THE COLOR SENSITIVITY OF THE PERIPHERAL 



RETINA. 



BY JOHN WALLACE BAIRD, 



This paper is the result of an experimental investigation conducted 

 during the year 1903-4 in the Psychological Laboratory of Cornell Uni- 

 versity. It aims to make a contribution to our knowledge of the phe- 

 nomena of indirect vision. It will present data obtained by the writer 

 in a series of experiments upon the peripheral retina, and will attempt 

 to correlate these data with the phenomena previously established, and 

 with the theoretical principles advanced from time to time by other 

 investigators. 



An unequivocal and undisputed statement of the facts of the case 

 is, of course, a necessary prerequisite to satisfactory progress in the 

 domain of theory. So long as uncertainty prevails as to what sensa- 

 tions arise under given conditions of color stimulation, there can be no 

 definite and certainly no unanimous envisagement of the process of 

 color vision. That the investigation of the present problem has yielded 

 wholly different results in the hands of different investigators is only 

 too patent from the literature ; but in late years a distinct tendency has 

 set in toward harmony in the findings of the various experimenters 

 who have attacked the problem, and it appeared for a time that we were 

 at last upon the verge of a unanimity of agreement. The hope that this 

 goal was ultimately to be reached, at least along lines already laid down, 

 was, however, dashed by the results recently published by Hellpach. It 

 seems eminently desirable, therefore, to work over the ground covered 

 by Hellpach with a view to verifying his data and to discovering, if pos- 

 sible, the ground for their variation from those of his predecessors. 



It might appear that one is doomed to disappointment who attempts 

 to solve a problem which has already been attacked without satisfactory 

 result by so many illustrious investigators. But a perusal of the litera- 

 ture of the topic reveals the fact that although these investigators have 

 for the most part failed in their ultimate object, they still made a valu- 



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