1801, reached a third edition two years later, and occasioned some controversy. In April 1801 he was nominated by Pitt to a canonry of Westminster. When in the following year (1802) Vincent was offered by Addington the deanery of Westminster, ‘as a public reward for public services,’ this was understood to refer to his recent publication. The see of Rochester was now for the first time for many years severed from the deanery.
In 1805 Vincent obtained the rectory of St. John's, Westminster, and resigned that of All Hallows to his son. In 1807 he exchanged St. John's for the rectory of Islip, Oxfordshire, where he made his country residence. He had been appointed president of Sion College in 1798, and acted as prolocutor of the lower house of convocation in 1802, 1806, and 1807. The fire which broke out in the roof of the lantern of Westminster Abbey on 9 July 1803 necessitated repairs to the fabric. They were all paid for by the dean and chapter; but in 1805 Vincent addressed a letter to Pitt praying for a national grant for the restoration of Henry VII's Chapel. Fourteen annual grants, beginning from 1807, were received, and the work was proceeded with under the direction of Thomas Gayfere and Benjamin Wyatt. The restoration was not completed till 1822. The manner in which it was carried out, especially the interference with the tomb of Thomas of Woodstock, duke of Gloucester, in order to make way for the new Addison monument, was severely criticised in the ‘Gentleman's Magazine’ by John Carter [q. v.], the architect. Vincent replied by the jeux d'esprit ‘Woodstock's Ghost’ and ‘Addison's Ghost,’ satirical verses directed against Carter and William Capon [q. v.], the scene-painter (in Gent. Mag. 1808 ii. 1105–6, 1809 i. 157). Dean Vincent also directed the restoration of the great rose or marigold window; and caused the enormous monuments of Captains Harvey, Hutt, and Montagu (who fell in Howe's victory of 1 June 1794) to be removed from between the pillars of the nave to their present positions. Pitt and Charles James Fox were buried in the abbey in 1806, and the Duc de Montpensier (brother of Louis-Philippe) in Henry VII's Chapel in the following year. Minute accounts of the repairs executed at the abbey and of the chapter business while he was dean are given in a manuscript notebook of Vincent's, which is still preserved at the deanery. The book also contains an account by him of the sixteenth and seventeenth century chapter-books, and an analysis and criticism of Flete's manuscript ‘Chronicle of the Abbey.’
Vincent made his reputation as a classical scholar by the publication of a Latin treatise entitled ‘De Legione Manlianâ Quæstio ex Livio desumta, et rei militaris Romanæ studiosis proposita.’ In this, by means of an ingenious emendation, he reconciled the apparently conflicting statements of Livy and Polybius respecting the legion. Porson and Heyne gave a general assent to his views. Only four copies of the work are said to have been sold. In the next year Vincent published ‘The Origination of the Greek Verb: an Hypothesis,’ followed in 1795 by ‘The Greek Verb Analysed: an Hypothesis in which the Source and Structure of the Greek Language in general is considered.’ He found the reasons for the inflections of the verbs in their derivations from ‘a simple and very short original verb signifying to do or exist,’ which being afterwards subjoined to radicals, denoting various actions and modes of being, formed their tenses, modes, and other variations. Vincent had to defend his work against the charges of insufficient research and plagiarism (from a writer in the ‘Encyclopædia Britannica’), advanced in the ‘Hermes Unmasked’ of Thomas Gunter Browne. His views did not succeed in holding their ground.
But ancient geography was the subject which Vincent made his chief study. In 1797 he issued his commentary on Arrian's ‘Voyage of Nearchus’ (contained in the ‘Indica’), which he terms ‘the first event of general importance to mankind in the history of navigation.’ Schneider, a later editor of Arrian, translated Vincent's arguments into Latin and subjoined them as a complete answer to the objections of Dodwell. Vincent had the assistance of Alexander Dalrymple [q. v.], hydrographer to the admiralty, who prepared charts, and of Samuel Horsley [q. v.], then dean of Westminster, who furnished two astronomical dissertations. The subject was pursued in ‘The Periplus of the Erythræan Sea,’ which appeared in two parts in 1800 and 1805. These three commentaries, which occupied Vincent's leisure during eight years, were dedicated to George III. ‘The Commerce and Navigation of the Ancients in the Indian Ocean,’ 2 vols., issued in 1807, forms a second edition of the whole work. It was dedicated to Lord Sidmouth. It contains contributions by Professor Heyne, Dr. Schneider, and Niebuhr, as well as by Sir Gore Ouseley, Dr. Burney, and William Wales. McCulloch termed it a most valuable contribution to the geography of antiquity and the history of commerce. An English translation of the ‘Voyage of Nearchus’ and of the
