Charles's mother was Cecil's wife Elizabeth (d. 1883), daughter of Colonel Henry Howe Knight-Erskine of Pittodrie.
His younger brother, Kenneth, an artillery officer, died in early manhood of phthisis in Nova Scotia.
Called to the bar at Lincoln's Inn in 1863, he did not practise, but continued his study of law, though the work was hampered by ill-health, necessitating much residence abroad.
From 1872 to 1896 he was law lecturer at his college and at some point was appointed a member of the Syndicate of Modern Languages in the university, being a good linguist.
One volume of this work appeared in 1904 and another in 1909, after his death, covering, altogether, about one-fourth of the book, published by Cambridge University Press.