Hi

I am looking for a marriage of a John Williams to a Rebecca Knight, possibly in Yealmpton/Plymouth, Devon. (John Williams' parents I believe were Garland Williams and Elizabeth.) The couple lived in St Ives, Cornwall, and their first known child Richard was born in 1819 in St Ives. The last child of this couple was Nancy, who was born in 1843. Nancy's baptism was to John Williams and Rebecca (nee Knight).
I cannot find a marriage for this couple anywhere in Cornwall, so am hoping they married in Rebecca's home town instead. In 1841 she was listed as being born in Yealmpton, Devon; the 1861 census says she was born in Plymouth, Devon. Rebecca was born c. 1797.
Any help on this long-time brick wall would be greatly appreciated
