ROBINIA, in botany, a genus of the Diadelphia Decandria class and order. Natural order of Papilionacex, or Legu minosx. Essential character : calyx four cleft ; legume gibbous, elongated. There are seventeen species.
ROBINS (13ExJ.imix), in biography, an English mathematician and philoso pher, of great genius and eminence, was born at Bath, in Somersetshire, 1707. His parents were of low condition, and quakers ; and, consequently, neither able from their circumstances, nor willing from their religious profession, to have him much instructed in that kind of learn ing which they are taught to despise as human. Nevertheless he made an early and surprising progress in various branches of science and literature, par ticularly in the mathematics ; and his friends being desirous that lie might con tinue his pursuits, and that his merit might not be buried in obscurity, wished that he could be properly recommended to teach that science in London. Accord ingly, a specimen of his abilities, in this way, was sent up thither, and shown to Dr. Pemberton, the author of the " View of Sir Isaac Newton's Philosophy ;" who thence conceiving a good opinion of the writer, for a further trial of his skill, sent him some problems, which Robins re solved very much to his satisfaction. He then came to London, where he confirm ed the opinion which had been precon ceived of his abilities and knowledge.
But though Robins was possessed of much more skill than is usually required in a common teacher ; yet being very young, it was thought proper that he should employ some time in perusing the best writers upon the sublimer parts of the mathematics, before he should under take publicly the instruction of others. In this interval, besides improving him self in the modern languages, he bad op portunities of reading, in particular, the works of Archimedes, Apollonius, Fer mat, Huygens, De Witt, Slusius, Grego ry, Barrow, Newton, Taylor and Cotes. These authors he readily understood, without any assistance, of which he gave frequent proofs to his friends : one was, a demonstration of the last proposition of " Newton's Treatise on Quadratures," which was thought not undeserving a place in the Philos. Trans. fbr 1727.
Not long after an opportunity offered him of exhibiting to the public a specimen also of his knowledge in natural philoso phy. The Royal Academy of Sciences
at Paris had proposed, among their prize questions in 1724 and 1726, to demon strate the laws of motion in bodies im pinging on one another. John Bernoulli here condescended to be a candidate ; and as his dissertation lost the reward, he ap pealed to the learned world by printing it in 1727. In this piece he endeavoured to establish Leibnitz's opinion of the force of bodies in motion, from the effects of their striking against springy materials : as Po leni had before attempted to evince the same thing, from experiments of bodies falling on soft and yielding substances. But as the insufficiency of Poleni's argu ments had been demonstrated in the Phi los. Trans. for 1722; so Robins published in the " Present State of the Republic of Letters," for May 1728, a confutation of Bernoulli's performance, which was al lowed to be unanswerable.
Robins now began to take scholars. About this time he quitted the dress and profession of a quaker and, probably, without reflecting very much upon the subject of religion, he soon shook off the prejudices of his early habits. But though he professed to teach the ma thematics only, he would frequently as sist particular friends in other matters ; for he was a man of universal knowledge; and the confinement of this way of life not suiting his disposition, which was active, he gradually declined it, and went into other courses that required more exer cise Hence he tried many laborious ex periments in gunnery ; believing that the resistance of the air had a much greater effect on swift projectiles than was gene rally supposed. And hence he was led to consider those mechanic arts that de pend upon mathematical principles, in which he might employ his invention ; as the constructing of mills, the building of bridges, draining of fens, rendering of ri vers navigable, and making of harbours. Among other arts of this kind, fortifica tion very much engaged his attention ; in which he met with opportunities of per fecting himself; by a view of the principal strong places of Flanders, in some jour nies he made abroad with persons of dia.. tinction.