Febeuaey 5, 1897.] 



SCIENCE. 



209 



and of Free-Arm Movements in Different 

 Classes of persons. By Albert L. Lewis. 

 This paper gave tlie results of nearly 

 9,000 experiments on American men and 

 women and on male negroes and Indians. 

 The relative order of these four classes in 

 reacting to sound was found to be arranged 

 from shortest to longest, Indians, American 

 men, ISTegroes and American women ; to 

 light; American men, Indians, American 

 women, Negroes ; to touch ; Indians and 

 American men the same, Negroes third, 

 American women fourth. With regard to 

 ihe mean variations of the average reac- 

 tion times, the order was : in sound ; Amer- 

 ican men, Indians, American women; in 

 light, American men, Indians, Negroes, 

 American women ; in touch ; Indians, 

 American men, American women, Ne- 

 groes. The conclusion is drawn that there 

 are characteristic variations in the reac- 

 tion time and rate of movement of classes 

 of persons ; that a close relation exists be- 

 tween reaction time and rate of movement; 

 that a number of reactions is necessary to 

 give a characteristic result in each indi- 

 vidual case. 



5. Researches in Progress in the Psychological 

 Laboratory of Columbia University. By J. 

 McKeen Cattell. 



Among the subjects in course of investi- 

 gation the following were mentioned as 

 likely to be completed soon. Mr. "W. Lay, 

 lately Fellow in Philosophy, has, for several 

 years, been studying mental imagery by 

 various methods. In addition to questions 

 such as those proposed by Mr. Galton, 

 others have been set more independent of 

 immediate introspection and extending to 

 auditory and motor imagery. Among 

 others, including musicians, 100 leading 

 artists have, in letters and interviews, de- 

 scribed their imagery. Imagery has been 

 investigated by its effects on memory, and 

 in the compositions of poets and other 



writers. Mr. Lay has, finally, given special 

 attention to his own imagery and associa- 

 tions. Mr. S. I. Franz, Fellow in Psy- 

 chology, is investigating after-images. He 

 has already published experiments on the 

 threshold for after-images, and is now 

 studying the duration and nature of the 

 after-image as dependent on the intensity, 

 duration and area of stimulation. He is 

 able to correlate the effects of these magni- 

 tudes for consciousness and to analyze phys- 

 iological and mental factors. The indi- 

 vidual differences are of interest, for, with 

 the same stimulus, the image differs greatly 

 with different persons. Mr. L. B. Mc- 

 "Whood, Fellow in Psychology, is studying 

 the motor accompaniments of the percep- 

 tion and emotional results of music. The 

 movements are a series of taps made as 

 rapidly as possible and a pressure not a 

 maximum, but kept as nearly as may be 

 constant. The subject decides on his pref- 

 erences, etc., for the tones and combinations 

 used, and these are compared with the mo- 

 tor effects. Mr. H. E. Houston, Scholar in 

 Psychology, is studjang color nomenclature 

 with special reference to children. The 

 growth in accuracy and extent of the color 

 vocabulary in schools has been determined, 

 and the attempt will be made to find and 

 set a normal nomenclature for colors and 

 other classes of sensations. Other re- 

 searches were mentioned but not described. 



6. The Psychic Development of Young Animals 

 and its Somatic Correlation with special ref- 

 erence to the Brain. By "Wesley Mills, 

 McGill University, Montreal. 

 This paper was based on researches on 

 psychic development and on the develop- 

 ment of the cerebral cortex in the same 

 groups of animals. As somatic correlation 

 other than that of the brain has been con- 

 sidered in other papers, this phase of the 

 subject was not especially treated in this 

 paper. The main conclusions are as fol- 



