Boyle, Hon. Robert 1627-1691, natural philosopher and chemist, was the seventh son and fourteenth child of Richard Boyle, the great Earl of Cork, by his second wife Catherine, daughter of Sir Geoffrey Fenton, principal secretary of state for Ireland, and was born at Lismore Castle, in the province of Munster, Ireland, on 25 Jan. 1627. He learned early to speak Latin and French, and won paternal predilection by his aptitude for study, strict veracity, and serious turn of mind. His mother died when he was three years old, and at the age of eight he was sent to Eton, the provost then being his father's friend, Sir Henry Wotton, described by Boyle as not only a fine gentleman himself, but very well skilled in the art of making others so. Here an accidental perusal of Quintus Curtius conjured up in him (he narrates in an autobiographical fragment) that unsatisfied appetite for knowledge that is yet as greedy as when it first was raised; while Amadis de Gaule, which fell into his hands during his recovery from a fit of tertian ague, produced an unsettling effect, counteracted by a severe discipline—self-imposed by a boy under ten—of mental arithmetic and algebra.
     From Eton, after nearly four years, he was transferred to his father's recently purchased estate of Stalbridge, in Dorsetshire, and his education continued by the Rev. Mr. Douch, 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 part, the expense of printing the Indian, Irish, and Welsh Bibles (1685-86); of the Turkish New Testament, and of the Malayan version of the Gospels and Acts (Oxford, 1677). As governor of the Corporation for the Spread of the Gospel in New England, and as director of the East India Company (the charter of which he was instrumental in procuring), he made strenuous efforts, and gave liberal pecuniary aid towards the spread of christianity in those regions. He contributed, moreover, largely to the publication of Burnet's History of the Reformation, bestowed a splendid reward upon Pococke for his translation into Arabic of Grotius' De Veritate, and during some time spent 1,000l. a year in private charity. Nor was science forgotten. Besides his heavy regular outlay, and help afforded to indigent savants, we hear in 1657, in a letter from Oldenburg, of a scheme for investing 12,000l. in forfeited Irish estates, the proceeds to be devoted to the advancement of learning; and a looked-for increase to his fortunes in 1662 should have been similarly applied, but that, being cast upon impropriations, he felt bound to consecrate it to religious uses.
     On the Restoration, he was solicited by the Earl of Clarendon to take orders; but excused himself, on the grounds of the absence of an inner call, and of his persuasion that arguments in favour of religion came with more force from one not professionally pledged to uphold it. This determination involved the refusal of the provostship of Eton, offered to him in 1665. He also repeatedly declined a peerage, and died the only untitled member of his large family.
     In 1668 he left Oxford for London, and resided until his death in Lady Ranelagh's house in Pall Mall. The meetings of the Royal Society perhaps furnished in part the inducement to this move. Boyle might be called the representative member of this distinguished body. He had taken a leading part in its foundation; he sat on its first council; the description and display of his ingenious experiments gave interest to its proceedings; he was elected its president 30 Nov. 1680, but declined to act from a scruple about the oaths, and was replaced by Wren. His voluminous writings flowed from him in an unfailing stream from 1660 to 1691, and procured him an immense reputation, both at home and abroad. Most of them appeared in Latin, as well as in English, and were more than once separately reprinted. In the Sceptical Chymist (Oxford, 1661) he virtually demolished, together with the peripatetic doctrine of the four elements, the Spagyristic doctrine of the tria prima, tentatively substituting the principles of a mechanical philosophy, expounded in detail in his Origin of Forms and Qualities (1666). Founded on the old atomic hypothesis, these accord, in the main, with the views of many recent physicists. They postulate one universal kind of matter, admit in the construction of the visible world only moving atoms, and derive diversity of substance from their various modes of grouping and manners of movement. Boyle added as a corollary the transmutability of differing forms of matter by the rearrangement of their particles effected through the agency of fire or otherwise; referred sensible qualities to the action of variously constituted particles on the human frame, and declared, in the obscure phraseology of the time, that the grand efficient of forms is local motion (Works, ii. 483). He acquiesced in, rather than accepted, the corpuscular theory of light, but clearly recognised in heat the results of a brisk molecular agitation (ibid. i. 282).
