TUBERCULOSIS. 389 



on the thirty-second day, and all the rest were 

 killed on the thirty-fifth day. All had extensive 

 tuberculosis, and the Bacillus tuberculosis was found 

 in the tubercles of the lungs, and of various 

 organs. The two guinea-pigs not inoculated re- 

 mained healthy. 



In another experiment four rabbits were taken. 

 Into the eye of one pure blood-serum was injected ; 

 the point of a syringe containing tubercle bacilli in 

 blood-serum was introduced into the eye of a sec- 

 ond. These were from a series of cultures carried 

 out for 132 days. In this case the piston was not 

 moved ; but the same material was injected into 

 the eye of rabbit No. 3, and of rabbit No. 4. 

 The animals were killed on the thirtieth day, and 

 the following result noted : Rabbit No. 1 remained 

 healthy ; rabbit No. 2 had typical tuberculosis of 

 the iris, and the nearest lymphatic glands were 

 swollen and infiltrated with yellowish nodules ; 

 but the lungs and other organs were free from 

 tubercles. Rabbits Nos. 3 and 4 had iritis and 

 tuberculosis of the lungs. 



The presence of Koch's bacilli in tuberculous 

 sputum has now been confirmed by numerous ob- 

 servers in various parts of the world ; and the 

 comparatively few failures to find the bacillus 

 which have been reported by expert manipulators 

 since the method of Ehrlich was published, are 

 easily accounted for in other ways than upon the 

 supposition that cases of tuberculosis occur in 

 which no bacilli are found. Nevertheless we must 



