LECTURES ON IMMUNITY 



As will be seen from these figures, these poisons do not 

 follow nearly as closely as tetanolysin and ammonia the 

 rule that the square root of the degree of haemolysis is 

 proportional to the concentration. The quotient of these 

 two magnitudes is tabulated under K. In general the 

 greater the velocity of reaction the more marked is the 

 deviation from the said rule. At about 10 per cent 

 the haemolysis increases relatively more rapidly with the 

 concentration than at other degrees of haemolysis. There- 

 fore the measurement of the quantity of poison present by 

 means of the haemolytic determination has the greatest 

 exactitude in the neighbourhood of this point. 



Different strong monovalent bases act in equivalent 

 quantities nearly to the same degree upon the blood- 

 corpuscles. The divalent bases Ca(OH) 2 and Ba(OH) 2 

 seem to give some solid precipitate in the erythrocytes, 

 which hinders measurements, at least at higher concentra- 

 tions. The haemolysis observed is then nearly independent 

 of the quantity of base added. Ammonia also has nearly 

 the same strength of action as equivalent quantities of the 

 strong monovalent bases. Sometimes (for low concentra- 

 tions of blood) its action is a little less, in other cases (at 



