Charles Abercrombie Smith, civil servant and politician, studied at the University of Glasgow from 1848. In 1853 he was awarded the degree Master of Arts (MA) in mathematics and physics, with distinction. As an assistant to Lord Kelvin he conducted some experiments on heat and thermo-electricity and in 1854 was awarded a bursary to continue his studies at Peterhouse, University of Cambridge. In 1858, despite health problems, he was second wrangler (that is, second among that year's students for the BA degree with first class honours in mathematics). The next year he was elected a Fellow of Peterhouse. After a serious illness he undertook a voyage to the East and in 1860 settled in the Cape Colony.
In 1863 Smith was the top candidate in the examination for the Certificate in the theory of trigonometrical surveying, set by the Board of Public Examiners. That same year he was admitted as a land surveyor. He worked as a surveyor in the Eastern Cape until 1872, living near the Kat River. After British Kaffraria had been annexed to the Cape Colony in 1866 he represented King William's Town in the Legislative Assembley until 1875. During these years he none the less found time to continue his studies in mathematics and published two papers in the (British) Quarterly Journal of Mathematics: "On certain geometrical properties of the caustic of reflection and its evolute, etc." (1866), and "To find the foci and axes of a conic in trilinear coordinates" (1873). From 1872 to 1875 he served in J.C. Molteno's cabinet as commissioner (minister) of crown lands and public works. In the latter year he accepted the post of auditor-general of the colony and served in this position to his retirement in 1903. In his official capacity he wrote various reports relating to public finance and served on many commissions, among others as chairman of the Public Service Examination Commission from 1887 to 1910.
From 1868 to 1873 Smith was a member of the Board of Public Examiners, serving as one of the examiners in science. When the University of the Cape of Good Hope (the first university in southern Africa, but an examining university only) was founded in 1873 he was appointed a member of its first council, serving the university in this capacity until 1916. During 1877-1879 and 1905-1911 he was its vice-chancellor. His contributions as a member of council lay mainly in the advancement of the natural sciences. From 1874 to 1893 he furthermore served the university as an examiner in several branches of mathematics and physics at the BA, BA Honours and MA levels. He was also a member of the council of the Diocesan College, Cape Town, and of the Synod of the Anglican Church.
Smith played a leading role in the development of the meteorological services of the Cape Colony. Following the retirement of Thomas Maclear* in 1873 the Meteorological Commission of the Cape of Good Hope ceased to function for a few months. However, a new Commission was appointed in February 1874, with Smith as its chairman and E.J. Stone*, Professor R. Noble*, W.L. Blore*, G. Maclear* and I.D. Den as members. Smith served as chairman for an unprecedented 37 years, until the weather services of the four South African territories were amalgamated in 1911, following the formation of the Union of South Africa in 1910. During these years the annual reports of the Commission summarised the meteorological observations of a growing number of volunteer observers throughout the colony.
Smith became a member of the South African Philosophical Society in 1877, the year of its formation, and served on its council as treasurer from 1881 to 1897. When the society became the Royal Society of South Africa in 1908 he was elected as one of its Fellows.
Smith described his recreational acitivies as "rambles to the habitats of the magnificent Cape flora". Late in life (1897) he married Christina C. Horne, but they had no children. He was knighted in 1903 for his services to the colony. In 1916 he read a paper on "The entrenchment of industry" at the annual congress of the South African Association for the Advancement of Science held in Natal. A short version of the paper was published in the Association's Report for that year (pp. 342-351) and a more extensive version as a pamphlet (Durban, 1916, 32p). In 1917 the University of the Cape of Good Hope awarded him an honorary Doctor of Laws (LLD) degree.