In 1866 he joined the survey department as a
chainman, was soon appointed cadet and thereafter rose up through the ranks. Engaged by
George Goyder as a second-class surveyor in 1868, he joined Goyder's expedition to the Northern Territory to survey
Darwin and the surrounding country, After successful completion of this section, he pushed on and oversaw construction of the line to
Roper River and
Daly. With surveying completed, Knuckey was appointed overseer of Section A (Charlotte Waters) of the construction party. After the line had been completed on 22 August 1872 and the first messages had been exchanged, Knuckey accompanied Todd on the return journey from
Central Mount Stuart to Adelaide, where they were given an enthusiastic reception. Back in South Australia, Knuckey was selected by Sir Charles Todd as overseer in the erection of the telegraph line from
Port Augusta, South Australia to
Eucla in
Western Australia – a distance of – in 1876. From 1880 until his retirement in 1889, Knuckey was inspector of postal and telegraph services. ==Later life==