Irish male colonial engineer and soldier who travelled to India, New Zealand and Australia. In the process, he designed weapons and prisons, sketched Maori chiefs, had twelve children, and was a principle architect and superintendent of the Cockatoo Island colony.
sketcher, architect, civil engineer and army officer, was born in Ireland, eldest son and sixth child of Cornelius Mann and Sarah, née Fyers, was the elder brother of John Frederick Mann . After serving in the Bombay artillery, India, where he rose to the rank of captain, Mann left the service in 1836 and came to Australia. He visited New Zealand in HMSRattlesnake in 1837. The following year he married Mary Hely and settled in Sydney as an engineer in private practice. On 2 January 1844, the New South Wales Government Gazette published his name among the insolvent. He then found employment with the colonial government as a draughtsman in Captain George Barney 's Department of Royal Engineers where he designed a lightweight mortar used in the New Zealand wars. In 1854 he was appointed captain and commandant of the first Volunteer Artillery Corps raised in the colony.
From 1847, as directing engineer at Cockatoo Island, Mann was responsible for all penal and civil building design work on the island, including the free overseers’ quarters of 1850 and the second storey on the east range of the prisoners’ barracks (for which his plans survive: Dixson Library and Cockatoo Island). His sketchbooks (Mitchell Library) contain rough pencil sketches of the island and details of fittings for its buildings. In 1852 he moved into Greenwich House on the point across from Cockatoo, commuting to the island until he moved into Biloela, the superintendent’s residence on the island, in 1858. In 1859 he became superintendent at Cockatoo. His major achievement was the design and construction of Cockatoo’s Fitzroy Dock (1847-57), the first dry dock 'South of the Line’. He also designed much of the dock’s equipment. After Mann retired in 1870, he moved back to Greenwich House with his family. He and his wife had twelve children.
Mann was an indifferent sketcher yet his drawings are of interest because of their unusual subjects. These range from various engineering details to a group of sketches of Maori chiefs (drawn in 1837 in New Zealand). The latter were apparently sketched in pencil and later inked over by his brother, being inscribed, 'signed J.F.M. from the original by G.K. Mann Esq.’.