28 July 1891 Surgeon-Captain.
1897–1898 Served on the North West Frontier of British India.
20 May 1898 Surgeon-Major Special promotion for services in the Tirah Campaign on the North West Frontier. He was the last officer to be promoted Surgeon-Major before the grant of military titles.
1898 Married Miss Mabel Repton, and had two sons and two daughters. His eldest and third sons were killed in action in 1918.
1899–1902 Served in South Africa, where he took part in the action at Colenso and in the relief of Ladysmith, and in operations in the Orange River Colony and the Transvaal.
Malta 7 Jan 1906 Arrived from England.
Malta May 1906 Officer in charge Forrest Military Hospital.
He led a party of RAMC, (Sgt Tempest, Pte Major, Pte Brown), from Forrest Hospital to the aid of Vincenzo Sare who was taken suddenly ill while gathering mussels at Spinola Bay. Sare was found dead in shallow water. Their exertions to revive him extended for over an hour during which time they applied restoratives and used every means to promote circulation and possibly restore animation to no avail.
Malta 28 July 1906 Lieutenant Colonel RAMC.
Malta Jan 1907 Officer in charge Forrest Military Hospital.
Malta Nov 1907 Presented a paper on Simple Continued fever in Malta.
Malta Jan 1908 On duty at Forrest Military Hospital St Julians Bay.
Malta 1909 Officer in charge Forrest Military Hospital.
Malta 24 Aug 1909 Left Malta on leave in England where he arrived on 28 August. Took with him seventy sandflies which had fed on patients with sand fly fever and delivered them to Sir William Leishman in London. In experiments carried out in London the sandflies were allowed to feed on healthy volunteers who five days later developed the symptoms associated with sand-fly fever.
5 Oct 1909 Birth of a son at 28, Church Road, Richmond, Surrey.
Malta Nov 1909 Struck off the strength of the Malta Command. Posted to York.
Feb 1914 Replaced by Lt Col Charles Edward Pollock as Senior Medical Officer West Africa.
1914 Served in the Great War as Assistant Director of Medical Services.
1 Mar 1915 Colonel L/RAMC.
4 June 1917 Appointed a member of the Military Division of the Third Class, or Companion, of the Most Honourable Order of the Bath, for valuable service rendered in connection with Military Operations in the Field.
24 Jan 1918 Major-General L/RAMC.
3 June 1919 Appointed an Additional Member of the Third Class, or Companion to the Most Distinguished Order of Saint Michael and Saint George, for services rendered in connection with military operations in France and Flanders.
9 Oct 1919 Major-General John Joseph Gerrard CB CMG MB was appointed Grand Officer of the Military Order of Aviz of the Portuguese Republic.
1920–1922 Principal Medical Officer Ireland during the Sinn Fein rebellion.
27 Jan 1922 Retired.
14 Dec 1938 Died in London from an accident aged 71 years.