John Andrew Tennant Mortlock

John Andrew Tennant Mortlock (30 March 1894 – 15 March 1950) was a pastoralist in South Australia, remembered as a major benefactor of the State Library of South Australia and commemorated by the "Mortlock Wing" of the library.

In 1913, on receiving news of his father's death, he left without graduating and took charge of the family properties, which included Martindale Estate and Martindale Hall, as well as cattle and sheep stations and other properties in Western Australia, South Australia and Victoria.

On 7 December 1948[3] when Mortlock was mortally ill, suffering from cancer,[4] he married Dorothy Elizabeth Beech (5 October 1906 – 10 August 1979).

His widow Dorothy Mortlock became involved with the State Library of South Australia as a member of the management committee and of the "Friends of the SLSA" and gave generously to a number of charities.

[4] In 1926 Mortlock donated £2,000 to the Waite Agricultural Research Institute, now part of the University of Adelaide.