402 



Prof. J. S. Macdonald. 



Table I. — Briscoe. 

 V = strides per second. Q = residue or " cost of movement." 



V 



1 "333 



2 -000 



2 -400 



2-466 



2-667 



3-200 



3-267 



logV 



0-124 



301 



0-380 



0-392 



"426 



0-505 



0-514 



Q 



22 



32 



42 



44 



49 



70 



76 



log Q 



1 -342 



1 -505 



1 623 



1 -643 



1 -690 



1 -845 



1-881 



Further Additional Data (Douglas). 



To complete the range of data essential to a full consideration of the " cost 

 of movement," I have, of necessity, had to consult the data given by other 

 investigators, and have chosen as most suitable for my purpose equivalent 

 data published by Douglas and Haldane,* which are in their original form 

 measurements of the oxygen absorbed and the carbon dioxide produced by 

 Douglas when walking on the grass at Oxford at rates varied from 2 to 

 5 miles per hour. These data have been converted into calories per second, 

 following the Zuntz and Schumburg method in exact detail. The method 

 may be readily ascertained from Benedict and Cathcart's description.f This 

 done, I have converted " miles per hour " into " strides per second " in an 

 arbitrary fashion, since the stride-length of Douglas is not given. For this 

 purpose I have credited him with a length of stride of - 837 metre 

 (33 inches), thus allowing - 533 stride per sec. as the equivalent of 1 mile 

 per hour. 



In dealing with these data no subtraction whatever has been made. The 

 view is taken that the process of " walking on the grass at Oxford " is not 

 associated with any other than a negligible amount of external work per- 

 formance. The whole heat production is thus in this case treated as " cost of 

 movement," and is dealt with as if caused by phenomena completely 

 resembling those underlying the residue of heat production in Briscoe's case, 

 completely, that is to say in everything but magnitude. 



Table II. — Douglas Walking on the Grass at Oxford. 

 V = strides per second. H = heat production in calories per second. 



V 



2 -667 



2 -400 



2 -133 



1 -600 



1 -067 



logV 



0-426 



380 



0-329 



-204 



0-028 



H 



210 



164 



131 



88-5 



63 



logH 



2 -322 



2 -215 



2-118 



1 -947 



1 -799 



* 'Journ. Physiol.,' vol. 45, p. 235 et seq. (1912); also quoted in 'Phil. Trans.,' 

 B, vol. 203. 



t ' Muscular Work — A Metabolic Study, with Special Eeference to the Efficiency of 

 the Human Body as a Machine,' Carnegie Institution, Washington, 1913, p. 33. 



