My own interest is in the Church history of Ingatestone United Reformed Church where there is a gap in our own records during the 1830s-50s and for which I have been looking for external sources of information.
A postcard sent to one of our earlier ministers states that our 19th century history had overlooked the ministry of Horrocks Cock. Thesurname sometimes appears to have the suffix letter 's' and sometimes not.
However, I was surprised to see that the biographical details provided from the history of the chapel at Tockholes (Nightingale 1886) does not mention any details for him at Ingatestone, Essex,although the village of Stanford Rivers is situated in the Epping Forest part of Essex. The dates given at Ingatestone of 1848-51 would fit approximately the period immediately after Stanford Rivers and before Clitheroe given in Nightingale's book; The postcard (Rev Surman)states he came from Stanstead in Essex.
Surman gives a reference to an obituary in the 1889 Congregational Year book. I doubt most libraries would have a copy of this but Westminister College, Cambridge (a URC training facility) has copies of year books and I hope to go and follow up the obituary reference in the next couple of months. - most give a summary of all the pastorates held.