Date of Seniority Royal Navy 24 February 1800
John Rodmell was appointed Surgeon in the Royal Navy on 24 February 1800. He was appointed to the Scipion in 1812. 
He was entered in the Navy List of Medical Officers in 1814.
John Rodmell was appointed Surgeon Superintendent on three convict ship voyages to Australia:
to NSW in 1822
to NSW in 1823.
Woodman to VDL in 1826.
He died on the voyage of the Woodman in 1826. - The Woodman, Capt. Daniel Leary, burthen 419 tons, from Sheerness, 6th December, Cape of Good Hope, 4th March with 146 male prisoners, 4 having died on the passage; and also the Surgeon Superintendent Mr. Rodmell. In consequence of the death of Mr. Rodmell, Mr. (Cornelius) Kellie of H.M. Ship Helicon, undertook the charge at the Cape. The guard consisted of Captain Wakefield, and Ensign Innes of the 30th and 2 sergeants and 7 rank and file of the 57th
 Naval Chronicle
 Sydney Gazette 24 May 1826