Sir Hans Sloane, a British naturalist, born at Killyleagh, county Down, Ireland, April 16, 1660, died in Chelsea, near London, Jan. 11, 1753. He studied medicine, natural history, and chemistry in London, where he became acquainted with Ray and Boyle. After a tour on the continent, he settled in 1684 in London, and was soon after elected a fellow of the royal society. In 1687 he accompanied the duke of Albemarle to Jamaica in the capacity of physician, and during a residence of 15 months made large collections of natural curiosities, particularly of plants. Returning to London, he was chosen physician of Christ's hospital in 1694, a post which he filled for 36 years. Being shortly before this time elected secretary of the royal society, he revived the "Philosophical Transactions," and until 1712 was editor of the work. Meanwhile he had formed the nucleus of a comprehensive cabinet of curiosities, which it became one of the chief objects of his life to enrich and enlarge, and which in 1702 received a very considerable augmentation by the bequest of the collection of William Courten. In 1716 he was created a baronet, and was appointed physician general to the army, which office ho held till 1727, when he became physician in ordinary to the king.

In 1719 he was elected president of the college of physicians, and in 1727 president of the royal society. In 1741 he removed his library and collections to an estate in Chelsea, purchased in 1720, where he spent the rest of his life in retirement. His collections, amounting to 200 volumes of dried plants and over 30,000 other specimens of natural history, besides a library of 50,000 volumes and 3,566 manuscripts, were by the direction of his will offered to the nation for £20,000, less than a quarter of their real value. The legacy was accepted by parliament, and in its purchase originated the British museum. Among many important benevolent schemes he was engaged in the establishment of a dispensary for providing the poor with medical services and medicines, and of the foundling hospital. He also presented the apothecaries' company with the freehold of their botanic garden, which formed part of his estate at Chelsea. His writings comprise " The Natural History of Jamaica" (2 vols, fol., 1707-'25), a Latin catalogue of the plants of Jamaica, a treatise on sore eyes (once highly esteemed), and contributions to the " Philosophical Transactions." He aided in the introduction of the use of Peruvian bark and other new remedies, and gave a considerable impulse to the practice of inoculation by performing that operation on several of the royal family.