There is one Jacob appears in the 1881 census - this might be a way in for you. I'm sure you must have access to this but if not I can certainly help you. I am VERY keen to learn more about Empsons in East Anglia. They are by far the largest group but few people are researching them.
I am building up database on Empsons (in England mostly) and am happy to do look-ups for anybody. I am very happy to run (or at least walk quickly) Empson errands for people outside England or without easy access to a big library.