(b. Sandwich, Kent, England, 6 November 1604; d. London, England, 13 October 1689)
Ent was the son of Josias Ent, a merchant from the Low Countries. His early education was at Rotterdam; he then studied at Sidney Sussex College, Cambridge, from 1624 to 1631, obtaining his M.A. in 1631. Shortly afterward he probably settled in Padua as a student of medicine. He obtained the M.D. there in 1636, the event being celebrated by a volume of poems, Laureae Apollinari (Padua, 1636), contributed by his friends—including P. M. Slegel, J. Rhode, and J. Greaves, all of whom became friends and defenders of Harvey.
The rest of Ent’s life was spent in London as a successful and moderate medical practitioner. He rapidly reached a position of esteem among his professional and scientific colleagues. Although he probably had royalist sympathies he was not subject to recriminations during the Cromwellian period. During these years he came into prominence at the College of Physicians, in which he was elected to the most important executive positions, serving as president for seven years between 1670 and 1684. He was married to Sarah Meverall, daughter of the treasurer of the college. The Royal Society provided an outlet for his wider scientific interests; he was a founder fellow and member of its council, although playing a relatively small part in its scientific affairs. Ent was one of the last to give the annual anatomy lectures at the College of Physicians. At these lectures in 1665 he was granted a knighthood by Charles II.
Ent owed much of his scientific reputation to his friendship with William Harvey, which dated from their chance meeting in Rome in 1636. In reaction to the mounting published criticism of De motu cordis, Ent became one of the first writers to compose a detailed defense of Harvey, Apologia pro circulatione sanguinis (1641). This counteracted the criticisms of Emilius Parisianus; Ent quoted primarily from Harvey but also displayed a wide familiarity with ancient and modern authorities. In a series of digressions he showed a distinctive approach, being more receptive to hermetic authors than Harvey. This is particularly obvious in the sections on innate heat and respiration, which point toward the theories of John Mayow and suggest that nitrous particles from the air are absorbed by the lungs or gills, to support the physiological flame burning in the heart-the source of innate heat. Ent further proposed a less fortunate, but popular, theory whereby a highly nutritive fluid is dispensed through the nerves. Accordingly, the nervous role is reduced; Ent emphasized the role of tissue irritability and natural movement. His ideas on irritability are particularly prominent in his unpublished anatomy lecture notes.
Ent’s association with Harvey continued. In about 1648 he persuaded the elderly Harvey to release the manuscript of De generatione, which Ent edited and published with a commendatory preface in 1651. His transcript of Harvey’s correspondence was used in the College of Physicians edition of Harvey’s works in 1766. Harvey’s gratitude was indicated in the terms of his will, in which Ent was charged with dispersing his library, that is, selling worthless books and buying better ones to be deposited, with the rest of the library, in the College of Physicians. Ent was also given five pounds to purchase a ring in remembrance of Harvey.
Ent’s other writings are less important. His proficient studies of the anatomy of Lophius, Galeus, and Rana, entitled “Mantissa anatomica,” were published in one of Charleton’s lesser works. This appears to have been the meager outcome of an elaborate mutual comparative anatomy project, conceived in the 1650’s. Finally, Ent published a critique of Malachi Thruston’s ideas on respiration, which showed little advance on the Apologia and lacked the empirical foundation of Mayow’s writings on the same theme.
I. Original Works. Ent’s writings are Apologia pro circulatione sanguinis: Qua respondetur Aemilio Parisano (London, 1641; 2nd ed., with some additions, 1685); ANTIΔIATPIBH. Sive animadversiones in Malachiae Thrustoni, M.D. Diatribam de respirationis usu primario (London, 1679, 1685); and Opera omnia medico-physica (Leiden, 1687), which contains essays on tides. See also “Mantissa anatomica,“in Walter Charleton, Onomasticon zoicum, 2nd ed. (Oxford, 1677). Ent’s anatomy lectures are in Bodleian Library, Ashmolean MS 1476, and Royal College of Physicians, London, MS 110.
II. Secondary Literature. On Ent’s life and work, see Sir George Clark, History of the Royal College of Physicians, vol. 1 (London, 1964); Sir Geoffrey Keynes, The Life of William Harvey (Oxford, 1966); William Munk, Roll of the Royal College of Physicians, I (London, 1878), 223–227; J. R. Partington, History of Chemistry, II (London, 1962), 564, 573–574; J. and J. A. Venn, Alumni cantabrigenses, II (Cambridge, 1924), 104; and C. Webster, “The College of Physicians ‘Solomon’s House’ in Commonwealth England,” in Bulletin of the History of Medicine, 41 (1967), 393–412.