degree in about seventy two years, could we once learn thro' what Constellation the Colure pass'd in the time of Chiron, by taking the distance from the present Equinoctial Point, we might be able to find out the number of years which have passed since Chiron's age. Chiron was concern'd in the famous expedition of the Argonauts; and therefore this discovery would fix the Epocha of the Argonautick expedition, and by a necessary consequence the Æra of the Trojan War, upon which two great events all the antient Chronology does entirely depend. And Sir Isaac Newton places 'em five hundred years nearer to the birth of Christ than other Chronologers generally do. This System has been oppos'd by two learned Gentlemen in France, who have been blam'd by the English for having been too forward with their Criticisms, in not having waited till the publication of the entire Work. But this very forwardness has done honour to Sir Isaac Newton. They laid hold of the first opportunity, which could offer 'em the glory of contending with so great an Adversary; and they have found others to rise up in his stead. The learned Dr. Halley, first Astronomer to the King of Great Britain, has already written in defence of the Astronomical part of the System; and his regards for his deceased Friend, and his perfect knowledge of the Subject, must render him a formidable Opponent. The dispute however is not yet ended, the very few who are judges of the affair, have not decided it; and if it should so happen, that the strongest Arguments should lie on one side, and the name of Sir Isaac Newton on the other, the publick, 'tis probable, would remain some time in suspence, and perhaps might be excusable for doing so.

As soon as the Academy of Sciences were impower'd by the regulations which pass'd in 1699, to add foreigners to their Society, they did not fail to make choice of Sir Isaac Newton. He held a constant correspondence with 'em by sending over to 'em whatever he publish'd. These were his former labours, which he either caused to be reprinted, or were then sent abroad for the first time: For after he was employ'd in the Mint, which had been for some years before, he engag'd in no considerable undertaking in Mathematicks or Philosophy. For tho' the solution of the famous Problem about the Trajectoria, which was proposed to the English by M. Leibnitz as a Challenge, during his dispute with them, and had been carefully sought out by him as an intricate and difficult Proposition, might pass for a considerable Production, yet it was no more than a mere Amusement to Sir Isaac Newton. He received the Problem at four in the evening, as he was returning from the Mint fatigued with business, and finish'd the solution before he went to bed. And how, having been so serviceable to all the learned in Europe, by the improvements he had made in speculative knowledge, he gave himself up entirely to the service of his Country by an application to business, that was attended with a more direct and sensible advantage, an employment which must affect every good Citizen with a visible pleasure; but if at any time he had any leisure hours, he would then give way to his curiosity, and thought no scorn of any sort of knowledge, but knew how to reap a benefit from all. There were found amongst his papers abundance of discourses after his death, upon subjects of Antiquity, History, and even Divinity, tho' so remote from the Sciences for which he was distinguish'd. He suffer'd no moment to pass by him idly; nor whilst he was employ'd, could he be content with a slight application.

He liv'd in perfect health, till he was above fourscore years old, a very material circumstance of the singular happiness he enjoy'd. He then began to complain of an involuntary Flux of Urine; tho' for the five years after, which preceded his death, he had great intervals of health or ease, procur'd by the observance of a strict regimen, and cautions he had no need of before. He was oblig'd to rely on Mr. Conduit, who had married his Niece, for the discharge of his office at the Mint; and this he did upon the fullest assurances, that he committed so important a trust to very able hands. His judgment has been confirm'd since his death by the King's choice, who has confer'd the place upon Mr. Conduit. Sir Isaac Newton was a stranger to pain till the last twenty days of his life. 'Twas certainly judged that he had the Stone, and could not possibly be cur'd. And tho' the paroxysms were so violent, that large drops of sweat have run down his cheeks, he was never heard to utter a groan, or give any sign of impatience; and as soon as he had a moment's ease, he would smile, and discourse with his usual cheerfulness. Till this time he had constantly read or wrote several hours every day. He read the News-Papers of Saturday the 18th of March O. S. in the morning, and talk'd a long time with the celebrated Physician Dr. Mead; he was perfectly in his senses, and enjoy'd his understanding to the utmost; but towards evening he lost 'em quite, and never afterwords recover'd 'em; as if the faculties of his Soul had been subject only to a total extinction, and not liable to any decay. He died the Monday following on the 20th of March, in the 86th year of his age.