     In Experiments and Considerations touching Colours (1663) he described for the first time the iridescence of metallic films and soap-bubbles; in Hydrostatical Paradoxes (1666) he enforced, by numerous and striking experiments (presented to the Royal Society in May 1664), the laws of fluid equilibrium. His statement concerning the Incalescence of Quicksilver with Gold (Phil. Trans. 21 Feb. 1676) drew the serious attention of Newton (see his letter to Oldenburg in Boyle's Works, v. 396), and a widespread sensation was created by his Historical Account of a Degradation of Gold (1678), the interest of both these pseudo-observations being derived from their supposed connection with alchemistic transformations. Boyle's faith in their possibility was further evidenced by the repeal, procured through his influence in 1689, of the statute 5 Henry IV against multiplying gold.
     Amongst Boyle's numerous correspondents were Newton, Locke, Aubrey, Evelyn, Oldenburg, Wallis, Beale, and Hartlib. To him Evelyn unfolded, 3 Sept. 1659, his scheme for the foundation of a physico-mathematic college, and Newton, 28 Feb. 1679, his ideas regarding the qualities of the æther. Nathaniel Highmore dedicated to him in 1651 his History of Generation; Wallis in 1659 his essay on the Cycloid; Sydenham in 1666 his Methodus curandi Febres, intimating Boyle's frequent association with him in his visits to his patients; and Burnet addressed to him in 1686 the letters constituting his Travels. Wholesale plagiarism and theft formed a vexatious, though no less flattering, tribute to his fame. Hence the Advertisement about the loss of many of his Writings, published in May 1688, in which he described the various mischances, both by fraud and accident, having befallen them, and declared his intention to write thenceforth on loose sheets, as offering less temptation to thieves than bulky packets, and to send to press without the dangerous delays of prolonged revision. In the same year he gave to the world A Disquisition concerning the Final Causes of Natural Things, and in 1690 Medicina Hydrostatica and The Christian Virtuoso, setting forth the mutual serviceableness of science and religion. The last work published by himself was entitled Experimenta et Observationes Physicæ, part i. (1691); the second part never appeared.
     In 1689 the failing state of his health compelled him to suspend communications to the Royal Society, and to resign his post, filled since 1661, as governor of the Corporation for the Spread of the Gospel in New England. About the same time he publicly notified his intention of excluding visitors on certain portions of four days in each week, thus reserving leisure to recruit (as he said) his spirits, to range his papers, and to take some care of his affairs in Ireland, which are very much disordered, and have their face often changed by the public calamities there. He was also desirous to complete a collection of elaborate chemical processes, which he is said to have entrusted to a friend as a kind of Hermetick legacy, but which were never made known. Some secrets discovered by him, such as the preparation of subtle poisons and of a liquid for discharging writing, he concealed as mischievous.
     From the age of twenty-one he had suffered from a torturing malady, of which he dreaded the aggravation, with the approach of death, beyond his powers of patient endurance. But his end was without pain, and almost without serious illness. His beloved sister, Catherine Lady Ranelagh, a conspicuous and noble personage, died 23 Dec. 1691. He survived her one week, expiring three-quarters of an hour after midnight, 30 Dec., aged nearly 65, and was buried 7 Jan. 1692 in St. Martin's-in-the-Fields, Westminster. Dr. Burnet preached his funeral sermon. By his will he founded and endowed with 50l. a year the Boyle Lectures, for the defence of Christianity against unbelievers, of which the first set of eight discourses was preached by Bentley in 1692.
     Mr. Boyle, Dr. Birch writes (Life, p. 86), was tall of stature, but slender, and his countenance pale and emaciated. His constitution was so tender and delicate that he had divers sorts of cloaks to put on when he went abroad, according to the temperature of the air, and in this he governed himself by his thermometer. He escaped, indeed, the small-pox during his life, but for almost forty years he laboured under such a feebleness of body and lowness of strength and spirits that it was astonishing how he could read, meditate, try experiments, and write as he did. He had likewise a weakness in his eyes, which made him very tender of them, and extremely apprehensive of such distempers as might affect them. To these disabilities was added that of a memory so treacherous (by his own account) that he was often tempted to abandon study in despair. He spoke with a slight hesitation; nevertheless at times distinguished himself by so copious and lively a flow of wit that Mr. Cowley and Sir William Davenant both thought him equal in that respect to the most celebrated geniuses of that age. He never married, but Evelyn was credibly informed that he had paid court in his youth to the Earl of Monmouth's beautiful daughter, and that his passion inspired the essay on Seraphic Love, published in 1660. It was, however, already written in 1648, and Boyle himself assures us, 6 Aug. of that year, that he hath never yet been hurt by Cupid (Works, i. 155). The story is thus certainly apocryphal.
