A Question for the Historical Costumers

[gnomi]

OK, so I'm editing a novel set in Victorian England, and a question arose that neither the author nor I know the answer to. That is, how were the fastenings of men's trousers referred to (and by trousers, I mean that which we call "trousers" in modern American English?

Anyone who can answer the question or point me to an answer gets a virtual cookie.

Thanks!