and later by a French tutor named Marcombes. With him and his elder brother Francis he left England in October 1638, and, passing through Paris and Lyons, settled during twenty-one months at Geneva, where he acquired the gentlemanly accomplishments of fluent French, dancing, fencing, and tennis-playing. From this time, when he was about fourteen, he dated his 'conversion,' or that express dedication to religion from which he never afterwards varied. The immediate occasion of this momentous resolve was the awe inspired by a thunderstorm.
At Florence during the winter of 1641-2 he mastered Italian, and studied 'the new paradoxes of the great star-gazer Galileo,' whose death occurred during his stay (8 Jan. 1642). He chose in Rome to pass for a Frenchman, and with the arrival of the party at Marseilles, about May 1642, Boyle's record of his early years abruptly closes. A serious embarrassment here awaited them. A sum of 250l., with difficulty raised by Lord Cork during the calamities of the Irish rebellion, was embezzled in course of transmission to his sons. Almost penniless, they made their way to Geneva, M. Marcombes' native place, and there lived on credit for two years. At length, by the sale of some jewels, they raised money to defray their expenses homewards, and reached England in the summer of 1644. They found their father dead, and the country in such confusion that it was nearly four months before Robert Boyle, who had inherited the manor of Stalbridge, could make his way thither.
But civil distractions were powerless to extinguish scientific zeal. From the meetings in London in 1645 of the 'Philosophical,' or (as he preferred to call it) the 'Invisible College,' incorporated, after the Restoration, as the Royal Society, Boyle derived a definitive impulse towards experimental inquiries. He was then a lad of eighteen, but rose rapidly to be the acknowledged leader of the movement thus originated. Chemistry was from the first his favourite study. 'Vulcan has so transported and bewitched me,' he wrote from Stalbridge to his sister, Lady Ranelagh, 31 Aug. 1649, as to 'make me fancy my laboratory a kind of Elysium.' Compelled to visit his disordered Irish estates in 1652 and 1653, he described his native land as 'a barbarous country, where chemical spirits were so misunderstood, and chemical instruments so unprocurable, that it was hard to have any Hermetic thoughts in it.' Aided by Sir William Petty, he accordingly practised instead anatomical dissection, and satisfied himself experimentally as to the circulation of the blood. On his return to England in June 1654 he settled at Oxford in the society of some of his earlier philosophical associates, and others of the same stamp, including Wallis and Wren, Goddard, Wilkins, and Seth Ward. Meetings were alternately held in the rooms of the warden of Wadham (Wilkins) and at Boyle's lodgings, adjoining University College, and experiments were zealously made and freely communicated. Boyle erected a laboratory, kept a number of operators at work, and engaged Robert Hooke as his chemical assistant. Reading in 1657, in Schott's 'Mechanica hydraulico-pneumatica,' of Guericke's invention for exhausting the air in a closed vessel, he set Hooke to contrive a method less clumsy, and the result was the so-called 'machina Boyleana,' completed towards 1659, and presenting all the essential qualities of the modern air-pump. By a multitude of experiments performed with it, Boyle vividly illustrated the effects (at that time very imperfectly recognised) of the elasticity, compressibility, and weight of the air; investigated its function in respiration, combustion, and the conveyance of sound, and exploded the obscure notion of a fuga vacui. A first instalment of results was published at Oxford in 1660, with the title, 'New Experiments Physico-Mechanical touching the Spring of the Air and its Effects, made, for the most part, in a new Pneumatical Engine.' His 'Defence against Linus,' appended, with his answer to the objections of Hobbes, to the second edition (1662), contained experimental proof of the proportional relation between elasticity and pressure, still known as 'Boyle's Law' (Works, folio ed. 1744, i. 100). This approximately true principle, although but loosely demonstrated, was at once generalised and accepted, and was confirmed by Mariotte in 1676.
Boyle meanwhile bestowed upon theological subjects attention as earnest as if it had been undivided. At the age of twenty-one he had already written, besides a treatise on ethics, several moral and religious essays, afterwards published. His veneration for the Scriptures induced him, although by nature averse to linguistic studies, to learn Hebrew and Greek, Chaldee and Syriac enough to read them in the originals. At Oxford he made some further progress in this direction,with assistance from Hyde, Pococke, and Clarke; applied himself to divinity under Barlow (afterwards bishop of Lincoln); and encouraged the writings on casuistry of Dr. Robert Sanderson with a pension of 50l. a year. Throughout his life he was a munificent supporter of projects for the diffusion of the Scriptures. He bore wholly, or in