8l ANTHRAX 



the diseased tissues or liquids oi Bacterium anthracis, by an 

 enlarged spleen, blood extravasations and by local gangrene. 

 It usually occurs in fhe acute form. 



§ 72. History. Anthrax is among the oldest of the 

 known infectious diseases of animals. Descriptions of epi- 

 demics and epizootics of this disease are given by Homer, 

 Plutarch, Livy and other writers before the Christian Era. 

 The Arab physicians designated it as "Persian Fire." Exten- 

 sive outbreaks are mentioned in the literature of the fifteenth, 

 sixteenth, seventeenth, eighteenth and nineteenth centuries. 

 Chabert pointed out in 1780 that the various kinds or forms 

 of disease, which had previously been described as independ- 

 ent affections, were all one disease. As late as 1805, Kausch 

 gave a good description of anthrax but denied its contagious- 

 ness. Delafond and Gerlach investigated very thoroughly 

 ovine anthrax in 1845 and its contagiousness was experiment- 

 ally shown by Gerlach. In 1850, Heusinger published a very 

 comprehensive treatise on anthrax, which dealt at length with 

 its history and geographical distribution. 



Much new information concerning the nature of anthrax 

 was acquired during the fifth decade of the last century. In 

 1855, Pollander announced the discovery, which he first made 

 in 1849, of minute unbranched rod shaped bodies in the blood 

 of cattle dead of anthrax. Davaine observed similar bodies in 

 1850. Then followed a long series of observations and some- 

 what controversial discussions on the bacterial origin of the 

 disease, culminating in 1875 by Robert Koch's careful descrip- 

 tion of the morphology of its specific organism including the 

 spore formation. Cohn, however, seems to have been the 

 first to have called the organism a Bacillus and to have sus- 

 pected the existence of spores. Toussaint, in 1880, and 

 Pasteur in 1881, published results of investigations directed 

 toward protective inoculation. Since that time, the literature 

 on the cause, morbid anatomy and prevention of anthrax has 

 become very extensive. 



§ 73. Geographical distribution. Anthrax is a widely 

 disseminated disease. The continent of Europe has perhaps 

 suffered most from its ravages. It occurs, also, in Northern. 



