0.030 sec. and 0.050 sec;
that for distinguishing one color from another was similarly:
0.100 and 0.110;
that for distinguishing a certain color from ten other colors:
0.105 and 0.117;
that for distinguishing the letter A in ordinary print from the letter Z:
0.142 and 0.137;
that for distinguishing a given letter from all the rest of the alphabet (not reacting until that letter appeared)
0.119 and 0.116;