238 SUSCEPTIBILITY AND IMMUNITY. 



serumalbumin, and that it is a purely chemical process." They 

 state that when the germicidal power is neutralized by heat it may 

 be restored by the addition of an alkali. Buclmer repeated the ex- 

 periments of Emmerich and his associates and obtained similar re- 

 sults, but interprets them differently. According to him the serum 

 does not regain its germicidal power, but after the addition of an 

 alkali and subsequent dialyzing the nutritive value of the serum is so 

 diminished that the bacteria do not develop in it. 



Pane (1892) has made experiments which give additional weight 

 to the assumption that the alkalinity of the blood is an important 

 factor in accounting for immunity. He states that carbonate of 

 soda, dissolved in water, in the proportion of 1:3,000, has a de- 

 cided germicidal action upon the anthrax bacillus, equal to that of 

 the blood serum of the rabbit. And that when rabbit serum is com- 

 pletely neutralized it no longer has any injurious action on anthrax 

 bacilli. 



Zagari and Innocente (1892) also arrived at the conclusion that 

 the diminished resistance to anthrax infection resulting from curare 

 poisoning in frogs, and from chloral or alcohol in dogs (Platania), in 

 fowls as a result of starvation (Canalis and Morpurgo), in white 

 mice as a result of fatigue (Charin and Roger) , is, in fact, due to 

 diminished alkalinity of the blood, which they found to correspond 

 with the increased susceptibility resulting from the causes men- 

 tioned. 



Buchner (1892) states that several of the ammonium salts, and 

 especially ammonium sulphate, cause an increase in the germicidal 

 action of blood serum, and also increase its resistance to the neutral- 

 izing effects of heat. The experiments of Pansini and Calabrese 

 (1894) show, on the contrary, that the addition of uric acid to blood 

 serum diminishes its bactericidal activity, as does also the presence 

 of glucose. That certain infectious diseases are especially virulent 

 in persons suffering from diabetes is a frequently repeated clinical 

 observation. 



Van Fodor has shown by experiment that the injection of an 

 alkali into the circulation of a rabbit increases its resistance to 

 anthrax infection and the germicidal activity of its blood serum. 

 The same bacteriologist has found that when a rabbit is infected 

 with anthrax, the alkalinity of its blood is notably increased during 

 the first twenty-four hours, when we may suppose that the powers 

 of nature are brought to bear to resist the invading parasite, and that 

 after this time it rapidly diminishes. Ten hours after infection (by 

 subcutaneous inoculation?) the alkalinity of the blood had increased 

 21.5 per cent. Shortly before the death of the animal a diminution 

 of 26.3 per cent was noted. This diminution was observed in thirty- 



