CHAPTER IV

TIRED BRAIN AFFECTING MUSCLE POWER

When Professor Mosso wished to find out whether a tired brain makes any difference with a man's power to work hard with his muscles, he asked two of his friends

to use a finger machine which he had invented, and which he called an ergograph.

The machine held the hand, wrist, and arm in a firm position, but it left the middle finger free for use. To this was fastened a string which was tied to a six and a half pound weight at the other end. The finger was to raise that weight as high as it could once every two

seconds, and to continue the work as long as possible. As this went on, a pencil which was fastened to the string drew a separate dark line on a piece of paper for every pull that the finger made, and these pencil marks showed the number

of times the weight was raised and the height of each raising.

Dr. Aducco and Dr. Maggiora were the friends who lent their hands to Dr. Mosso for the fingerpulling contest. That is, each consented to have his middle finger tested. The tests were to be made under all sorts of conditions, when the brain was rested and when it was tired, when it was excited and when it was calm, when the men were well and happy and when they were ill and unhappy.

RECORD MADE BY PROFESSOR ADUCCO

The first record shows the tracing which Dr. Aducco's finger made when he himself was in a rested, healthy condition. Notice the curve. It is rather round and full and ends abruptly. Compare this with the next— Dr. Maggiora's record. Here the abrupt change is in the beginning, so that we have a hollowed-out curve and a tapering end. Such a difference is what is called. the "fatigue curve" of the two records; but each finger

had tried to do precisely the work which the other had done. Each had raised the weight as high as it could once every two seconds, and had kept doing this as long as it could. Moreover, each man was healthy and each was twenty-eight years old. They had the same kind of occupation, lived the same sort of lives, and the one was as busy every day as the other. In all these things they were alike, yet the wonderful ergograph betrayed at least one vital difference between them their fingers could not pull the

WHEN DR. MAGGIORA USED THE
ERGOGRAPH

same curve.

There were fluctuations in health, and the curve changed to correspond. There were fluctuations in excitement, in brain fatigue, in rested conditions, and the ergograph gave a correct report for every change. Indeed, it finally came to such a pass that even when the men made no confession about their recent doings, if either of them went to the ergograph, used it, and went

away, Dr. Mosso, by looking at the curve, could tell with remarkable truth the state of mind or body of the one who did the pulling.

In proof of this, turn to Dr. Maggiora again. With all the other teachers in the University he was obliged

RECORDS MADE BY DR. MAGGIORA BEFORE AND AFTER AN EXAMINATION

to examine his students in June and in October of every year. He taught hygiene, and as he had many students, as he examined them orally, and as he was anxious to discover just how much each of them knew, he exerted himself with the greatest diligence over the questions he asked. In a way it was as if he were testing the brain of each student by his own brain. This is always hard work, and by the end of the examination he was probably quite as tired as his students.

He had given the ergograph one record before the examinations began; as soon as they were over he gave it another; and the time which they required was from two o'clock in the afternoon until after five. This meant

RECORD MADE BY DR. MAGGIORA AFTER THREE DAYS OF REST

three hours and a half of hard, steady brain work, with idle hands in the meantime. Now study the record and know by the long pull and the short pull that there is close connection between brain fatigue and muscle fatigue.