Role of Salts in Preservation of Life 183 



of the solution. It was ascertained from day to day how many 

 fish survived. 



When the fish were put into pure solutions of KCl of the 

 concentration in which this salt is contained in the sea-water 

 (2.2 c.c. m/2 KCl in 100 c.c. of the solution) they died mostly 

 in less than two days. This is not due to the low concentration 

 of the KCl solution, which is only 1/50 of that of the sea-water, 

 since the fish can live indefinitely in a pure NaCl solution of the 

 same concentration as that in which the KCl exists in the sea- 

 water. 



If we add to the toxic quantities of KCl increasing quantities 

 of NaCl, we find that as soon as the solution contains 17 or more 

 molecules of NaCl to one molecule of KCl, the toxic action of 

 KCl is considerably diminished, if not completely comiteracted. 

 The following table may serve as an example : 



TABLE III 



More accurate determinations showed that already a 3/16 m 

 NaCl solution renders the solution of 2 . 2 c.c. m/2 KCl in 100 c.c. 

 of the solution harmless. 



It was next determined whether different concentrations of 

 KCl required different concentrations of NaCl. It was found 

 that the coefficient of antagonization KCl /NaCl has an approxi- 

 mately constant value, namely, about 1/17, as the following 

 table shows. 



