tacked by an illness thought to be consumption, and this led to his extraordinary abilities being brought to the notice of Richard Brocklesby (1722–1797) [q. v.], an uncle of his mother, who was called in and succeeded in restoring him to health. From this period he visited Brocklesby in London each winter, and at his house met with most of the distinguished literary men of the day, and when eighteen was recognised by them as a classical scholar of no mean order.
In 1792 Young took lodgings in Little Queen Street, Westminster, and commenced studying for the medical profession. He first attended the lectures of Matthew Baillie [q. v.], William Cumberland Cruikshank [q. v.], and John Hunter (1728–1793) [q. v.], and then, in 1793, entered for a year as a student at St. Bartholomew's Hospital. On 30 May 1793 he read a paper before the Royal Society, in which he attributed the accommodating power of the eye to a muscular structure of the crystalline lens. This was published in the ‘Philosophical Transactions’ of the society, and led to his election, on 19 June 1794, as a member of the society. In the autumn of that year he proceeded to Edinburgh, where it had been decided he should continue his studies, and spent the winter there, attending lectures by James Gregory (1753–1821) [q. v.], Andrew Duncan [q. v.], and Joseph Black [q. v.], and studying German, Spanish, and Italian. During this time he dropped the outward characteristics of a ‘Friend,’ mixed largely in society, to which his uncle's position and his own reputation gave him an entrance, and learnt to play the flute, to sing, and to dance. In the summer of 1795 he made a tour of the highlands, in the course of which he visited the Duke of Gordon at Elgin, and the Duke of Argyll at Inverary. In October he went to Göttingen, to continue his studies under Arnemann, Richter, Blumenbach, and Lichtenberg. There he learnt horsemanship and devoted considerable attention to music and art. On 30 April he passed the examination, and his dissertation ‘De Corporis Humani viribus conservatricibus’ having been approved, he was created doctor of physic on 16 July 1796. Leaving Göttingen a few weeks later, he travelled mainly on foot to Dresden, where he remained a month to study the art collection, and then continued his journey by Berlin and Hamburg to London.
In accordance with the wishes of Brocklesby he entered as a fellow-commoner at Emmanuel College, Cambridge, on 18 March 1797. The Rev. Robert Towerson Cory, shortly afterwards master of the college, was one of his tutors, but he was never required to attend the common duties of the college. He was known as ‘Phenomenon Young,’ and associated on terms of equality with the fellows, but complained of the barriers which custom imposed on his free intercourse as a student with the more distinguished members of the university. On the sudden death of Brocklesby, on 13 Dec. 1797, he succeeded to his uncle's house in Norfolk Street, Park Lane, London, his library, pictures, and 10,000l. He continued, however, to reside at Cambridge in term time, entered as much as possible into general society, and formed friendships with many distinguished scholars, e.g. (Sir) William Gell [q. v.], Edward Dodwell [q. v.], Matthew Raine [q. v.], (Sir) Isaac Pennington [q. v.], and John Cust (Earl Brownlow) (1779–1853), which he retained in after life. In the summer of 1798 he carried out some experiments on sound and light, afterwards communicated to the Royal Society, which formed the starting-point for his subsequent theory of ‘interference.’ After spending part of 1799 in attending the London hospitals, he established himself in practice as a physician at 48 Welbeck Street, London. He continued, however, his contributions to literature and science, sometimes under his own name, sometimes anonymously, to avoid the charge of allowing other studies to take his attention from the duties of his profession.
In July 1801 he was appointed professor of natural philosophy at the Royal Institution, editor of the ‘Journals,’ and superintendent of the house, with a salary of 300l. and rooms. Between January and May 1802 he delivered thirty-one, and next year sixty lectures, which he afterwards (1807) published. His lectures displayed the extraordinary width of his acquaintance with his subjects, but were too didactic and condensed for the popular audiences to whom they were delivered (Paris). He resigned the professorship in July 1803, as his friends considered the duties interfered with his prospects as a physician. In 1802 he was appointed foreign secretary to the Royal Society, and held that office till his death. In March 1803 he was admitted at Cambridge to the degree of M.B., and on 2 July 1808 took the degree of M.D.
The summer of 1805 was spent professionally at Worthing, then a fashionable watering-place, and the visit was repeated annually till 1820, Young having in 1808 acquired a house there.
He became a candidate of the College of Physicians on 30 Sept. 1808 and fellow on 22 Dec. 1809. He was censor in 1813 and