     The tenor of his life was in no way inconsistent with his professions of piety. It was simple and unpretending, stainless yet not austere, humble without affectation. His temper, naturally choleric, he gradually subdued to mildness; his religious principles were equally removed from laxity and intolerance, and he was a declared foe to persecution. He shared, indeed, in some degree the credulousness of his age. He publicly subscribed to the truth of the stories about the demon of Mascon, and vouched for the spurious cures of Greatrakes the stroker. Nor did he wholly escape the narrowness inseparable from the cultivation of a philosophy that valued no knowledge but as it had a tendency to use. His view of astronomical studies is, in this respect, characteristic. If the planets have no physical influence on the earth, he admits his inability to propound any end for the pains bestowed upon them; we know them only to know them (ibid. v. 124).
     Yet his services to science were unique. The condition of his birth, the elevation of his character, the unflagging enthusiasm of his researches, combined to lend dignity and currency to their results. These were coextensive with the whole range, then accessible, of experimental investigation. He personified, it might be said, in a manner at once impressive and conciliatory, the victorious revolt against scientific dogmatism then in progress. Hence his unrivalled popularity and privileged position, which even the most rancorous felt compelled to respect. No stranger of note visited England without seeking an interview, which he regarded it as an obligation of christian charity to grant. Three successive kings of England conversed familiarly with him, and he was considered to have inherited, nay outshone, the fame of the great Verulam. The excellent Mr. Boyle, Hughes wrote in the Spectator (No. 554), was the person who seems to have been designed by nature to succeed to the labours and inquiries of that extraordinary genius. By innumerable experiments he, in a great measure, filled up those plans and outlines of science which his predecessor had sketched out. Addison styled him (No. 531) an honour to his country, and a more diligent as well as successful inquirer into the works of nature than any other one nation has ever produced. To him, Boerhaave wrote, we owe the secrets of fire, air, water, animals, vegetables, fossils; so that from his works may be deduced the whole system of natural knowledge (Methodus discendi Artem Medicam, p. 152).
     It must be admitted that Boyle's achievements are scarcely commensurate to praises of which these are but a sample. His name is identified with no great discovery; he pursued no subject far beyond the merely illustrative stage; his performance supplied a general introduction to modern science rather than entered into the body of the work. But such an introduction was indispensable, and was admirably executed. It implied an advance all along the line. Subjects of inquiry were suggested, stripped of manifold obscurities, and set in approximately true mutual relations. Above all, the fruitfulness of the experimental method was vividly exhibited, and its use rendered easy and familiar. Boyle was the true precursor of the modern chemist. Besides clearing away a jungle of perplexed notions, he collected a number of highly suggestive facts and observations. He was the first to distinguish definitely a mixture from a compound; with him originated the definition of an element as a hitherto undecomposed constituent of a compound; he introduced the use of vegetable colour-tests of acidity and alkalinity. From a bare hint as to the method of preparing phosphorus (discovered by Brandt in 1669) he arrived at it independently, communicated it 14 Oct. 1680 in a sealed packet to the Royal Society, and published it for the first time in 1682 (Works, iv. 37). In a tract printed the same year he accurately described the qualities of the new substance under the title of the Icy Noctiluca. He, moreover, actually prepared hydrogen, and collected it in a receiver placed over water, but failed to distinguish it from what he called air generated de novo (ibid. i. 35).
