November i8, 1892.] 



SCIENCE. 



nervation effort is not essential to the muscular reaction. The so- 

 called sensorial reaction is not a determinate act, but the reaction 

 upon one of the following steps of perception. The relation be- 

 tween subject and predicate in an act of judiiment is a particular 

 case of the law of perception. The consciousness of difference 

 has no ground in the sense of time. The so-called time of choos- 

 jng shows no element of will. 



Mrs. C. L. Franklin, after explaining the difiSculties of the 

 Hering or the Young- Helmholtz theories of light sensations, pro- 

 posed the following new theory: In its earliest stage of develop- 

 ment vision consisted of nothing but a sensation of gray (using 

 the word gray to cover the whole series, black — gray — white). 

 This sensation of gray was brought about by the action upon the 

 nerve-ends of a certain chemical substance, set free in the retina 

 under the influence of light. In the development of the visual 

 sense, the molecule to be decomposed became so differentiated 

 as to lose only a part of its exciting substance at once ; these 

 chemical constituents of the exciter of the gray sensation can 

 therefore be present separately and cause the sensation of red, 

 green, and blue. A recombination of these substances produces 

 the gray sensation ; the mixing of these three colors gives a sen- 

 sation of no color at all, but only gray. The theory is that of a 

 differentiated color-molecule. 



Professor Pierre Janet gave a somewhat extensive description 

 of a disease which he designates as a new form of psychological 

 disaggregation, a mental disease consisting in the weakening of 

 the power of synthesis, which permits during each moment to at- 

 tach new psychological phenomena to the personality, which are 

 reproduced in the mind. This disease has different forms, ac- 

 cording as the incapacity for synthesis affects the sensations, 

 movements, or souvenirs. 



Professor Liegeois of Nancy showed it to be quite probable that 

 a woman, who had been condemned to twenty years of hard la- 

 bor for attempting to poison her husband, was suggestible and 

 hypnotizable to a high degree; that she had received suggestions 

 from a doctor, her lover, to poison her husband in order to be 

 able to marry the doctor; that her moral liberty was greatly 

 diminished if not abolished. Professor Liegeois commended such 

 cases to magistrates, judges, physicians, and juries, so that 

 incompetence and contradictions and excessive severity may be 

 prevented. 



Dr. Liebeault and Professor Liegeois described a case of mono- 

 maniacal suicide, which was cured by suggestion during hyp- 

 notic sleep. It was a woman who had had tendencies to suicide 

 for eleven months. 



Dr. Berillon, editor of the Revue de I'Hypnotisme, spoke on the 

 applications of hypnotic suggestion to education. From an expe- 

 rience of attempting hypnotism with some 250 children of both 

 sexes, he deduced these conclusions: In ten children from six to 

 fifteen, of different cla^^sesof society, eight could be put into pro- 

 found sleep after the first or second seance. Contrary to the 

 general opinion, the difBculties of causing profound sleep were 

 greater in proportion as the child presented neuropathic heredi- 

 tary defects. Healthy children with good antecedents were gen- 

 erally very suggestible, and consequently hypnotizable; they are 

 very sensitive to imitation. While their sleep has the appearance 

 of normal sleep, yet it is easy to obtain amnesia on awaking, 

 negative hallucinations, suggested dreams, and automatic accom- 

 plishment of suggested acts. This sensibility to suggestion and 

 liypnotism has been utilized in treating cases which concern peda- 

 gogics as much as medicine; such are those with nervous in- 

 somnia, nocturnal terrors, somnambulism, cleptomania, onanism, 

 incontinence of urine, inveterate laziness, filthiness, and moral 

 perversity. These facts have been verified by a large number of 

 authors; they belong to practical psychology. Suggestion con- 

 stitutes a process of investigation which permits us to submit to a 

 rigorous analysis the different intellectual faculties of children, 

 and thus to aid pedagogics by the experimental method. 



