192 Manual of Veterinary 31k-rohiolo(jy. 



ill the last stage of charbon. It is especially by its 

 secretions that the bacteridium acts upon the organ- 

 ism. The nature of these substances is as yet im- 

 perfectly understood, but their action is demonstrated 

 by the following experiment: M.Chauveau transfused 

 to a healthy sheep a large quantity of blood coming 

 from a sheep affected with charbon, and, as a conse- 

 quence, noticed the development of the general symp- 

 toms of the disease. This immediate result can only 

 be explained as a chemical poisoning, an opinion 

 which was, moreover, confirmed by the microscopic 

 examination, which showed the disappearance of the 

 bacilli from the transfused sheep. It is to this in- 

 toxication that we must ascribe the phenomena of 

 nervous depression or temporary excitement, which 

 are so marked in charbonous subjects. 



Charbonous blood filtered through porcelain acts on 

 the red corpuscles of normal blood, rendering them 

 ■viscid and glutinous. This property is communicated 

 to it by the substances secreted by the charbon bacilli 

 and it explains the peculiar alteration of the blood 

 in this disease. 



Finally, the bacilli act mechanically ; on account of 

 their number and the abnormal viscidity of the blood, 

 they form plugs in the interior of the capillary ves- 

 sels, thus occasioning blood stases and superficial and 

 deep hemorrhages. This is undoubtedly the cause of 

 the final passage of the bacteridia into the milk, 

 urine, and through the placenta ; it is also the cause 

 of the large and characteristic sw^elling of the spleen, 

 as well as of the hemorrhages and general circulatory 

 disturbance. 



Attenuation. Vaccinations. — The virulence of char- 



