The ephemera assemblyman blog has a mesmerising gallery of last century stage hypnotist posters that are an irresistible combination of camp send-up, schlock horror and roll-up roll-up razzmatazz.
If you’re familiar with the history of hypnosis you’ll notice more than a few passing references to George du Maurier’s 1894 novel Trilby, titled after a beautiful but tone-deaf young woman who is transformed into a breathtaking singer through through the power of hypnosis.
But Trilby is unaware of her transformation and is not a willing participant, being under the thrall of the manipulative hypnotist Svengali.
Indeed, we still used the word ‘svengali’ to refer to a manager or music mogul, although it has lost many of its more sinister associations.
The novel is notable for its anti-semitic undertones, as the hypnotist fulfils the racist stereotype of the ‘cunning Jew’, but it has also been the basis of hypnosis myths to the present day – not least the idea that it can be used to ‘enthrall’ people against their will.
I also suspect that the novel is largely responsible the remarkably extensive hypnosis fetish community who get kicks from roleplaying sexual ‘mind control’ fantasies.
Mind Hacks 
Oooh…I wonder if this poster is what spurred Milton Erickson’s infatuation with the color purple? http://www.nyseph.org/images/Ericks.%20older.jpg
Not to mention his tendency to be a control-freak.
Magic Tony, Milton Erickson was color blind, but he could see the color purple.
Now you know.