His body lay in State in the Jerusalem Chamber, from whence persons of the highest rank, and sometimes crown'd Heads have been carried to their graves. He was convey'd from thence into Westminster-Abbey, the Pall being held up by the Lord Chancellor, the Dukes of Montrose and Roxburgh, and the Earls of Pembroke, Sussex and Macclesfield. From these six English Peers, who discharg'd this solemn office, we may form a judgment of the great number of persons of distinction, who must have had a share in the pomp of the Funeral. The Bishop of Rochester read the service, attended by all the Clergy of his Church. The Corps was interr'd near the entrance into the Choir. We must go back almost as far as the antient Greeks, if we would find a like instance of so great a veneration paid to Learning. Sir Isaac Newton's family have farther imitated the example of Greece, by erecting a noble Monument to his memory, upon which they are about to bestow a considerable sum. The Dean and Chapter of Westminster have given leave that it shall be rais'd in a part of the Abbey, which has been refus'd to persons of the first Quality. His Country and Family have paid him the same regards, as if he had made choice of them himself.

He was of a mean Stature, and a little inclin'd to fulness in his later years, of a quick and piercing eye, with a countenance at the same time venerable and engaging, especially when he would throw off his Perruque, and shew his silver Hairs, which hung down in large locks upon his shoulders. He never made use of spectacles, nor lost any more than one single Tooth during his whole life. His name will justify our descending to these minute particulars. He was naturally of a peaceable disposition, and passionately fond of his quiet. He would have rather chose to have lain in obscurity, than to have seen the calm of his life disturb'd by the wranglings and disputes, which are the certain consequences of being eminent. We learn from one of his Letters in the Commercium Epistolicum, that when his Treatise of Opticks was ready for the Press, certain hasty objections, which had been rais'd against it, made him lay aside the design for that time. I blam'd my imprudence, says he, for parting with so valuable a blessing as my quiet, to run after a shadow. But that shadow did not afterwards escape him, nor did it cost him the quiet he so much valued, but prov'd as real an happiness as the quiet itself.

With this disposition we may naturally suppose that he was modest in his deportment; and this character he is said to have always preserv'd without any alteration, tho' the whole world conspir'd against it. He never talk'd either of himself or others, nor ever behav'd in such manner as to give the most malicious observers the least suspicion of his vanity. And tho' the general approbation of mankind might have spar'd him the pains of publishing his own merit, yet how industrious would many others have been to have taken a share in so grateful a task, which most are so unwilling to refer to the judgment of another? How many great men, who have gain'd the applauses of the World, have spoil'd the musick of their praises by running out into their own commendations? He was plain and affable, and open in his dealings with all mankind. Men of the best Understanding do never overlook what's placed below 'em, tho' others are too apt to despise what's plac'd above 'em. He never thought himself discharg'd by his merit or reputation from the common offices of life; nor strove by any singularity, either natural of acquir'd, to distinguish himself from other men.

Tho' he firmly adher'd to the Church of England, he was always averse to the persecution of the Non-Conformists. He judg'd of men by their manners, and the true Non-Conformists with him were the wicked and the vicious. Not that he was addicted only to natural Religion, for he was thoroughly persuaded of the truth of Revelation; and amongst the variety of Authors, which he was continually reading, the Book he had most constantly in his hands was the Bible. The plenty he enjoy'd from a large Patrimony and a considerable Employment, advanc'd by the plainness and frugality of his way of life, gave him a fair opportunity of encreasing his Revenue. He thought it no gift to give by will, and for this reason he left none behind him; tho' he would distribute large sums in his life-time in presents to his Relations, or to persons whom he knew to stand in need of his assistance. The instances of his liberality in this way are neither few nor inconsiderable. When decency requir'd him at any time to launch out into expence and dress, he would never spare for magnificence, but appear always in a manner suitable to the occasion. At all other times he was an utter enemy to pomp and figure, which seems great only to little minds, and reserv'd his income for more important uses. 'Twould indeed have been somewhat extraordinary, that a mind accustom'd to reflection, and train'd up to a course of reasoning, should at the same time have been fond of Shew and in love with Extravagance.

He liv'd always single, and perhaps had no time to think of marriage, deep sunk at first in a severe and constant course of study during the prime of life, and afterwards engag'd in the hurry of a considerable Employment, and it may be so taken up with an intenseness of thought, that he had no vacancy left him in life, nor any occasion for companion at home. He left behind him to the value of two and thirty thousand pounds in sterling, which amounts to seven hundred thousand Livres of French Money. His Competitor Mr. Leibnitz died rich also, but far inferior to him, and with a considerable sum in reversion. [NOTE: See the Hist. of the Royal Acad. for the year 1716. p. 128.] These two extraordinary instances, and both of 'em in Foreigners, seem to deserve our attention.