526 MANUAL OF MODERN FARRIERY 



disease to the human subject from the lower animal, 

 for reasons which are self-apparent, the field of opera- 

 tion is a shut one, but light is indirectly thrown upon 

 this point by experiments, having for their object the 

 transmission of the disease from the human subject to 

 the lower animals. A considerable number of ex- 

 periments in this direction have been made, and all 

 with the same result, but time and space will only 

 permit of one example being given in detail. 



The experiment to which I now refer was con- 

 ducted by Professor Edgar M. Crookshank, King's 

 College, London, and reads as follows : — " I obtained 

 sputum containing numerous bacilli from an advanced 

 case of phthisis. The sputum was shaken up with 

 sterilised salt solution and injected into the peritoneal 

 cavity. A few weeks afterwards the calf showed signs 

 of illness. The animal looked dull, did not feed well, 

 had a slight cough, and showed less inclination to move 

 about than usual. 



These symptoms gradually increased, and death 

 occurred forty-two days after inoculation. Extensive 

 lesions were discovered at the post-mortem examina- 

 tion. The mesentery was adherent to the abdominal 

 wall at the seat of the inoculation, and to the rumen; 

 the liver was adherent to the diaphragm. There was 

 extensive tubercular deposit at the seat of inoculation, 

 and an abscess the size of a walnut. Extending over 

 the mesentery from this point, there were hundreds of 

 wart-like, fleshy new growths, some quite irregular in 

 form, others spherical or button-shaped. 



There were similar deposits on the under surface 

 of the liver, on the spleen, in the gastro-splenic 

 omentum, and on the peritoneal surface of the 

 diaphragm. On microscopical examination of sections, 

 extremely minute tubercles were found to be dis- 



