216 



ELECTROCHEMISTRY 



If, taking the solution of 8 per cent serum-proteins in neutral 

 0.01 N KCl as the zero-point on the axis of the abscissae, we 

 measure off to the right of this point the concentrations of acid 

 in which the proteins were dissolved, and to the left of this point 

 the concentrations of alkali in which they were dissolved and 

 plot the values of log Ch+ given in the above table, we obtain 

 a curve,* by interpolation from which it is readily found that in 

 passing from the reaction 0.37 X 10~^ H+ to the reaction 1.00 X 

 10"'^ H+, 100 cc. of an 8 per cent solution of the serum protein 

 neutrahzes 2.25 cc. of N/10 HCl, that is 22.5 cc, or about one- 

 fifth of its own volume of A^/100 HCl. According to Henderson, 

 in passing through the same range of H+ concentrations the 

 bicarbonates in 100 cc. of blood will neutralize the equivalent 

 of 100 cc. of N/100 HCl. Hence we must conclude that, between 

 the reactions mentioned, the proteins of the serum are only one- 

 fifth as efficient in maintaining its neutrality as the bicarbonates. 

 To the neutralizing power of the serum proteins must be added, 

 in circulating plasma, that of the fibrinogen. This is, however, 

 probably very slight, since only a very small percentage of fibrin- 

 ogen is contained in the blood. 



* For the form of the curve see my original communication (58). 



