[1] He was the only son of John Dunkin by his wife Anne, daughter of William Chapman, civil engineer, was born at Islington, London, on 9 August 1812.
In the belief that he was the original editor, he printed (octavo, Noviomago, 1856) twenty-five copies of the works of Radulphus, abbot of Coggeshall, to which he appended an English translation.
An imperfect copy of this unlucky undertaking, with some severe remarks by Sir Frederic Madden, is in the British Museum.
[2] While travelling in the severe winter of 1878–9, he was seized with bronchitis at Newbury, Berkshire, but managed to get up to London to the house of an old nurse at 110 Stamford Street, Blackfriars Road.
On failure of such conditions the collections are to be presented to the trustees of the British Museum; and that the family monuments at Dartford and Bromley may be maintained and renewed when necessary, he left to the lord mayor, the vicars of Dartford and Bromley, and the principal librarian of the British Museum freehold estates at Stone, Erith, and Bromley; ten guineas annually to be spent in a visitation dinner to examine the tombs and memorials ('Printing Times and Lithographer, 15 April 1879, page 89).