text:  I had already asked respecting mesmeric sleep-waking 'Does it exist?' and to this question the cases which had fallen under my notice and which were above suspicion seemed to answer decidedly in the affirmative: but it was essential still further to enquire 'Does it exist so generally as to be pronounced a part--though a rarely developed part--of the human constitution?' In order to determine this it was requisite to observe how far individuals of different ages stations and temperaments were capable of mesmeric sleep-waking