 He bought and restored Farleigh House at Farleigh Hungerford in Somerset and lived there for most of the second half of his life.Cairns was commissioned an officer in The Rifle Brigade, and served in the 3rd battalion.After retiring, he was on 9 February 1898 appointed a major of the 5th (Militia) battalion, previously the Queen's Own Royal Tower Hamlets Light Infantry (2nd Tower Hamlets Militia), based in Bethnal Green in the East End of London.