42 LECTURES ON IMMUNITY 



a very high degree if acids or bases are added to their 

 solutions. Madsen and Famulener have, for instance, 

 investigated the rate of decomposition of a solution of 

 vibriolysin, which contained so little sodium hydrate that 

 it was 0.005 n. in alkalinity. They found the above 

 figures : 



The constants of the reaction of this monomolecular 

 process are found to be 0.0313 at 48 and 0.012 at 46.5 C. 

 This gives a value of /x = 128,000, or just the same value 

 as that noted for vibriolysin without the addition of alkali. 

 This correspondence may perhaps not be of so great an 

 interest as it seems at first, since the solution of vibriolysin 

 is in itself a little alkaline. . But it is not probable that its 

 alkalinity is due to sodium hydrate, but chiefly to weaker 

 organic bases, and therefore the coincidence of n in the 

 two different cases is still remarkable. 



Other substances also exert an influence upon the de- 

 struction of vibriolysin and tetanolysin, although to a much 

 less degree than solutions of the alkalies. Of these, am- 

 monia has a less influence than sodium hydrate, but the dif- 

 ference is by far not so accentuated that it would be possible 

 to invoke the action of the OH ions. Thus, for instance, 

 the reaction-constant of vibriolysin, which at 46.2 reaches 

 the value 0.0066 (per min.) is increased to 0.081 if 3.4 c.c. 

 of I n. NaOH are present in 100 c.c. of the liquid, and to 

 about 0.075 in the presence of the equivalent quantity of 

 ammonia. An addition of hydrochloric acid gave different 

 results according to its quantity. The first addition di- 

 minished the constant of reaction, which reached a mini- 

 mum 0.00052 in the presence of 4.25 c.c. i n. HC1 in 100 c.c. 

 of the liquid. With larger amounts the reaction-constant 



