Whispering imp poster overdose

Here's a gallery of dozens of old magician posters all featuring imps whispering into the ear of the magician.

This image of the magician getting the "secrets" from these underworld demi-devils apparently started with Harry Kellar (on his 1894 poster). Leon Hermann (nephew of Alexander) who overlapped the career of Kellar seems to be the first who copied the whispering imps. Not only did the Great Hermann include them, he used more imps! Several of the imitators have been satisfied with a single informant but the standard seems to be two - one per shoulder."

Link (thanks, Digitaler Lumpensammler!)