UNIFOEMITIES AND COMPAEISONS AMONG COMPONENTS 



379 



varieties may be distinguished. The velocity quotient may relate 

 rates to total loads (incremental k), or limit itself to any speci- 

 fied range of loads (limited k). Its rates may represent the 

 total, the net, or the partial exchange ; partial exchanges being as 

 numerous as the measurable paths for the exchanges. Diverse 

 time intervals are concerned wherever stationary states are not 

 studied. Of course the varieties and sizes of the living units com- 

 pared by the quotient are as large as taxonomy. As in all the rela- 

 tions so far discussed, therefore, there is nothing universal about 



-I +1 +2 +3 



Load'Arbitrory Units 

 Fig. 181. Velocity quotient (l/hour) of net exchanges in relation to load. Man. 

 The loads are in diverse units, the abscissae being scale divisions upon the graphs from 

 which these data are derived. Water, first 1.0 hour of recovery, figure 61. Heat, first 

 0.5 hour of recovery, figure 144. Oxygen, first 0.005 hour of recovery, figure 172. Carbon 

 dioxide, steady state, figure 171. Lactic acid in blood, first 0.5 hour of recovery, figure 

 174. Heart frequency, first 0.005 hour of recovery, figure 175. Skin healing, 96-hour 

 periods of recovery, figure 179. 



velocity quotients ; they are means of comparison among particular 

 distinguishable functions. 



Total velocity quotients, where known, vary with load, usually 

 approaching infinity at small loads and approaching stable values 

 at large loads. Even net velocity quotients are for many compo- 

 nents not constant at diverse loads ; hence some of the comparisons 

 made are arbitrary in so far as the loads present are unequal or 



