Russell, thank you once more with the identification of the lock and its associated key. Would you by chance have a set like that, or can you tell me where I might get one?
You are correct in your assumption that the top sits on the bottom. It used to have wooden pecks that held the top in place, but they were broken off before I purchased the sideboard. It is a beautiful piece of furniture.
Tom, that is sideboard should be American is rather interesting. It was sold to me as being “English”.
