land. In America Key had devoted part of his leisure to the etymological study of Latin (Trent, ‘English Culture in Virginia,’ in Johns Hopkins Univ. Studies, 7th ser. vols. v–vi., 1889; H. B. Adams, ‘T. Jefferson and the Univ. of Virginia,’ in No. 2 of U.S. Bureau of Education Circular of Information,’ Washington, 1888). In the autumn of 1828 Key was appointed professor of Latin at the newly founded London University in Gower Street (now University College). In 1842 he resigned this professorship for that of comparative grammar, discharging the duties of the latter chair without salary until his death. In 1833 he had been appointed, jointly with Professor Henry Malden (his contemporary at St. John's College), head-master of the new school attached to University College. From 1842 till his death Key was sole head-master. Between 1868 and 1875 the numbers of the school rose from about four hundred to over six hundred. As a schoolmaster Key was a man of ideas. He introduced the crude-form system of teaching the classical languages, and his school was one of the first in England to include natural science in the ordinary curriculum. Key maintained the discipline firmly but without severity. He died of bronchitis, after a fortnight's illness, on 29 Nov. 1875, and was buried in Highgate cemetery. He married, on 28 Sept. 1824, Sarah Troward, younger daughter of Richard Ironmonger Troward, who had been solicitor to the prosecution in the Warren Hastings trial. Key's wife and seven children survived him.
Key was an enthusiastic and widely read Latin scholar, and had especially a minute acquaintance with Plautus and Terence. His best-known work is his ‘Latin Grammar’ (published in 1846), a book ‘recommended’ (says Mr. Robinson Ellis) ‘by its simplicity, the newness of its examples, and the clearness with which it presents the elementary or crude forms of Latin words apart from their inflexions.’ In January 1831, in reviewing Zumpt's ‘Latin Grammar’ (Quarterly Journal of Education), Key had made the first proposal in print to apply the method of the Sanskrit grammarians to the study and teaching of Latin and Greek, but previously to 1831 the crude-form system had been expounded in his classical lectures. An account of the system is given in Appendix i. in the second and third editions of the ‘Latin Grammar.’ About 1846 Key had begun to prepare a Latin dictionary for schools; but he abandoned this work, and about 1856 undertook a large dictionary, the manuscript of which, left incomplete at his death, was published without additions in 1888 by the syndics of the Cambridge University Press. The letter A is tolerably complete, but only portions of the remaining letters are finished. The work displays wide reading and originality, though the etymologies have been partly superseded by later philological knowledge (see Academy, Saturday Review, and Spectator, all of 5 May 1888; Athenæum, 21 Sept. 1889). Key's chief works are:
- ‘The Alphabet,’ &c. (partly a reprint of his articles from the ‘Penny Cyclopædia,’ 1833–43), London, 1844, 12mo; 2nd edition, 1849.
- ‘The Controversy about the “Varronianus”’ (between Key and J. W. Donaldson, five pamphlets reprinted), London, 1845, 8vo, privately printed.
- ‘A Latin Grammar on the System of Crude Forms,’ London, 1846, 12mo; 2nd edition, London, 1858, 8vo; 3rd edition, 1862, 8vo.
- ‘A Short Latin Grammar,’ London, 1852, 12mo.
- ‘Philological Essays,’ London, 1868, 8vo (partly incorporating papers contributed by Key to the Philological Society).
- ‘Cæsar's Helvetic War,’ with translation and notes, pt. i. cc. 1–29, 1872.
- ‘Language, its Origin and Development,’ London, 1874, 8vo.
- ‘A Latin-English Dictionary,’ Cambridge, 1888, 4to.
Key was a fellow of the Royal Society (elected 1860), and for some years president of the Philological Society of London, to whose ‘Transactions’ he contributed more than sixty-three papers. He was one of the founders of the London Library, and for some years a member of the committee of the Society for the Diffusion of Useful Knowledge. For the atlas of this society he prepared the maps of ‘Gallia’ and ‘France in Provinces,’ and was a contributor to its ‘Quarterly Journal of Education,’ 1831–2. As a politician, Key was a zealous supporter of the Reform Bill, of the repeal of the corn laws, and of the abolition of the paper duty. He also took an active part in the movement which resulted in the formation of the volunteer force in 1859.
A marble bust of Key by T. Woolner, R.A., subscribed for by old pupils and friends as a testimonial a few months before his death, was presented to University College. Key was tall, and of striking personal appearance. Professor George Long, his contemporary at Trinity College and his intimate friend through life, speaks of him as a man of kindly temperament, unaffected and modest, though bold in his opinions, and as ‘a teacher beloved by his pupils.’