27 June 1811 Hospital Mate General Service.
25 June 1812 Assistant Surgeon 1st/51st (2nd Yorkshire, West Riding, Light Infantry) Regiment.
18 June 1815 Served at Waterloo with 1st/51st Foot. Part of the Fourth Division (Lt Gen Sir Charles Colville), 4th Bde (Col Mitchell). 4th Bde consisted of: 3rd/14th Foot, 2nd/23rd Foot, 1st/51st Foot.
18 Jan 1827 Assistant Surgeon John Frederick Clarke MD 51st Foot was promoted Surgeon to the Forces vice Staff Surgeon Michael Sweeny who became a Physician to the Forces.
4 Sept 1828 Assistant Inspector of Hospitals. Principal Medical Officer Sierra Leone.
11 May 1830 Reduced to half-pay.
22 May 1835 Back on full-pay.
Malta Oct 1835 Principal Medical Officer. Took charge of the medical department in accordance with General Orders of 20 Oct 1835.
Malta 1836 On garrison duty.
Malta June–Oct 1837 Epidemic of cholera in Malta.
Malta June 1837 Member of the Central Committee for the supervision of cases of cholera.
Distinguished himself during the Cholera epidemic of 1837.
Malta 15 July 1838 On leave on urgent private affairs.
Malta 14 Feb 1839 Returned from leave.
9 Aug 1839 Promoted Deputy Inspector General of Hospitals, vice DIGH John Arthur, who returned to half-pay.
26 Sept 1839 Left for Van Diemen Island, (modern Tasmania), where he served as Colonial Surgeon Hobart Town until 1844.
5 Sept 1843 Promoted Inspector General of Hospitals vice IG Frederick Albert Loinsworth who died at Calcutta on 21 Aug 1842. Consequently Staff Surgeon 1st Class John Robertson was recalled from half-pay and promoted Deputy Inspector General of Hospitals vice Clarke.
1844 Inspector General of Bengal Hospital at Calcutta.
25 June 1847 Retired to half-pay. Deputy Inspector General of Hospitals Henry Franklin was promoted Inspector General of Hospitals vice Clarke.