474 PHYSIOLOGICAL, EEGULATIONS 



This general survey of the investigation indicates the outcome 

 only to the extent that words can embody it ; its numerical features 

 remain in tabular and graphical forms. How could it be otherwise 

 in animals that teem with numbers ? 



§ 176. Equilibeations 



Some points in the physiological pattern of adjustments may be 

 emphasized. The study of water relations of dog allowed the selec- 

 tion of three quantities : deficit or excess (load) in the whole body; 

 rate of gain and loss (exchange) ; and time. Reproducible types 

 of load were chosen, and occasionally the paths of exchange were 

 distinguished from one another (partitioned). Rates of net ex- 

 change increase with loads ; their correlation was termed equilibra- 

 tion (§9). Other species of animals, and finally organs, cells, 

 nuclei, and populations were found suitable for the same sort of 

 study. The general features common to the interrelations of the 

 few variables mainly treated were then formulated (§72). 



Comparable variables (loads, rates of exchange, and times) 

 were selected concerning other components of organisms. These 

 components were heat, glucose, oxygen, carbon dioxide, lactate; 

 frequency of heart beat, hydrostatic pressure of blood, excitability 

 of nerve, and some others. Regulation existed for each component 

 studied; the uniformities and quantitative contrasts among the 

 components were ascertained (§ 142). The forms of time relations 

 and equilibrations were now general (fig. 180, fig. 110). Equilibra- 

 tion diagrams also furnished a ready and exact means of classify- 

 ing the compensatory processes by which animals recover their nor- 

 mal contents (§ 72, § 142, § 178). 



Components simultaneously equilibrating in one individual 

 were interrelated. Combinations of components could be treated 

 as resultant and emergent components. Thereupon it was inferred 

 that the whole organism might be compounded of such interrela- 

 tions, each load and equilibration being compatible with many 

 others. Though methods of correlation seemed adequate to the 

 task of identifying the relations, synthesis of variables was limited 

 by ability to comprehend the multiplicity of them. Thus any one 

 equilibration, representing regulation of a single component, is one 

 member in an extensive network of mutual dependencies. These 

 were thought to constitute multiple kinetic equilibria that charac- 

 terize a physiological unit while it is maintaining its properties. 



