422 THEORY OF INJURY AND RECOVERY. II 



in the mixture, and that when these values are experimentally deter- 

 mined for any two mixtures they can be calculated for any other 

 mixture. When this is done we can calculate the course of the death 

 curve in that mixture. 



Having thus accounted for the death curves, we may turn our atten- 

 tion to the process of recovery. We find that, when tissue is removed 

 from a mixture of NaCl and CaCl2 and replaced in sea water, the re- 

 sistance at once rises or falls and after a time becomes stationary. 

 This rise or fall of resistance may be called recovery. 



8434 

 CaCl, In 



Fig. 3. Graph showing the increase of Ka -^ Km and the value of Kr -e- Ks 

 as the molecular per cent of CaCl2 increases. The figure shows that CaCl2 acts 

 as a catalyzer of the reaction A ^y M (which has the velocity constant Ka) and 

 also of the reaction R -^ S (which has the velocity constant Kr). The figures on 

 the ordinate at the right show the values of Kr -t- Ks; those on the ordinate at 

 the left show the increase in the value of Ka -^ Km over the value found in the 

 mixture containing 1.41 per cent CaCl2. The abscissae denote molecular per cent 

 of CaCl2 in the surface (not in the solution). 



In order to account for the facts we suppose that when we replace 

 the tissue in sea water the reactions O -^ S -^ A -^ M —^ B proceed 

 at the rates which are normal for sea water. The manner in which 

 the rate of recovery is calculated has been explained in detail in a 

 previous paper. ^ It is assumed that during the exposure to any of 

 the mixtures the following reactions occur: (1) iV — > -^ P; (2) 

 R -^ S -^ T; (3) A —^ M —^ B. By assuming values of the velocity 



t 



