This is probably the same Bainbridge who is mentioned by Stephens (1828-1831), I, 11, 12, etc.) He was a Fellow of the Entomological ,Society from 1833 until his death, and in 1836 was appointed Curator of the collections. Neave & Griffin (1933), 66-67, record that his wages were initially six shillings a day for three days a week and that his main task was to add red labels to distinguish the Kirby collection from the rest. A committee of Messers Hanson, Shuckard and Westwood was set up to supervise his work.
Bainbridge exhibited at the meetings of the ESL., e.g. 2 March 1840 when he showed a 'monstrous Lucanus cervus one of the mandibles of which was strangely distorted', and published one article in the Transactions 'On several species of Balboceras Kirby from New Holland in the collection of the Rev. Hope’, (39, 1842,79-83). He also published 'Some new species of Cetonidae in the collection of the Rev. F.W. Hope with observations on the genus Osmoderma’, in Ann.Mag.nat.Hist., 6, 1841, 481-82.
A copy of Dejean's Catalogue, 4th edition 1837, signed and dated by Bainbridge is in the RES library (MD 9/01, 6/18)