Mr. P. W. H. Myers, in a paper on "The Experimental Induc- 

 tion of Hallucinations," considers it a drawback to experimental 

 as compared with introspective psychology that we are liable to 

 lose in profundity what we gain in precision; new experiments 

 are required if the operations of the subconscious strata of our in- 



telligence are to be reached ; such operations tend to be manifested 

 spontaneously in forms of active and passive automatism, such 

 as automatic writing and visual or auditory hallucinations. As 

 to the extent to which these phenomena can be reproduced ex- 

 perimentally, hypnotism is at present the principal means. A 

 form of hallucination which is harmless and easily controlled is 

 " crystal vision," that is, the induction of hallucinatory images by 

 looking steadily into a crystal or other clear depth or at a polished 

 surface. In this way the crystal helps the externalization of 

 those images, sometimes by scattered reflections which suggest 

 points de repere; or by partially hypnotizing the gazer. But a 

 crystal vision may sometimes pass insensibly into the summoning 

 up of externalized images, or quasi-percepts, with no definite nidus 

 or background. Such images, or percepts, may depend upon a 

 perceptivity antecedent to sensory specialization and of wider 

 scope. 



In speaking of experiments in thought-transference, Mrs. Sidg- 

 wick considered the hypnotic state as favorable in such inquiries. 

 By thought transference is meant the communication of ideas 

 from one person whom we call the agent to another called the 

 percipient, independent of the recognized channels of sense. Mrs. 

 Sidgwick conducted her experiments in conjunction with Pro- 

 fessor Sidgwick and others. The successful percipients were 

 seven in number, and were generally hypnotized. It was possible 

 to transfer numbers, mental pictures — that is, mental pictures in 

 the agent's mind — and induced hallucinations given by verbal 

 suggestion to one hypnotic subject and transferred by him to 

 another. There were failures, but the proportion of successes 

 was sufficient to show that the result was not due to chance. One 

 percipient succeeded in experiments with numbers, when sepa- 

 rated from the agent by a closed door and at a distance of about 

 seventeen feet. Sometimes the ideas reached the percipient as 

 visual impressions received with closed eyes, sometimes as halluci- 

 nations on a card or paper, or by automatic writing, or by table 

 tilting. 



It is not known how to produce results at will ; only certain 

 persons seem capable of acting as agents or percipients, and these 

 persons succeed at one time and fail another, varying at different 

 times in the same day; the reason for this is as yet unknown. 



In the nerve-centres of flying in certain insects, Alfred Binet 

 showed that the dorsal root is motor and the ventral root is sensi- 

 tive. 



Professor Preyer of Berlin read a paper on the origin of 

 number. All concepts can arise through the senses only. No 

 concept (even the concept of number) through heredity alone, 

 without individual sense impressions, can take place. But the 

 child, like many animals, can value things and numbers without 

 knowledge of numbers; it feels the numbers, not by means of 

 touch or sight, but through hearing. The series of positive whole 

 numbers did not arise originally through addition of 1 to 1 ; such 

 a hypothesis presupposes a knowledge of a number, namely of 2, 

 and a method of adding. Numbers are acquired in a normal way 

 through hearing and comparison of tones, but later through 

 touch and sight. 



As to the effect of natural selection on the development of 

 music, Dr. Wallaschek said that primitive music is not an abstract 

 art, but, taken in connection with dance and pantomime, is bound 

 up with the necessities of primitive tribal life, that is, in war and 

 hunting, for which these dances seem to prepare, and, further, 

 that it helps the tribe to maintain its strength and skill during 

 times of peace. These dances are of a social nature, being per- 

 formed by the whole tribe with great exactness, due to the influ- 

 ence of rhythm, of which primitive music chiefly consists. This 

 tie of music enables the community to act as one body, holding 

 the community together. Tribes accustomed to play at war and 

 hunting associate more easily, act better in case of need, and so 

 are better prepared for life. The musical faculty is thus devel- 

 oped and trained for this purpose. 



Dr. Witmer presented a contribution to experimental aesthetic, 

 taking up " the sesthetical value of the mathematical proportions 

 of simple figures." No measurements of the proportions of the 

 human form, as found in nature or in art, nor in beautiful speci- 

 mens of architecture will demonstrate the aesthetic value of the 



