450 



SCIENCE. 



[N. S. Vol. VII. No. 170. 



croscopical Society in 1884 and President 

 in 1887 ; Vice-President for Section A of 

 the Scientific Association in 1882 and 1883, 

 and Vice-President of Section B in 1894. 

 The subject of his vice-presidential address 

 in 1883 was ' The German Survey of the 

 Northern Heavens;' in 1894 it was 'Obscure 

 Heat as an Agent in producing Expansion 

 of Metals under Air Contact.' 



Personally Professor Rogers was one of 

 the most unassuming of men, always kindly 

 and considerate in his dealings with others, 

 yet honest and outspoken. With ap- 

 parently no conception of the meaning of 

 fatigue, he was ever ready to devote hun- 

 dreds of hours, if need be, to the solution 

 of any problem that he deemed of scientific 

 importance. His time and labor were given 

 freely, with no expectation of reward be- 

 yond that which springs from the conscious- 

 ness of success. He leaves many friends 

 and no enemies, and to the cause of pure 

 science his death is a sad loss. 



W. Le C. S. 



SIXTH ANNUAL 3IEETING OF THE AMERICAN 

 PSYCHOLOGICAL ASSOCIATION. 



The American Psychological Association 

 held its sixth annual meeting at Cornell 

 University on December 28, 29 and 30, 

 1897. 



For some years the number of papers of- 

 fered at the meetings has been so great as 

 to crowd the program to a point of serious 

 inconvenience, and as a consequence the ex- 

 periment was tried this year of holding 

 simultaneous sectional meetings for the 

 reading and discussion of technical papers, 

 a plan which was apparently successful and 

 will probably be followed in the future. 



As might be expected from the traditions 

 of the Association, experimental psychol- 

 ogy predominated in the number of papers 

 offered, but both general psychology and 

 philosophy were well represented. Two 

 formal discussions were held, one on ' Phys- 



ical and Mental Tests,' on the 28th, and one 

 on ' Invention,' on the 29th. The Presi- 

 dent of the Association, Professor J. Mark 

 Baldwin, presided at the meetings. 



The opening session was given up to ex- 

 perimental papers, the first being by Dr. J. 

 P. Hylan on ' Fluctuation of Attention.'^ 

 The speaker presented experimental results 

 and offered the theory that each object of 

 attention innervates certain nervous ele- 

 ments in the cortex, distinct to a consider- 

 able degree from those innervated by other 

 objects, and that the comparative exhaus- 

 tion of one set of elements causes another 

 set to function and the direction of the at- 

 tention to change or fluctuate in accordance 

 with this change of function. 



Dr. Charles H. Judd read a paper on 

 ' The Visual Perception of Depth,' which 

 aimed to show that there is no direct per- 

 ception of depth by means of the sensations 

 of a single retina unaided by sensations of 

 movement or by binocular factors. The ar- 

 gument was supported by a demonstration 

 of certain visual illusions. 



Professor J. McK. Cattell described ex- 

 periments showing that the time of discrim- 

 ination increases as the difference in the 

 intensity of two sensations is decreased, 

 and spoke of the application of this prin- 

 ciple as a method in psycho-physics. Pro- 

 fessor Cattell also described a method for 

 studying muscular fatigue in its relations 

 to mental conditions and exhibited a new 

 instrument for fatigue experiments in which 

 a spring dynamometer is substituted for the 

 lifted weights of Mosso. Results thus ob- 

 tained were shown which do not altogether 

 confirm those of Mosso. 



Dr. E. W. Scripture presented a brief 

 summary of recent investigation at the 

 Yale Psychological Laboratory, the publi- 

 cation of which will follow in the ' Studies ^ 

 from that institution. 



Mr. Albert H. Abbott spoke on ' Color 

 Saturation,' reporting results reached by 



