Two points may be mentioned here. Improvement of _vision_ seems sometimes to result from relaxation of an involuntary ciliary spasm, which habitually over-corrects some defect of the lens. This is interesting, from the analogy thus shown in quite healthy persons to the fixed ideas, the subliminal errors and fancies characteristics of hysteria. The stratum of self whose business it is to correct the mechanical defect of the eye has in these instances done so amiss, and cannot set itself right. The corrected form of vision is as defective as the form of vision which it replaced. But if the state of trance be induced, or if it occur spontaneously, it sometimes happens that the error is suddenly righted; the patient lays aside spectacles; and since we must assume that the original defect of mechanism remains, it seems that that defect is now perfectly instead of imperfectly met. This shows a subliminal adjusting power operating during trance more intelligently than the supraliminal intelligence had been able to operate during waking life. Another point of interest lies in the effect of increased attention, as stimulated by suggestion, upon the power of hearing. Dr. Liébeault[78] records two cases which are among the most significant that I know. If such susceptibility to self-suggestion could be reached by patients generally, there might be, with no miracle at all, a removal of perhaps half the annoyance which deafness inflicts on mankind. I pass on to cases of the production by suggestion or self-suggestion of hyperæsthesia,--of a degree of sensory delicacy which overpasses the ordinary level, and the previous level of the subject himself. The rudimentary state of our study of hypnotism is somewhat strangely illustrated by the fact that most of the experiments which show hyperæsthesia most delicately have been undertaken with a view of proving something else--namely, mesmeric _rapport_, or the mesmerisation of objects, or telepathy. In these cases the proof of _rapport_, telepathy, etc., generally just falls short,--because one cannot say that the action of the ordinary senses might not have reached the point necessary for the achievement, though there is often good reason to believe that the subject was supraliminally ignorant of the way in which he was, in fact, attaining the knowledge in question. In these extreme cases, indeed, the explanation by hyperæsthesia is not always proved. There _may_ have been telepathy, although one has not the right to assume telepathy, in view of certain slighter, but still remarkable, hyperæsthetic achievements, which are common subjects of demonstration. The ready recognition of _points de repère_, on the back of a card or the like, which are hardly perceptible to ordinary eyes, is one of the most usual of these performances.