I can trace Joseph's PIKE ancestry back to Joseph & Katherine who lived at Chudleigh, Devon, in the mid 1700s, but if you have earlier information then I'd be happy to see it.
As for Joseph at Instow, this is the first that I've seen of his marriage record, so thank-you for bringing it to my attention! Unfortunately, there don't seem to be any birth registrations for children with Pike+Negus parents, although I haven't yet checked on spelling variations.
There is a death registration in 1946 for a Dorothea V Pike, age 67 [hence born about 1879] in the district of Bideford, Devon ... this looks likely to be Joseph's wife.
- David.