Doorman writes:

"Think of Little Walter, Muddy Waters’s harp-player, working over the saxophonist, out-doing him in a game of tag, and with that ridiculous little toy instrument with the silly name, the harmonica—Little Walter savvy enough to blow it through a mike and make noises that’d lame a sax. "

- as in, "mouth organ".

(I'm reminded of this after every practice, when the keyboardist & the guitar players are lugging all their heavy equipment to the cars... I feel ever so slightly guilty picking up my 3"x8", 1.5 lb "toolbox" containing 12 "organs"...)