James Cameron studied some mathematics and chemistry in Perth, Scotland, but in 1819 was apprenticed as a carpenter. In 1824 he entered the service of the London Missionary Society, assisting with the preparation of cotton machinery for Madagascar. He left for the island in May 1826, where he taught carpentry, chemistry and brick making, built canals, a reservoir and other public works, and set up the first printing press.
After the expulsion of missionaries from Madagascar in 1835 Cameron settled in Cape Town as a builder. He may have been the first in South Africa to experiment, in 1848, with the calotype process (an early wet plate photographic process using silver iodide, invented by W.H.F. Talbot) for outdoor photography, and by 1850 he was a recognized photographer in Cape Town. In 1854 he introduced collodion photography to the Cape. He also did some analytical chemistry, for in 1852 he reported on his analysis of a coal sample to the mayor of Cape Town, H.C. Jarvis. The report was published in the South African Commercial Advertiser. In 1856 he became city engineer of Cape Town. He also compiled that portion of the catalogue of books presented by Sir George Grey to the South African Public Library that dealt with the philology of Madagascar. It is clear from these varied activities that he was a person of sharp intellect and many accomplishments.
Cameron visited Madagascar in 1853, and in 1863 returned to the island for good to supervise the building of churches. He was a competent surveyor and had a particular interest in astronomy. From Antananarivo he reported on meteorological observations made there (atmospheric pressure, humidity, rainfall, and cloud cover) to the Meteorological Commission of the Cape of Good Hope. His reports were included in the Commission's reports for 1861-1865 (pp. 30-31, 54), and 1866-1867 (pp. 15-16). Shortly before his death he published his Recollections of mission life in Madagascar during the early days of the LMS (Mission Printer, 1874).
Cameron should not be confused with two other persons of the same name. His only surviving son, Reverend James Cameron (1831-1906), was professor of Classics at the South African College (from 1860) and the first registrar of the University of the Cape of Good Hope (1873-1895). Another Reverend James Cameron (1805-1875), a Wesleyan Church minister in Cape Town, published a number of sermons between 1854 and 1867.