Vidal's major work was the translation of Johann Lorenz Mosheim's Commentaries on the Affairs of the Christians before the Time of Constantine, vols. i. and ii. 1813, vol. iii. 1835. He had antiquarian tastes, and communicated papers on trial by ordeal and on the site of Kenwith Castle, Devonshire, to the Society of Antiquaries of London, through his friend Henry Wansey. He prepared the third edition of A Treatise on Copyholds (London, 1821, 2 vols.) by Charles Watkins, and the fifth edition of the work on Tenures (London, 1824) of Sir Geoffrey Gilbert.[1]