18 



K. S. LASHLEY 



TABLE 5 



Time of reaction to one light alone. The time is that required by the chicks 

 to go from the door of the starting box to the food dish, a distance of three feet. 



At the end of these tests the lights were equated in energy, 

 the chicks were retrained for a few days to increase the accuracy 

 of their reactions and then tested with the lights under accurate 

 control. The energies of the lights were varied widely in both 

 directions from the brightness equation point and were likewise 

 varied in absolute intensity at different brightness ratios. The 

 results of the tests with the three chicks are given in table 6. 

 At the end of the experiments the chicks were offered two white 



TABLE 6 



