SCIENTIFIC PROCEEDINGS (7 I ) . their hearts are functionally tested. These people are able to flex or extend heavy dumb-bells until their arm muscles are exhausted and yet the heart muscle will show no exhaustion. That is, no delayed rise in the systolic blood-pressure is obtained. Here it is necessary to use more powerful muscles, capable of doing much greater amounts of work, in order to tire the heart. We employ in these people the 25-pound steel bar which is lifted from the floor to the

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... ulder, and above the head until the arms are fully extended. Then it is lowered quickly to the floor and raised again above the head. An adult will raise the bar between 6-7 feet, performing thus between 150 and 175 foot-pounds with each raising. In addition to the work arising from the bar movement, the raising of the trunk of the body each time from a stooping to an erect position is equivalent to a certain number of foot-pounds. The exact number is very difficult to estimate, but from some comparative experiments we are now carrying out it apparently lies between 40 and 50 per cent. of the body weight. That is, a man who weighs 150 pounds does between 60 and 75 foot-pounds of work each time that he raises his body from a stooping to an erect position. The testing of these hearts is necessarily at the present time a comparative matter, and we are unable to obtain absolute values, unless we have a bicycle ergometer at our disposal. We are much indebted to Dr. Horatio B. Williams, of the department of physiology of Columbia University, for his assistance in supervising the experiments conducted with the bicycle ergometer and for many valuable suggestions made during the course of the work outlined above. (1094)