William G. Holford, mining engineer, was the son of Reverend William Holford of Grahamstown. He was educated at Edgbaston College in Birmingham, England, until 1881 and then completed an apprenticeship with a firm of mechanical engineers at Leeds. After a few years in the employ of Creighton and Sons of Manchester he came to the Cape Colony in 1884. In 1886 he joined the construction department of the Cape Government Railways, but a year later moved to the Witwatersrand where he did survey and engineering work. Among others he reported on the mining possibilities of several properties on the Malmani goldfields, near Ottoshoop. In 1891 he went to Rhodesia (now Zimbabwe) to report on possible avenues of transport between Salisbury (now Harare) and Tete on the Zambesi River. Returning to the Witwatersrand he became an associate member of the (British) Institution of Civil Engineers in 1892, and worked for Godfrey and Bailey, surveyors and engineers, from 1892 to 1894. In the latter year he joined the Anglo-French Exploration Company and became consulting engineer for many companies operating in the eastern part of the South African Republic (Transvaal). During the Anglo-Boer War (1899-1902) he was on active service in the 2nd Brabants Horse before joining the Rand Rifles. He left the Anglo-French Exploration Company in 1912 to become a consulting engineer in private practice. On 12 October 1901 he married Kathleen M. Palmer, with whom he had two sons. The family resided in Johannesburg.
Holford was co-author, with E.F. Heneage*, of "Notes on the occurrence of gold in primary formations", published in the Transactions of the South African Association of Engineers in 1905. Later he contributed some articles to the South African Mining and Engineering Journal, dealing with oil occurrences on the farm Madrid (1923) and platinum and chrome mining near Rustenburg (1925). He became a member of the Geological Society of South Africa in 1903, served on its council from 1904 to his death in 1927, and was president in 1924. His presidential address dealt with mineral production in South Africa. In 1903 he also joined the South African Association for the Advancement of Science, serving on the committee for Section C in 1904. By 1899 he was a member of the Chemical and Metallurgical Society of South Africa and after the Anglo-Boer War a member of the renamed Chemical, Metallurgical and Mining Society of South Africa. He was a member (and council member) also of the South African Association of Engineers. In later years he was elected a Fellow of the Royal Colonial Institute.