SCIENCE IN MEDICINE 245 



treatment of this condition. A recent clinical paper by Netter 

 confirms the value of calcium as a prophylactic for these 

 undesirable complications. 



Briefly it may be said, as regards the use of anti-bacterial 

 sera in the treatment of bacterial infections, that only too 

 frequently there has been a tendency to guess at the bacterial 

 nature of some cases on rule-of-thumb knowledge, with the 

 result that a so-called anti-serum, boldly professing to counter- 

 act the class of bacteria hypothetically assumed to be the 

 offenders, is injected into the unfortunate patients in conjectural 

 doses with mechanical regularity. 



Active humanity. — When a bacterial vaccine is introduced 

 into an animal the immediate effect on the blood is a lowering 

 of its resisting power to the micro-organism in question. This 

 phase is followed by one during which protective substances 



Fig. 1. — An Inoculation Curve. 



are elaborated in response to the infection, and the resisting 

 power of the blood becomes greater than the normal resistance. 

 A gradual return to the normal then occurs (fig. 1). This train 

 of events, which follows upon a single inoculation, was first 

 fully described by Wright, and was built up on the study of 

 the effects of the inoculation of bacterial vaccine made first in 

 connection with typhoid inoculation. To the various phases 

 this author has given the names "the negative phase," "the 

 positive phase," and " the phase of maintained high level." 



Next as regards a series of inoculations. It is possible to 

 give subsequent inoculations during any of these three phases, 

 and the result in each case will be different and must be 

 described : 



(1) Inoculation during the negative phase. In this case a 

 cumulative action in the direction of the negative phase is 

 produced (fig. 2). 



