73 



tlie course of the preceding pages, ma}^ be either 

 absolute and permanent, or it may be only temporary, 

 as in the case of the two medical students, who after 

 apparently proving themselves to be immune against 

 scarlet fever, ultimately contracted it during a period 

 of depression of their vital powers, with the result 

 that one of them died.^' 



There is also found here and there an immunity 

 of a limited application — viz., that possessed by an 

 individual tissue against some definite bacillus. This 

 form hardly comes within the scope of our present 

 consideration and can only be said to apply indirectly 

 to our subject, but I here give it a special notice 

 because an instance of it has been unconsciously and 

 inconsequently used in the course of a premature 

 attempt to show the readers of a certain Magazine, 

 (which for some reason or other eschews modern 

 science), how little dependence need be placed on my 

 conclusions, and in what urgent need I personally 

 stood of being told of even the existence of any kind 

 of immunity at all. In this communication, which 

 can only be described as being somewhat of the lucus 

 « ?id7?z/?^r^?/^^ order, my critic hastened to tell us that 

 the tetanus bacillus is frequently found in the 

 intestines of the horse without his suffering any in- 

 convenience from its presence " excepting under 

 certain conditions." Seeing that the normal home of 

 this bacillus is on and near the surface of the ground, 

 especially that which is not frequently being broken 

 up, it would indeed be extraordinary if it were not 

 found in the intestines of an animal who may any day 

 be observed to pull up occasional mouthfuls of grass 

 by the roots and eat the whole lot, earth and all. It 

 would, I say, be in the nature of a veritable miracle, 

 were it not almost habitually found in the cavities 

 specified, when we consider that it can be isolated 



Green. Pathology and Morbid Anatomy, gth Edit., page 286. 



