James Martin studied in the natural sciences at St John's College, University of Cambridge, and was awarded the degree Master of Arts (MA). From 1887 to 1910 he was a teacher with the title of professor at the Diocesan College ("Bishops"), an Anglican institution in Rondebosch, Cape Town, There he taught natural science, but from 1903 mainly chemistry. During these years the college provided some tuition at the teriary (post-matric) level, but the importance of its advanced teaching gradually declined until it was abolished in 1910.
James Martin was probably the author of A lecture note-book on chemistry, adapted to the matriculation syllabus of the University of the Cape of Good Hope (Cape Town, 1897), although this work is ascribed to John Martin of the Diocesan College in both the South African bibliography.... (1979) and the National Library of South Africa online catalogue. In 1899 the University of the Cape of Good Hope admitted James Martin to the MA degree on the basis of his degree from the University of Cambridge. During 1889-1890, and again from 1901 to 1912, he was an examiner for the university, setting papers at the BA and MA levels in inorganic, organic, technological and agricultural chemistry, and qualitative analysis. From 1903 to 1916 he was a member of the university council. For a brief period around 1899 he was an associate of the Chemical and Metallurgical Society of South Africa. During a wide-ranging debate around 1906 on the organisation and future of tertiary education in South Africa he argued that institutions that provided tertiary education should strive to promote unity between the two European language groups (English and Dutch), and between the various colonies.
James Martin left the Diocesan College in 1910 to take up a post as lecturer in mathematics under Professor David Williams* at Rhodes University College, Grahamstown. In 1917 (during World War I) he was acting professor of mathematics at Rhodes, while Professor Williams was on active service.