CHAPTER XV. 



Anthrax. 



The Bacillus Anthracis — Early Observations — PoUender— Davaine — Koch 

 — Pasteur — Methods of Examination — Appearances of Bacillus under 

 Different Conditions — SRpre Formation — Non-spore Bearing Bacilli — 

 The Vitality of the Bacillus and of the Spores — Cultivation Experi- 

 ments — Cover-glass Preparations — Inoculations into Animals — Methods 

 of Infection — Anatomical Characters of Malignant Pustule — Animals 

 Affected — Spores not formed in the Living Body — The Disposal of 

 Anthrax Carcases — Various Disinfectants^ — Pathogenic and Sapro- 

 phytic Anthrax — Buchner's Experiments on Anthrax Bacillus and 

 Bacillus Subtilis — Hueppe and Wood's Experiments. 



Anthrax, or splenic fever, is perhaps the best known of all 

 the specific infective bacillary diseases. The Bacillus An- 

 thracis, compared with other pathogenic organisms, is of 

 very considerable size ; it is from 5/* to zon long, and i toi. 5/i 

 broad. It multiplies with very great rapidity in the blood of 

 certain animals, and may be very easily cultivated outside 

 the body ; in consequence of these features it was the first 

 organism that was proved definitely to be associated with a 

 specific disease, and it was certainly one of the first to be 

 recognized as occurring in both animals and in man. 



In 1849, PoUender, and in 1850, Rayer and Davaine 

 described these organisms as occurring in the blood of animals 

 that had succumbed to splenic fever; then again, in 1857, 

 Brauell, examining the blood of a man affected with anthrax, 

 found this same bacillus. 



Later, as already described, Pasteur's wonderful experiments 

 on fermentation were published, and these led Davaine, in 

 1863, to commence a series of observations on anthrax, which, 

 carried on until 1873, gave everything but absolute proof that 

 the anthrax bacillus was the actual exciting cause of this malig- 

 nant disease. This proof, however, was not supplied until 1 876, 

 when Koch, who had then been working at the subject for 



