So - The Button (whereever and whomever you are) - can you remember which song and singer Hammond collected from?
I will look at my Marrowbones tonight and see and if I can find what you speak of.

By the way - thanks everyone for the response thus far on this thread - Great!

Tim Radford
(Who spent a large part of today checking which keys his source singer sang in and which keys I am going to record the same song in!)