458 Mr. W. Stiles and Dr. F. Kidd. Position of the 



Go7icentration Eq^iilibria reached in Salt Intake. " Heaping U'p " of Salts 

 in Living Tissue. Belation of External Concentration to Ratio of hvternal 

 to External Concentration at Eqnilihrium. 



From the results described in the preceding section it is possible to obtain 

 A'alues for the amount of salt absorbed in any case per unit volume of tissue 

 at any time. The values so obtained give us an expression for the " internal" 

 concentration of the salt. Hence we can obtain the ratio of the concen- 

 tration of the salt in the tissue to the concentration of the salt in the external 

 solution. 



The numbers are obtained on the assumption as before that the 

 decrease in the conductivity of the external solution is a measure of 

 the salt absorbed by the tissue. If the initial and final conductivities 

 are Ci and C2 and X the exosmosis into distilled water, and if V is the 

 volume of the external solution and v that of the tissue, then the ratio 

 of the concentration of the salt in the tissue to the concentration of the 



r/n .lX") CIV 



salt in the external solution = "-^ — I ^ — . As, for the reason already 



discussed, C2 is probably a higher value than actually represents the 



concentration of salt as compared with Ci the number "^-^) — ^2]^ 



, ,. ^, ,. internal concentration mi . ,. 



IS again a mmmium value 01 the ratio ■. — . ims ratio 



external concentration 



may be called the " absorption ratio." 



Table VII gives the values of the absorption ratios at the end of 

 each experiment for the different concentrations of the various salts 

 used. It is not clear, as the graphical representations given above show, 

 that equilibrium in absorption had been reached in all cases by this time. 

 The curves having as ordinates the final internal concentration and as 

 abscissae the final external concentration, correspond to the equation y = kc"^, 

 where y is the final internal concentration and c the final external concen- 

 tration, and k and m are constants. 



For this equation may be written in the form 



log V/ — m log e = log k, 



and plotting log y against log c for our results, straight lines are obtained 

 (figs. 5 and 6). 



Although the actual values of these absorption ratios as precise measure- 

 ments cannot be emphasized, the general conclusion which they indicate is 

 remarkable. 



