400 



Prof. J. S. Macdonald. 



Up to the present nothing but the increments have been examined, and it 

 is of interest now to observe what order can be obtained on the assumption 

 that this efficiency prevailed similarly in the total performance of external 

 work. Subtracting then the quantity EKx from the experiments in Group B, 

 and EK 2 from those in Group D, in both cases utilising the now observed 

 individual values of E and the corrected values of Ki and K 2 , the following 

 residues are obtained. 



Eesidues or Costs of Movement. 



Name. 



Group B. 



Group D. 





151 9 



152 -0 



(2) Eae 



144, -1 



144 -2 



(3) Bennett 



119 -2 



119 "6 





9L-5 



91 7 



Although the slightly greater rate of movement (603/600) in Group D 

 might have been expected to produce somewhat larger consequences, to 

 which Bennett should have proved an exception, yet the figures are very 

 satisfactory evidence of the comparability of the two groups of experiments. 

 In view of this evidence these data are accepted as entities separable from 

 the total heat production, and as representing the cost of the underlying 

 movement. Before dealing with them more precisely certain additional data 

 are introduced. 



Additional Data (Briscoe). 



Doubtless some of the accuracy of the experiments just quoted is to be 

 assigned to the monotonous repetitions of similar experiments, every 

 experiment being a " drill " in handling the very complicated apparatus 

 required, in precisely the most convenient way. The series of experiments 

 now quoted from were of a different type, since large variations in heat 

 production were measured in successive experiments. No doubt they suffer 

 to some slight degree from that fact. Then again they were not all of 

 precisely the same duration, some longer and some shorter than those of the 

 " efficiency groups " ; and in addition the calibration of the work done on the 

 cycle was not so satisfactory, nor had it the same direct relation to the actual 

 experimental rates of movement, since in several experiments the subject 

 initiated and maintained his own rate. Once that is said, however, in other 

 points they were similar. The rate of cycling was maintained the same, 

 however much it was varied in different experiments, throughout the whole 

 time of each single experiment. The sets of observations were made at the. 

 end of each five-minute period, and none are reckoned in the data that were 



