An instance may be quoted in detail which illustrates at once the apparent attachment of the hallucination to an external object, and its successful competition with the impressions of waking life. A lady of my acquaintance, Sister L., was put into the hypnotic state by Mr. G. A. Smith in the spring of 1892. Whilst she was entranced, Mr. Smith, at my request, handed to her several blank cards, and told her that one of them (which had been privately marked on the back) bore a portrait of himself, and that she was to look at it ten minutes after waking. A few minutes later, when engaged in conversation and apparently completely awake, Sister L. picked out the card in question from the little heap of similar cards and showed it to me, remarking that it was an excellent likeness. Some half-hour later, when Sister L. was about to take her departure, I handed her the card and said that Mr. Smith would be glad if she would accept the photograph. She looked at the card, expressed her thanks for the gift, and placed it in her pocket. When I met her a few days later I learnt that on her arrival at home she had searched in her pocket for the photograph, and had been much surprised to find there only a blank card. In this instance there can be little doubt that a complete sensory hallucination was induced, and that it persisted, or was capable of being revived, for some 30 minutes or more after the original impression had been established. This last example, it will be seen, belongs to the important class of post-hypnotic hallucinations--_i.e._, hallucinations enjoined on the subject in the hypnotic state, but realised only after waking. Special interest attaches to hallucinations of this kind, because the subject is in a condition which, if not fully normal, at least approaches in some cases very nearly to the normal, and is thus able to observe and describe his own sensations with care.[94]