164 INJURY, RECOVERY, AND DEATH 



In carrying out these investigations a solution of HCl 

 having the same conductivity as sea water (about 0.119 

 M HCl) was prepared. Various amounts of this were 

 added to a solution of NaCl 0.52 M (which had the same 

 conductivity as sea water). Several lots of tissue were 

 prepared with a view of maldng them as much alike as 

 possible. One lot of tissue was placed in each of the mix- 

 tures of NaCl + HCl; other lots were also placed in pure 

 NaCl and in pure HCl. 



The results are shown in Fig. 71. It will be seen that 

 in pure NaCl and in pure HCl the resistance fell rapidly, 

 indicating injury; while in a mixture in which the dis- 

 solved molecules are 99.09% NaCl and 0.91% HCl, the 

 resistance fell less rapidly, indicating that this mixture 

 was less injurious than either of the pure solutions. In 

 other words, the salt and the acid have an antagonistic 

 action. This antagonism may be expressed quantita- 

 tively (as previously explained*^) in the following man- 

 ner : The ends of the antagonism curve are connected by 

 a straight line^^ and an ordinate is erected at the point 

 on the curve which is to be measured. For example, the 

 ends of the 30 minute curve in Fig. 71 are connected by 

 the dotted line. The antagonism at the point A (repre- 

 senting a mixture in which the dissolved molecules are 

 99.09% NaCl and 0.91% HCl) is expressed as AB^BC. 



The rise in resistance at the end of 1 minute in pure 

 HCl agrees with the results previously described.^^ 



'^ See pages 122 to 129. 



"'This should in many cases be a curved line, provided the pure solu- 

 tions are not equally toxic. But in the present case the curvature would be 

 small, and at the maximum point of the curve very small indeed. This 

 line expresses the additive effect; i.e., the effect which would be produced 

 if there were no antagonism, and each component of the solution acted 

 independently. (See page 72). 



'' See page 48. 



