236 



THE ACUTE PNEUMONIAS 



produce a general septicaemia ; whereas in more immune species 

 there is an acute local reaction at the point of inoculation, and 

 if the latter be in the lung, then there may result pneumonia, 

 which, of course, is merely a local acute inflammation occurring 

 in a special tissue, but identical in essential pathology with an 

 inflammatory reaction in any other part of the body. When a 

 dose of pneumococci sufficient to kill a rabbit is injected sub- 







FIG. 69. Capsulated pueumococcus in blood taken from the heart 

 of a rabbit, dead after inoculation with pneumonic sputum. 



Dried film, fixed with corrosive sublimate. Stained with oarbol- 

 fuchsin and partly decolorised, x 1000. 



cutaneously in the human subject, it gives rise to a local inflam- 

 matory swelling with redness and slight rise of temperature, all 

 of which pass off in a few days. It is therefore justifiable to 

 suppose that man occupies an intermediate place in the scale of 

 susceptibility, probably between the dog and the sheep, and 

 that when the pneumococcus gains an entrance to his lungs the 

 local reaction in the form of pneumonia occurs. In this con- 

 nection the occurrence of manifestations of general infection 

 associated with pneumonia in man is of the highest import- 



