W. J. V. OSTERHOUT 



425 



+ 10 is shown for all the solutions^" in Fig. 4, which shows the agree- 

 ment between observation and calculation in respect to the final 

 level reached by the recovery curve, but not in respect to speed of 

 recovery, which depends more on the value of 5 than on that of 0. 

 The rate of recovery seems to be about the same in the mixtures as 

 in the pure salts. In general it is found that the rise or fall is nine- 

 tenths completed in about an hour. 



Fig. 5 shows the calculated values of S; observed values are not 

 given because they cannot be very precisely determined. This is 



Fig. 5. Curves showing the (calculated) values of 5 in 0.52 ii XaCl, 0.278 ii 

 CaClo, and in mixtures of these (the figures attached to the curves show the 

 molecular strength of CaCli in the solution). The cun'es show the values cal- 

 culated from constants obtained by trial, which are given in Table II. The 

 abscissae represent the time of exposure to the toxic solution. The value of 5 

 at the start is in aU cases 2.7. 



^° The values of + 10 for solutions containing 2.44 and 15.0 per cent CaCIo 

 differ sKghtly from those given in a former paper (Osterhout, W. J. \'., J. Gen. 

 Physiol., 1920-21, iii, 15) for the reason that the cur\-es here presented include a 

 larger series of experiments. 10 is added to the value of because the base line 

 is taken as 10, just as in the case of M. 



