I don't doubt the wheels are not original, what are they? 27", but look at the reach at the rear brake bridge. If the reach is that much with 27" think how far it would be with 26x1 3/8" wheels. Too much, at least looking at it from here. Would they have 27" wheels originally, but 32 & 40 like you say?
I think if we can figure the original wheels size, it may tell us how the bike was purposed, as a "clubman" or a utility bike.