ACTION ON ANIMALS 127 



with ether. The result was that on evaporation of the 

 alcoholic filtrate we obtained a sticky residue which it 

 was utterly impossible to pulverize or to weigh. We were 

 compelled, therefore, to content ourselves with evaporating 

 it to a sticky mass, which was then immediately dissolved 

 in water. The solution of the substance thus prepared 

 was . very poisonous, but, as a rule, took from one to two 

 hours or even longer to bring about a fatal result. The 

 animals showed the roughening of the coat and the stupor 

 characteristic of the living and dead bacillus, but not as a 

 rule seen in the case 'of the soluble poison. ..Furthermore, 

 the majority of the animals showed during life unmistakable 

 signs of peritoneal inflammation. They died in convulsions. 

 At autopsy an intense hemorrhagic peritonitis was present, 

 which was particularly prominent in the omentum and 

 mesentery, and hemorrhage was often present in the cap- 

 sules of the liver and the spleen. From the fact that death 

 was slower in these cases and that the symptoms were 

 more like those seen after inoculation with the living bacillus, 

 we are inclined to believe that in this instance the poison, 

 although split off from the bacillus itself, still exists in 

 combination with some other cell group, and that it is 

 essential that this combination be broken up before the 

 poison can be set free and can act on the body cell. 



Another interesting fact in this connection is furnished 

 by the action of the poison in solutions which have been 

 rendered strongly alkaline by the addition of sodium bicar- 

 bonate. As has been previously stated, the aqueous solu- 

 tions of the poison are slightly acid in reaction, and in order 

 to avoid the irritative effects which might follow their 

 injection into the peritoneal cavity, they were neutralized 

 or rendered slightly alkaline by the addition of sodium 

 bicarbonate. 1 At first no attempt was made to secure 

 perfect neutralization, with the result that sometimes 

 we were making use of neutral, while again slightly or 



1 The precaution of neutralizing the soluble poison, when properly 

 prepared, is unnecessary as it has no appreciable irritative action. 



