CHEMICAL EQUILIBRIA 115 



we should investigate the neutralization of ammonia 

 regarded as a lysin, i.e. measured by its haemolytic 

 activity, by means of boracic acid, and of sodium 

 hydrate by hydrochloric acid. 



The result of the experiments was in perfect 

 accordance with what I expected. The simplest 

 case is the neutralization of one equivalent of 

 sodium hydrate by hydrochloric acid. The salt 

 formed is absolutely innocuous. Say that we have 

 oi normal solutions of NaOH and HC1 ; if we add 

 o-i cc. of the alkali to 10 cc. of a 2-5 per cent 

 emulsion of red blood-corpuscles, this dose gives a 

 certain degree of haemolysis (after 2 hours at 37 C). 

 Now we mix 05 cc. HC1 with 1 cc. NaOH and 

 investigate which quantity of this mixture gives the 

 same degree of haemolysis. Evidently in 1-5 cc. of 

 the mixture there is as much free sodium hydrate 

 as in 05 cc. of the original solution. We must 

 therefore now take 03 cc. of the mixture for ob- 

 taining the said effect, and so forth. The diagram 

 (Fig. 31) representing this behaviour is a straight 

 line, which cuts the ^-axis at 1 corresponding to 

 addition of a quantity of acid equivalent to the 

 quantity of base used. In reality the line of 

 neutralization cuts the ^-axis a little before, because 

 the corpuscles sustain a certain minimal quantity 

 of free alkali before any haemolysis is observed. 

 If we add more acid we observe a similar small 

 region of acidity which does not attack the corpuscles, 

 and then haemolysis occurs again and the haemolytic 

 power of the solution is proportional to the excess 



