The Mad Hercules is not one of the best of Euripides' tragedies; but it has a particular interest for us, because it is the only one extant in which madness is personified, and introduced on the stage. This had been already done by æschylus, in his version of the story of the Bacchæ, and was adopted by Euripides amongst the terrifying effects borrowed from the elder dramatist for this play.