opaque body, and received her light from the fun, round which fhe moved with the earth in one year, while fhe made a circuit round the earth in one month: these, I fay, have been handed down to us probably from the Chaldeans; at least they are so old, that this or the other age or country can lay no claim to the difcovery of them. England, till the reformation, had very little light or learning in these affairs; what we know of the matter fince, has been owing to late discoveries, or rather recoveries; which, though they prove us to have been in ignorance before, will not with equal certainty prove us to be at the height of knowledge now. THE motion of the earth was not recovered fo foon as the reft, not till Copernicus's time, I think in about the year one thousand five hundred; though they talk of Pythagoras picking it up among the Egyptian priefts; which, even by their own accounts, prevents it being a modern difcovery. However, the good people of Europe were then fo bigotted to the translations of fcripture, that that all Copernicus's mathematics could not bring them over to his philofophy. SEVERAL fchemes were invented to reconcile matters, and make his philosophy lefs contradictory to fcripture; but the earth ftill kept its place, and remained immoveable in the centre. Many indeed of the fort efprits of the age, out of mere love to novelty, and oppofition to scripture, gave their affent immediately, without knowing much of either fide of the question, as is ufual with them in fuch cafes; but ftill the majority stuck by the fcriptures, and the thing lay dormant, till Descartes, a volatile Frenchman, formed it into a philofophical romance; which, from the nature of his countrymen, and the tafte of the times in which he lived, he had hopes would take. He did not pofitively affert the fun to be fixed in the centre, and the earth to move round it, but took the philofophic licence to suppose it, for the more fimple explication of the phenomena of nature. As a plenum and the air had been ge nerally nerally allowed to be the caufe of motion, though they had been very deficient in their account of it; he thought he had hit upon something to fupply former defects; fo retained a plenitude of matter, and framed his vortices for movers. He made ufe of the terms gravity and attraction, but not in the fenfe the Newtonians use them, but for the effects produced by the agency of his fubtile matter. THE fixed ftars he banished out of his fyftem for the fame reafons Sir Ifaac did,; because he knew not of what use they were, and they might do mischief; and so he made them funs to other worlds. Ir is here to be obferved, that the only thing Defcartes had to fet up for a philofopher upon, was his vortices. Sympathy and antipathy, materia fubtilis, fuga vacui, &c. had each had its turn, and was each rejected as infufficient. WE could calculate eclipfes; knew, as before observed, that the moon was a dark body, body, and received her light from the fun; and placed the planets and stars at fuch and fuch distances, as we judged most agreeable to our schemes. The cause of motion was the grand fecret each age had been prying into, and which, every now and then, fome or other boasted he had found out. THIS then is the only thing can be properly called a discovery, if the prefent philofophy has happily found out and afcertained it. Newton, however, had nothing to do but to knock down the vortices, and rife up a philofopher. His genius, we are told, led him to mathematics; and he lanched at once into Kepler and Descartes. By a book of the latter, which he made use of when at college, we find him chiefly taken up with the geometrical part; for in feveral places of the margin is written, Error, not geometrical. BUT what did he give us for movers in the room of the vortices? Why, gravitation What Defcartes had made and attraction. only as effects, he more happily adopted for a caufe. One would have thought, when he rejected this feigned and imaginary matter of Descartes, he should have given us fomething real in its place, and not put us off with empty founds. Inftead of this, he retains the fame laws of motion, projection, and centripetal and centrifugal forces, and makes the attraction of gravity the grand catholicon of his philofophy. Thales first found out attraction, as we are told, from seeing amber draw bits of straw; Kepler talks of the virtus attractiva folis; and Bifhop Wilkins, his contemporary and acquaintance, is full of notions of attraction: fo the thing is no difcovery; only he was the first who (to ufe a certain author's words) formed it into a cobweb of circles and lines to catch flies in. As he found Defcartes had laid his scheme too open by writing in a popular way, he took a method more politic, as well as more fuitable to the bent of his genius. He drew a magic circle round him, in which he intrenched himself and his philosophy, which secured him from any profane foot breaking |