276 



BACILLI PATHOGENIC IN MAN. 



Cultivation 

 experiments 

 and experi- 

 ments on 

 animals. 



been as yet in vain. Even after being kept for fourteen 

 days on solidified blood serum at 37 C. no, growth can 

 be observed. In like manner, attempts to communicate 

 the disease to animals have met with great difficulties, 

 although on several occasions a slight spread of the 

 leprous process from the particles introduced to the 

 normal tissue has been seen. Thus Damsch observed, 

 in the case of two rabbits after inoculation of a piece of 

 a tumour into the anterior chamber of the eye, that 

 after five weeks in both animals the iris and the ciliary 

 body were infiltrated with dense lines of large cells con- 

 taining bacilli, and that deposits appeared on Descemet's 

 membrane, and on the anterior capsule of the lens, which 

 consisted of round cells containing bacilli. In like 

 manner a successful attempt has been made to inoculate 

 the leprous tumours into the peritoneal cavity, and under 

 the skin of two cats. In the latter case the cats were 

 killed after 120 days ; on making an examination it was 

 seen that the tumour had become flattened and shrunk in 

 the subcutaneous tissue, and that it was surrounded and 

 fixed to the skin by a brownish tissue of new formation, 

 which contained numerous cells filled with leprosy 

 bacilli. Vossius repeated the experiment of introducing 

 pieces of tumour into the anterior chamber of the eye in 

 rabbits, and likewise observed multiplication of the 

 leprosy bacilli, and their penetration into the iris and 

 cornea. But in none of the cases did the process spread 

 further, nor was the clinical picture of leprosy produced ; 

 ; -and in many other experiments even the infection of the 

 neighbouring tissue has failed. Thus attempts which 

 were made by Damsch to inoculate the disease sub- 

 cutaneously in mice and rabbits, by Vidal in a pig, by 

 Kobner in frogs, eels, &c., were entirely without result. 

 In the case of man also, the spread of the disease by 

 infection is extremely rare, and is evidently only possible 

 under very special predisposing circumstances. 



In spite of the great blanks in our knowledge with 

 regard to the leprosy bacilli, we must look on these 

 organisms as undoubtedly the cause of the disease, 

 because they occur constantly and exclusively in this 



