10 INFLUENCE OF INANITION ON METABOLISM. 



a number of cases where the rectal thermometer was not worn, his temperature 

 was taken, usually in the mouth, by means of a clinical thermometer. 



Pulse rate. As a measure or an index of the degree of internal muscular 

 activity, the pulse and respiration rates are of great value, and consequently 

 in any series of observations which include total heat production it is desirable 

 to have a continuous record, if possible, of the pulse rate and the respiration 

 rate. In the longer fasting experiments here reported, the subjects made 

 observations of their own pulse rate, sometimes as frequently as every half hour. 

 Each subject was instructed to count the radial pulse for upwards of 2 minutes, 

 noting the count during one minute and using the second minute as a check on 

 the first count. Obviously this gave no pulse records during sleep, and this 

 omission seemed so serious that an apparatus for indicating the pulse rate 

 during the whole day was secured. 



Through the kindness of Prof. W. T. Porter a Fitz pneumograph 83 was 

 obtained. This pneumograph was adjusted around the chest of the subject 

 and a stout-walled transmission tube used to connect the pneumograph with a 

 glass tube in the inner door of the opening through which food is passed into 

 the chamber. A flexible rubber tubing connected the tube in the inner door 

 with one in the outer door of this compartment, and finally a rubber tube 

 connected the tube in the outer door with a tambour. In spite of this long 

 transmission, a distance of some 3 or 4 meters, the form of tambour used gave 

 excellent results. Prof. W. B. Cannon, of the Harvard Medical School, kindly 

 came to Middletown and assisted in adapting this apparatus to the conditions 

 of experimentation. It was ascertained that when the pneumograph was 

 adjusted carefully over the apex beat of the heart the pulse rate could be very 

 accurately noted. In the earlier tests a curve was traced on smoked paper. 

 It was found later that the curve was unnecessary, since the vibrations of the 

 pointer of the tambour were so marked that the observer could count the 

 respirations without difficulty. This apparatus served its purpose admirably 

 and has resulted in our obtaining many observations of pulse rate during sleep 

 that would have been otherwise unobtainable. During certain of the fasting 

 days, and especially during certain periods of the experimental day, the strength 

 of the pulse seemed to fall off to such an extent that the minor vibrations of the 

 pointer, due to the transmission of the pulse waves, were so small as to be 

 recognized with difficulty. Furthermore, special precautions were necessary to 

 make sure that the pneumograph remained in approximately the position in 

 which it was originally adjusted. For this purpose, two or three straps of 

 canvas were placed over the shoulders to keep the pneumograph from slipping 

 down. Each subject wore the pneumograph continuously throughout the whole 



"Journ. Experimental Medicine (1896), 1. 



