The following is the entry for John Tudor in William O'Byrnes 1849 'Naval Biographical Dictionary'.
TUDOR. (Commander, 1842.)John Tudor entered the Navy 6 March, 1813; passed his examination in 1819; and was made Lieutenant, 26 June, 1826, into the Britomart 10, Capt. Fred. Chamier, on the Jamaica station; whence he returned in a few months to England. He was afterwards, from 9 March, 1838, until Sept. 1841, employed at Liverpool in the Redwing steam-vessel, Capts. Edw. Chappell and Thos. Bevis; and for his services in command of the E.I.Co.’s war-steamer Pluto at the capture of Woosung, Shanghae, and Chin-Kiang-Foo, he was advanced, 23 Dec. 1842, to his present rank. He has since been on half-pay. Agent – J. Chippendale.