In such a test, in which the subject has but a narrow space within which he must mark to avoid contact with printed lines, the pencil with which the record is made is naturally of importance. It should be fairly hard and well pointed, but not so sharp as to break on slight pressure or to catch in the paper. Each subject was provided with two long No. 3 pencils, which were carefully pointed. In the sharpener used for this purpose, the tip of the pencil lead finally came to rest against a member between the two cutters and thus indicated by pressure, to the one who was doing the sharpening, that sufficient grinding had been done, since no more wood can be removed from the pencil without crushing the point already made. The points made with this type of sharpener are uniform and satisfactory.

The form of the blank used can be easily understood from inspection of figure 18.1 This particular blank was filled in with a pen for illustration. The open space between the parallel lines is 2 mm. wide; the straight lines of which the maze is composed are each 10 mm. in length.

1This form of motor test was described and figured by Whitley, Archives of Psychology (Columbia Contributions to Philosophy and Psychology), 1911.20,p.87ff. Dr. Whitley measured the total time to complete the task, adding to the score 5 seconds for each touch error.

Each course is made up of 28 of these straight lines. The test blank was properly dated and placed face down on the table before the subject, who entered his name prior to the test. A metronome was arranged to beat half seconds, that is, 120 beats per minute. The instructions to the subject were to draw in the open space a light continuous line, without touching the printed parallel lines, to synchronize his movements with the beat of the metronome, making one straight line for each beat, and to make the movements with the muscles of fingers and hand, that is, to avoid whole-arm movement. "Avoid contact with the line; keep up with the metronome," were the points stressed before beginning the task. When the blank was in position and the pencil on the proper point for starting, the metronome was released. The experimenter counted audibly with the metronome," one, two, ready, go," counted silently 27 beats, and on the twenty-eighth beat called "stop." At that moment the pencils were immediately lifted from the paper. Between trials 3 and 4 a half-minute intermission was allowed, during which the men were encouraged to shift position. In scoring the record, one error was counted for each contact with a boundary-line, and if the subject did not finish in tempo with the metronome, an error was counted for each beat that he was found behind. The tracing required about 4 minutes. The blanks were immediately turned face down at the last "stop" signal.

Fig. 18. - Specimen record for accuracy in tracing between irregular parallel lines.

Two of the errors are marked with E. The movements were in tempo with a metronome beating half seconds, and to trace each course should require just 28 beats (14 seconds).