Microhlc Diseases Individually Considered. 191 



face. It is asserted that tliis migration is chiefly due 

 to the agency of earth-worms. We know that these 

 worms, in excavating the passages through which they 

 wander, swallow a certain quantity of earth which 

 they then expel in the form of tortuous rolls ; we also 

 know that they make regular nocturnal peregrina- 

 tions to the surface of the soil in order to feed on the 

 herhage. Now, M. Pasteur has found, in these little 

 rolls of earth deposited above a grave containing a 

 charbonous carcase, the spores or germ corpuscles 

 of the disease. These spores do not necessarily always 

 remain limited to the part of the field on which they 

 have been deposited ; they may be more or less widely 

 disseminated by winds, and more especially by water. 

 If we admit as established the possibility of the 

 multipUcation of the bacilli of charbon in swampy 

 soil we can readily account for the persistence of the 

 disease in certain localities. 



The charbon bacilli may penetrate into the blood 

 directly or indirectly; in this last case they first make 

 their way into the tissues, multiply there, and excite 

 an inflammatory engorgement, then gain the lym- 

 phatic glands and, finally, the blood. They then act 

 by a complex mechanism. By reason of their aerobic 

 character they rob the blood of part of its oxygen and 

 thus give rise to asphyxia. This asphyxiating action, 

 however, is contradicted by the investigations of 

 M. Chauveauwho has demonstrated the presence of a 

 normal proportion of oxygen in the blood of a sheep 



the blood or organs of buried cadavers [Feser, Kitasato, Kitt) ; they 

 are found, however, on the surface of these bodies where they are 

 soiled with blood, excretions, etc., and also in the digestive canal 

 both before and after death. — D.] 



