Year of birth is a guesstimate. He was probably the William Jacob who was a witness to the 1752 deeds which confirmed his cousin The Revd Arthur Jacob as a tenant of Solomon Richards. The families of Jacob says of him: "......whom we conjecture to have been a solicitor, inasmuch as we find his name frequently occuring in deeds of the landed proprietors in his county. We find that in 1747, a renewal for 999 years of the lease of the Wexford property held by his father at £1 15s rent, was granted to William Jacob of Enniscorthy, Gentleman by the Corporation of Wexford, which lands are identified as being the same held by his grandfather, John Jacob of Sigginstown. This William Jacob died without issue, and probably unmarried, and being intestate the whole of his propertywent to his brother."