     In physics, besides the great merit of having rendered the air-pump available for experiment and discovered the law of gaseous elasticity, he invented a compressed-air pump, and directed the construction of the first hermetically sealed thermometers made in England. He sought to measure the expansive force of freezing water, first used freezing mixtures, observed the effects of atmospheric pressure on ebullition, added considerably to the store of facts collected about electricity and magnetism, determined the specific gravities and refractive powers of various substances, and made a notable attempt to weigh light. He further ascertained the unvarying high temperature of human blood, and performed a variety of curious experiments on respiration. He aimed at being the disciple only of nature. Down to 1657 he purposely refrained from seriously or orderly reading the works of Gassendi, Descartes, or so much as Sir F. Bacon's Novum Organum, in order not to be possessed with any theory or principles till he had found what things themselves should induce him to think (ibid. 194). And, although he professed a special reverence for Descartes, as the true author of the tenets of mechanical philosophy (ibid. iv. 521), we find, nine years later, that he had not yet carried out his intention of thoroughly studying his writings (ibid. ii. 458). Yet he was no true Cartesian; the whole course of his scientific efforts bore the broad Baconian stamp; nor was the general voice widely in error which declared him to have (at least in part) executed what Verulam designed.
     The style of his writings, which had the character rather of occasional essays than of systematic treatises, is free from rhetorical affectations; it is lucid, fluent, but intolerably prolix, its not rare felicities of phrase being, as it were, smothered in verbosity. He endeavoured to remedy this defect by processes of compulsory concentration. Boulton's first epitome of his writings appeared in 1699-1700 (London, 3 vols. 8vo); a second, of his theological works, in 1715 (3 vols. 8vo); and Dr. Peter Shaw's abridgment of his philosophical works in 1725 (3 vols. 8vo). The first complete edition of his writings was published by Birch in 1744 in five folio volumes (2nd edition in 6 vols. 4to, London, 1772). It included his posthumous remains and correspondence, with a life of the author founded on materials collected with abortive biographical designs by Burnet and Wotton, and embracing Boyle's unfinished narrative of his early years entitled An Account of Philaretus during his Minority. More or less complete Latin editions of his works were issued at Geneva in 1677, 1680, and 1714; at Cologne in 1680-95; and at Venice in 1695. A French collection, with the title Recueil d'Expériences, appeared at Paris in 1679. Of his separate treatises the following, besides those already mentioned, deserve to be particularised: 1. Some Considerations touching the Usefulness of Experimental Natural Philosophy (Oxford, 1663, 2nd part 1671). 2. Some Considerations touching the Style of the Holy Scriptures (1663), extracted from an Essay on Scripture, begun 1652, and published, after the writer's death, by Sir Peter Pett. 3. Occasional Reflections upon several Subjects (1664, reprinted 1808), an early production satirised by Butler in his Occasional Reflection on Dr. Charlton's feeling a Dog's Pulse at Gresham College, and by Swift in his Meditation on a Broom Stick, who nevertheless was probably indebted for the first idea of Gulliver's Travels to one of the little pieces thus caricatured (Upon the Eating of Oysters, Works, ii. 219). 4. New Experiments and Observations touching Cold, or an Experimental History of Cold begun (1665), containing a refutation of the vulgar doctrine of antiperistasis (in full credit with Bacon) and of Hobbes's theory of cold. 5. A Continuation of New Experiments Physico-Mechanical touching the Spring and Weight of the Air and their Effects (1669, a third series appeared in 1682). 6. Tracts about the Cosmical Qualities of Things (1670). 7. An Essay about the Origin and Virtues of Gems (1672). 8. The Excellency of Theology compared with Natural Philosophy (1673). 9. Some Considerations about the Reconcilableness of Reason and Religion (1675). 10. The Aerial Noctiluca (1680). 11. Memoirs for the Natural History of Human Blood (1684). 12. Of the High Veneration Man's Intellect owes to God (1685). 13. A Free Enquiry into the vulgarly received Notion of Nature (1686). 14. The General History of the Air designed and begun (1692). 15. Medicinal Experiments (1692, 3rd vol. 1698), both posthumous.
     Catalogues of Boyle's works were published at London in 1688 and subsequent years. He bequeathed his mineralogical collections to the Royal Society, and his portrait by Kerseboom, the property of the same body, formed part of the National Portrait Exhibition in 1866.

     Life by Birch
     Biog. Brit.
     Wood's Fasti Oxon. (Bliss), ii. 286
     Burnet's Funeral Sermon
     Watt's Bibl. Brit.
     Hoefer's Hist. de la Chimie, ii. 155
     Poggendorff's Gesch. d. Physik, p. 466
     Libes's Hist. Phil. des Progrès de la Physique, ii. 134
     A. Crum Brown's Development of the Idea of Chemical Composition, pp. 9-14.

Contributor: A. M. C. [Agnes Mary Clerke]

Published: 1885