Surgeon General John Sarsfield Comyn was the second son of Francis Comyn, of Woodstock, County Galway and Kilcorney. He entered the Army Medical Department in January 1858. He served in the Egyptian Campaign of 1882 and was specially promoted to Brigade Surgeon for his services. In 1881, he married a daughter of Major General Charles Henry Owen Royal Artillery.
22 Jan 1858 Commissioned Staff Assistant Surgeon, vice Staff Assistant Surgeon James Good who became Assistant Surgeon 43rd Foot on 3 November 1857.
8 Apr 1858 Appointed Assistant Surgeon Royal Artillery on the resignation of Assistant Surgeon Oswald Home Bell. Served in the Royal Artillery with 9th, 10th Brigades and 23rd Brigade from 1861 to 1872 (Malta and Canada).
Malta 21 July 1864 Arrived from England.
Malta June–July 1865 In medical charge of the Brigade of Artillery when cholera broke out amongst the families quartered at the plague hospital on Manoel Island.
Assistant Surgeon John Sarsfield Comyn RA recommended the removal of the families from the plague hospital to an encampment at some distance on a dry and airy ridge close to Fort Tigné. On 1 July the families of the Royal Artillery were instead transferred to Saint Salvatore Counter Guard across the Quarantine Harbour, almost directly opposite to the plague hospital.
Saint Salvatore Counter Guard was a small works overlooked by a high bastion, on which were constructed stores used as Floriana Barracks. The counter-guard was close to and on a line with the Ospizio dei Vecchi. Its shape was irregular, consisting of five ill ventilated dark casemated rooms formed in the bastion and shut in at each end. The drainage entered immediately below the works into Pieta Creek. At the time of the removal of the families from Manoel Island, there was hardly anyone from the 34 families of the Royal Artillery that did not have diarrhoea. Within a few hours of leaving the plague hospital and settling down in their new quarters, six women fell ill in the casemates, with one death.
On 2 July, another women died of cholera. On 3 July, a woman who had not been at the Plague Hospital, but has nursed the cholera patients, became infected and died within five hours. As the sick could not be removed from the counter-guard they were left in the casemates, while the healthy families were placed under tents about 137 meters away from the barracks. On 6 July, three children were attacked in the tents at Saint Salvatore with one death; on 7 July, a soldier died in the tents at St Salvatore; on 9 July, the wife of a sergeant in charge of the casemates was seized and died; on the same day, a soldier belonging to Fort Tigné, who had been on fatigue duty at the tents at St Salvatore, was attacked and died at the General Hospital. The last case in this detachment, that of a child who recovered, occurred on 11 July. Cholera had attacked seventeen and killed ten.
During its prevalence in Saint Salvatore Counter Guard and the tents Mr Comyn devoted strict attention to the disinfection of excreta, flushing and deodorisation of the latrines, and destruction of infected clothing and bedding. On the 14th July after the counter-guard had been fumigated, cleansed and whitewashed it was reoccupied by the remainder of the ill fated occupants of the plague hospital.
Malta 1866 On garrison duty.
Malta 8 Feb 1867 Left for Canada.
1 Apr 1873 Promoted from 14th Royal Artillery at Newcastle to Staff Surgeon Major at Netley.
8 June 1874 Qualified Bachelor of Medicine at a private examination held at Trinity College, University of Dublin.
1875–1880 On duty in Madras.
Mar 1875 Surgeon Major J S Comyn MB was appointed to the medical charge of the 1st Battalion 21st Fusiliers of Dublin.
Feb 1880 Moved to Purfleet from Madras.
1880–1881 On duty in Woolwich.
10 Aug 1881 Married Sophia Agnes Owen, daughter of Major General Charles Henry Owen RA.
July 1882 Ordered to embark on the Expedition to Egypt.
Oct 1882 Moved to Woolwich.
18 Nov 1882 Special promotion to Brigade Surgeon for his services in Egypt.
Dec 1882 Moved to Colchester.
15 Jan 1883 Brigade Surgeon J S Comyn retired with the honorary rank of Deputy Surgeon General after 25 years' full-pay service.
15 Mar 1883 Birth of a daughter, Sophia Honoria.
18 Jan 1887 Birth of a son, Francis Hy Ulysses.
Aug 1890 Moved to Bradford.
Mar 1902 Retired Lt Col relinquished the medical charge of troops at Bradford.
18 Aug 1904 Marriage at St Paul's Church Southsea, by the Rev W H Bircham, Lt William A Usher RNR HMS Apollo nephew of General John Usher of Ealing, to Sophie Honoria, only daughter of Surgeon General J S Comyn, of Woodstock Galway and of 21 Ashburton Road Southsea, and grand daughter of Major General Owen RA of Camberley Surrey.
- Drew R., 1968. Entry No: 5664. Medical Officers in the British Army 1660 – 1960. Volume 1: 1660 – 1898. London: Wellcome Historical Medical Library.
- RAMC/PE/3/27/Drew. Manuscript for Drew's Roll.
- Succession Book Vol 10. Returns of service of medical officers in the Regular Army.
- The Tuam Herald Saturday 8 May 1909 Tuam County Galway.