Thanks Suzanne very much for your help. As Sherry rightly points out, I have quite a challenge with Isaac LEWIS. It seems almost conclusive that he is the same Charles LEWIS that I have in the census and there's nothing in what you've told me that seems to discount that theory. However, your revalation that his name is ben Avraham Avinu doesn't provide the help I was hoping for in locating hi father. In fact, it seems to suggest one of three possibilities: a) he is not actually my gg grandfather because he is not Halevi (which should be provable if I can locate my g grandfather's birth certificate), b). he is my gg grandfather but at the time of his marriage he didn't know his father's hebrew name (which seems unlikely, because he would then have to have remembered/proven later that he was Halevi), or c). he is my gg grandfather and someone after him "adopted" Halevi (which seems unlikley, because as I understand it, one has to prove one's ancestry to the rabbi when one registers a birth). Just to add to the confusion, he gives his father's name on his civil birth certificate as Levy LEWIS, and despite that being a very rare name, I cannot find a birth registration or census entry for any possible Levy LEWIS. Perhaps that means he had been adopted, or didnt know his father's real name. Or perhaps it means he was trying to obscure his past for some reason. So unless I've missed any other possibilities, I probably have to hope that a) turns out to be true, otherwise I will still have a conundrum on my hands, and it seeems not much prospect of a solution. Steve