118 



PHYSIOLOGY 



CHAP. 



gait, the shorter it becomes, and according to the Webers in very 

 rapid walking its duration is reduced to zero, i.e. one leg is raised 

 as soon as the other touches the ground. This, however, is contra- 

 dicted by Carlet, who found a brief period in which both feet were 

 on the ground, even in the most rapid gait. The rate of swing 

 of the relatively passive limb depends on the stature or the length 

 of limb. The shorter the limb, the more rapid the swing. 



The speed of walking depends upon the length and duration 

 of the steps, i.e. the distance traversed in the time unit. Numerous 



FIG. 78. Chronophotograph of walking; shows the successive positions taken up by the joints 

 and bones of the limbs in the step. (Marey.) 



experiments of the Webers show that as an individual increases 

 the length of his steps their duration diminishes, so that when 

 walking at full speed the duration of the steps is minimal and their 

 length maximal. This can be verified from the figures given by 

 the Webers in the following table : 



This law of the inverse ratio between length and duration of 

 steps only holds, according to Marey, up to a certain point. When 



