206 TUBERCULOSIS. 



conclusion that perlsucht was due to the same virus as 

 tubercle. He concluded that the virus of tubercle was 

 comparable in its mode of action with that of other infectious 

 diseases. 



These views, however, aroused a storm of opposition from 

 all sides. The opposition was at first chiefly on theoretical 

 grounds, but later also from experimental results. Investi- 

 gators who repeated Villemin's experiments obtained similar 

 results so far as the production of tuberculosis by tubercular 

 material was concerned, but many found that tuberculosis 

 also followed inoculation with non-tubercular material (such 

 as pus from pysemic abscesses, portions of decomposed 

 tissue, etc.), and even by the mere introduction of setons. 

 The general opinion came to be strongly against the existence 

 in tubercle of an infective agent of specific nature, and along 

 with this there prevailed great confusion as to the distinction 

 between tubercular and non-tubercular lesions. 



Armanni, in 1873, by scarification of the cornea and 

 inoculation with tubercular material, produced in that 

 situation a small tubercular ulcer, which was afterwards 

 followed by general tuberculosis. Such a result he 

 found never followed inoculation with non-tubercular 

 material. But it was the work of Cohnheim and Salo- 

 monsen along similar lines which was chiefly instrumental 

 in altering the general opinion with regard to the non- 

 specific nature of a tubercular virus. By inoculation of 

 the anterior chamber of the eye of rabbits with tubercular 

 material they found that in many cases the results of irrita- 

 tion soon disappeared, but that after a period of incubation, 

 usually about twenty-five days, small tubercular nodules 

 appeared in the iris ; and afterwards the disease gradually 

 spread, leading to a tubercular disorganisation of the globe 

 of the eye. Later, the lymphatic glands became involved, 

 and finally the animal died of acute tuberculosis. The 

 question remained as to the nature of the virus the 

 specific character of which was thus established, and this 

 question was answered by the work of Koch. 



The announcement of the discovery of the tubercle 



