Method of Investigation. 11 



experiment and very little, if any, discomfort was experienced from having 

 it about the chest, even during the hours of sleep. 



Respiration rate. In addition to the work of circulation, the work of respi- 

 ration forms a considerable portion of the total amount of internal muscular 

 work and consequently any accurate data regarding the rate of respiration 

 are of importance in all measurements involving energy transformation. 

 Various attempts have been made previously in this laboratory to secure the 

 rate of respiration of subjects during experiments. By the use of a stop watch 

 the attempt has been made to count the respirations by looking through either 

 the glass window in the front of the chamber or the glass doors of the food 

 compartment. But little success attended these attempts, for the subject moved 

 so frequently that it was impossible to count the risp and fall of the chest for 

 any great length of time. Furthermore, the subject very soon became aware 

 of the fact that the respiration rate was being counted, and the difficulties of 

 counting the rate of respiration when the subject knows that the count is being 

 made are only too well understood by physicians. The pneumograph is 

 ideally adapted for giving the desired data. Indeed, it was extremely fortunate 

 that with the same piece of apparatus two such valuable factors could be 

 measured. When the curve of the respiration was drawn upon smoked paper, 

 there was obviously a superimposed curve of a much smaller amplitude showing 

 the pulse. Singularly enough, it was found that during the waking period, 

 when the subject was more or less actively moving about, more difficulty was 

 experienced in obtaining the respiration rate than the pulse rate; for while 

 the slight vibration of the pointer for each pulse beat could, as a rule, be 

 detected by the observer, the grosser vibrations due to the rise and fall of the 

 chest were frequently masked by fluctuations due to body movements. This 

 was particularly true during the period when meals were eaten. On the other 

 hand, during the night and at times when the pulse rate became very feeble 

 and almost impossible to recognize, it was practically always possible to obtain 

 the respiration rate. 



Strength tests. The importance of securing data regarding the effect of 

 inanition on strength has been recognized heretofore. The observations made 

 by the subject of the experiments of Johansson, Landergren, Sonden, and 

 Tigerstedt, 34 in which the subject noted the length of time he could suspend 

 himself on the arm, were of much value. Unfortunately, with the subject of 

 the prolonged fasts here reported, tests of strength were not included, as the 

 multiplicity of other observations made it difficult to include these in the 

 daily routine. In the later group of experiments, made on different subjects, a 

 series of strength tests was made with the Tiemann hand dynamometer before, 

 during, and after the close of the fast. Inasmuch as the element of fatigue is 



S4 Skan. Archiv f. Physiol. (1897), 7, p. 31. 



