BY DR. OSCAR KATZ. 525 



treatment. The latter was found dead at 9.50 p.m., same day, it 

 having died between 9 p.m. and that time (i.e., between 8 and 9 

 hours after inoculation). (Result of P.M. examination^ "chicken- 

 cholera.") 



The tame rabbit appeared somewhat indisposed on the evening of the 

 same day, and on the morning of the following day. After that time 

 it behaved as lively as usual, ready to eat any food given to it. But 

 this time again an abscess developed itself at the place of inoculation, 

 without having, however, any fatal effects on its bearer. The abscess 

 discharging again copious quantities of pus, had almost completely 

 healed up in the middle of June ; on the other hand, under the skin to the 

 left of the seat of the abscess, a hard, freely movable nodule of about 

 nutmeg- shape and -size was noticed. When seen, June 29th, the wound 

 had completely healed up and the nodule disappeared. 



Other Experiments on Rahhits regarding Immunisation. 



It is known that Pasteur succeeded in conferring immunity 

 against infection by virulent chicken-cholera bacteria, on fowls 

 which had previously been inoculated with liquids obtained by 

 filtering virulent broth-cultures of those bacteria through a 

 Pasteur-Chamberland filter. The bacteria being thus eliminated, 

 the efiect produced by the filtrate must be ascribed to soluble 

 substances resulting from the growth of the bacteria in the culture- 



fluid. 



The results of a few similar experiments on rabbits are published 

 by Prof. P. Foa and Dr. A. Bonome, in Turin.* By repeated 

 injections of filtered broth-cultures of the chicken-cholera microbes 

 into a rabbit, and subsequently of active culture, the death of the 

 animal from chicken-cholera occurred at a considerably later date 

 than that of a control-rabbit. By injecting successively larger 

 doses of filtrate, and more frequently, a rabbit was rendered 

 altogether insusceptible to a subsequent inoculation with such 

 active microbes as were able to kill a fresh rabbit after a certain 

 time. 



* Ueber Schutzimpfungen. Zeitschrift fur Hygiene, Band V., Heft 3, 

 1889, p. 423. 



