A ten-word sample was read before the first reading of each test. The instructions were to read as quickly as possible and to leave no errors uncorrected. When an error was left the subject's attention was called to that fact as soon as the sheet was finished. On the signal "Ready! Go!" the sheet which the subject held face down was turned by the subject and read aloud. The words were followed on another sheet (in black print) by the experimenter and the time was taken with a stop watch to a fifth of a second. Contrary to instructions 14 subjects left a total of 24 errors uncorrected on the RCNd test, 4 was the maximum for any subject, and 4 other subjects left 1 error each on the RCNb test. As each subject made 200 reactions on each test this small number of errors was considered negligible. The work was done under good daylight illumination.