electro-plating was commonly used on jewellery and especially cutlery (EPNS = eletro plated nickel silver) but only became possible with advent of dynamos + accumulators thus likely he moved into this post 1877.

Running to Island with a new 'wife' post a family breakup might well be the reason - no backround to follow him.

However there was another Cox family on the Island who produced some in positions of note.