The real question is what mini would be best for Professor AJ Copperthwaite, and what kind of expeditions will he (or she...?) end up on?
Copperthwaite is depicted as a slightly stout gentleman with a big Victorian beard, little round glasses, frock-coat and fez-type hat. Obviously, that's while at ease in his parlour. In another shot he's wearing a top-hat (stovepipe hat). There should be several suitable 'Darkest Africa'-type minis that would be suitable I'd think.
I've just done a search for AJ Copperthwaite, and pretty much 3 things come up - this thread, ordering the book from Amazon... and
Dampfpanzerwagen's blog (linky), apparently he was on a Copperthwaite kick a couple of months ago... and here I was thinking I discovered an unknown masterpiece

It does mean that he probably has 1 - a copy of the book, and 2 - a working scanner, so maybe if we asked him very sweetly he'd scan the pic of Copperthwaite in the front... and then at least we'd all be able to see the great man.