BY C. J. POUND. IX 



in a perfect state of health. Its rapid course is only e<]ualle(l hy 

 its malignity, few animals, especially cattle and sheep, recovering 

 from its destructive inttiience. In the year 18.50 Davaine and 

 Eayer made the very important discovery of the bacillus Anthracis, 

 which is the immediate cause of Anthrax ; and although they 

 describe its relative size to the red corpuscles, and the fact that it 

 is not possessed of any definite movement, as occurring in the 

 blood of animals having died from splenic fever, they fiiiled to 

 recognise its real importance. In 1868, however, Davaine resumed 

 his investigations, which he had discontinued thirteen (1:5) years 

 before, respecting the influence of the filamentous bodies which 

 he had at that time noticed in the blood of animals which had 

 died from splenic fever. These researches were carrie<l on for 

 many years, till, in 1878, he asserted positively that these rods, 

 which he called " Bacteridie du C'harbon," were the essential 

 cause of this malignant disease, they were constant in tlic blood 

 of animals that died from Anthrax, and that such lilood when 

 filtered and inoculated in animals had no effect. 



Since that time our ac(juaintance Avith these bacilli has l)een 

 greatly extended by Eobert Koch and others, and our knowledge 

 of their life history confirmed by the most exhaustive and careful 

 investigation. These researches, which can only Ije carried out 

 by the aid of the microscope, are still continuing, and we shall 

 see later on to what wonderful results in combating the symptoms 

 to which their presence gives rise ; but we must briefly examine 

 a little more in detail how the disease is communicable from 

 animal to animal. If the blood of a diseased animal be examined 

 a little before or immediately iifter death, the vegetative rods of 

 Bacillus Anthracis are easily found by means of a suitable micro- 

 scope. Now if the smallest «]uantity of such blood is introduced 

 into the tissues of another animal capable of taking the disease, 

 the inoculated animal becomes infected and almost certainly 

 succumbs ; and if the blood of the second animal be similarly 

 examined this also will be found densely populated witli the same 

 hacilli. We thus see that the disease is accompanied l)y the 

 enormous multiplication of the micro-organisms within the system 

 of the infected animal, and that the disease may V»e indeiinilely 

 communicated from one aninnil to another ; l)ut we mav also 



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