In planning for this memory test, it could not be known how little or how much practice the men might have had in such procedures, or whether any of them were familiar with the device of fitting words together into a story for purposes of recall. This latter is a more or less common parlor game. It was therefore thought best to give a list of words which was long enough to be far above the memory span of the ordinary individual and, indeed, so long as to make the story method of recall difficult to use. Thus it was not practicable to have the words recorded in reference to the position given them in the list or to treat the results in some of the more elaborate ways which have been used in memory experiments.1 Eight series or lists, each containing 25 one-syllable English words, each word composed of four letters, were prepared and used. For the most part the individual lists were distinctive. Occasionally one specific word was embodied in two lists, but these were not used in consecutive experimental sessions. Many of the words in these lists were the same as those selected and used by Dodge and Benedict in the memory experiments of their alcohol investigation and were later employed by one of us.2 Since there were 10 sessions with Squad A, 2 of these 8 lists were given a second time, that is, list No. 1 was given on September 29 and January 26, list No. 2 on October 13 and February 2. With Squad B there were 8 experimental sessions, with no repetitions.

The words were read at the rate of 1 per second, in tempo with the metronome beating audibly to all. They were pronounced by the experimenter as distinctly as possible and without stress or grouping. The subjects were instructed to listen intently for immediate recall, to watch the lips of the one who was pronouncing the list, and to avoid whispered repetitions of the words. Immediately at the end of the pronouncing the subjects were to write on the back of the accuracy tracing blank as many of the words as could be recalled in 11/2 minutes. In any extra time which a man might have at his disposal he was to give attention to the legibility of his writing. The subjects were told that with words pronounced alike and spelled differently either spelling was acceptable, provided the word written was of four letters. No instruction was given concerning the order in which the words were to be recorded and nothing was said about the matter of insertions, that is, words written by the subjects which were not included in the lists. This latter point was considered in planning the experiment, but it was thought that if the men knew they would be penalized for each insertion they made it would tend in some cases to inhibit their best performance. Since they were given definitely to understand that they were to write only the words that they remembered, from the list which was pronounced, any other words written would be due to faulty recall or to the aim on the part of the subject to add a few extra words in the hope that he might chance upon some in the list. No instance of the latter sort is clearly demonstrated in the records. Occasionally, a subject having remembered the general sound of a word, put in two or three words consecutively which had that general sound complex, in the hope that one of these might be the exact word needed. Such special cases were given careful consideration. A word which sounded very nearly like one pronounced was given full credit. The subject may be credited one point for each word correctly recalled, and a statement of the number of errors given,1 or his errors may be subtracted from the other score by deducting one point for each one.

1 Whipple, Manual of Mental and Physical Tests, part 11, Baltimore, 1915, p. 166. 2 Dodge and Benedict, Carnegie Inst. Wash. Pub. No. 232, 1915, p. 126: Miles, Carnegie Inst. Waah. Pub. No. 266. 1918, p. 67.

Fig. 19. - A block of 100 digits arranged in 10 columns of 10 each, as in the material for addition work.

The type was 12-point and the figures are here reproduced full size. A page contained 8 such blocks of columns.

Fig. 20. - One block of the addition material showing the sums properly entered for the vertical and horizontal columns.

The same material is used for a cancellation test in which the subject marks each pair of digits which when added equal 11, as described on page 145. One error of omission is found near the center of this block.