He was awarded an MA degree in 1891 and emigrated to South Africa in the same year, taking up the position of vice-principal at the
Grahamstown Public School . He soon went on to become government lecturer in physics and chemistry at
St. Andrew's College in 1894. Here he founded the chemical laboratory, financed by
Barney Barnato and other sponsors. On the establishing of
Rhodes University College in 1904, Cory took up the post of Professor of Chemistry, a position he held until 1925 when he retired. After his arrival in
Grahamstown, Cory found a new interest in the history of the
Eastern Province, perhaps sparked by his home in Grahamstown having formerly been the
Drostdy, the residence of the
Landdrost or magistrate. He wasted little time in developing an intellectual circle of friends – "''Some time in 1892 or thereabouts, some of us—Meredith, Rev G W Cross,
Adv. Lardner-Burke, Webb of St. Andrew's, all now dead—and myself started a Society called the "Athenaeum"''. Cory started tracking down and questioning old
Bantu chiefs and any survivors of the
1820 Settlers. During his spare time he travelled on foot and covered large areas of the Eastern Cape, amassing an enormous amount of historical data. The magistrate's office in Grahamstown had preserved a large number of letters, bound in volumes, and pertaining to public matters – material giving useful insight into life in the 1800s. The perusal, copying and summarising of these records was tackled by Cory over a number of years. At that time
Leander Starr Jameson was prime minister of the
Cape Colony and with a bequest made by
Alfred Beit, arranged to assist Cory in his investigations, provided that some publication would result. Thus the first volume of
The Rise of South Africa appeared in 1910. The success of this volume was such that the Rhodes Trustees sponsored further work and accordingly volumes 2 and 3 were published in 1913 and 1919, volume 4 in 1926 and volume 5 in 1930. Cambridge honoured Cory with a
Doctor of Letters in 1921, and the following year he received a knighthood. Volume 6 of his work appeared posthumously in the
Archives Year Book for 1939. Some time in 1915 Cory wrote and published, in a small print run, a paper entitled "A short history of slavery at the Cape.” == Personal life ==