Born in London and educated at first privately, but afterwards at King's College and at London University. Failing to find a post in the natural sciences he spent four years in an engineer's office before becoming a clerk in the South Kensington Museum. At the age of twenty three, having already spent a considerable amount of time working on the natural history of Ireland, he was appointed Assistant Naturalist at the Museun of Science and Art, Dublin. Carpenter spent the next sixteen years in this position working closely with Dr Scharff, the Curator, in building up the collections and developing the displays.
In 1903 Carpenter was elected to membership of the Royal Irish Academy, and this was quickly followed by appointment to the Council, and subsequently to the Secretaryship. In 1904 he was appointed Professor of Zoology in the Royal College of Science, Dublin, and in 1911 he accepted the position of Secretary to the Royal Zoological Society, which he held until June 1918. In 1923 he was appointed Keeper of the University Museum at Manchester which he took charge of at a time when it was being reorganised and enlarged. A great deal of his work was in connection with the fitting up and re-arrangement although he did continue his entomological activities, working chiefly on Collembola. Carpenter was always deeply religious and after four years residence in Manchester he became ordained taking up the duties of an honorary curacy. After leaving the city he became a curate at Broxbourne, Herts. before retiring in 1937.
Early in 1899 he became a member of the newly formed Dublin Naturalists' Field Club, and Secretary two years later. In 1892 he started the well known journal the Irish Naturalist, of which he remained joint editor until his retirement from Dublin in 1922, and in which he contributed thirteen articles on Coleoptera between 1892 and 1917. .
Carpenter's special concern from an early date was entomology, and also to spiders. The latter interest led to his well known List of the Spiders of Ireland, which was published in 1898, and the former to various publications including his books: Insects, their Structure and Life, 1899, largely rewritten 1924; Life History of Insects, 1913; Insect Transformations 1921; and The Biology of Insects, 1928. All these volumes include many references to Coleoptera but on beetles alone Carpenter wrote little. Apart from the papers noticed above the first volume of his Irish Naturalist contains pieces on ‘Coleoptera at Holywood, Co. Down’, on ‘Rhagium bifasciatum in Co. Cork’ and on ‘Paederus riparius in Ireland’. A note on ‘Otiorrhynchus auropunctatus with remarks on the distribution of Irish animals’, ibid., 4, 1895, enabled him to raise a favourite subject: the relationship between the Irish and Southern European faunas.
Johnson & Halbert (1902) record their thanks to him as one of the many collectors of Irish Coleoptera who assisted them. Gilbert (1977) lists seven obituaries of which the most complete is that in the Irish Naturalists' Journal, 7, 1939, 138-141 (by C.B.M., includes portrait). Pederson (2002) notes correspondence, some concerning Darwin, in the RESL. (MD 1/O2, 11/09)