Christopher Toombs, son of John H. Toombs and his wife Christina, resided on the East Rand from shortly after the Anglo-Boer War (1899-1902) until at least 1934. He was a member of the Chemical, Metallurgical and Mining Society of South Africa and served on its council during (at least) 1913-1914. He contributed two short papers to the society's Journal. The first dealt with "The screen assay on the Meyer and Charlton Gold Mine under the 'new metallurgy' " (1906/7, Vol. 7, pp. 277-279); the second, as co-author with James Gray*, was on "The determination of gold in the presence of iridium and allied metals in materials such as black sand" (1913/4, Vol. 14, pp. 292-294).
In 1912 Toombs became a foundation member of the South African Association of Analytical Chemists, serving on its council from 1915 to 1922. He contributed a short paper to its Journal in 1919 (Vol. 2(1), p. 3), dealing with nitrous fumes in mine air. The association became the South African Chemical Institute in 1921, of which he was still a member in 1934. Meanwhile in 1919 he was elected the first president of the South African Association of Assayers (from 1964 the South African Institute of Assayers and Analysts).
Toombs was married to Sarah A.C. White, with whom he had four children.