COXTAGIOUS DISEASES OF DOMESTICATED AKBIALS. 427 



succession witli autlirax poison from the guinea-pig ^ntll steadily- 

 decreasing res^ilts, and then a filth time with blood from an anthrax 

 sheep; but he survived all, and did vrell. 



A six-months' calf -was inoculated with anthrax fluids that had passed 

 through the guinea-pig and been afterward cultivated in an albuminous 

 fluid for four generations of the poison, and nine days later, with blood 

 direct from the spleen of an anthrax guinea-pig ; but a recovery ensued 

 in both case§. An old emaciated and pregnant cow inoculated with 

 the blood of an anthrax guinea pig died on the fourth day. Age, de- 

 bility, and pregnancy were charged with the- result. Finally, a sheep 

 was inoculated with the anthrax pois(m that had been passed through 

 the guinea-pig, and thereafter cultivated to the fourth generation in an 

 albuminous fluid ; but the result was not fatal. It should be added, 

 that the anthrax liquids used on all these animals were tested by con- 

 temporary inoculations on guinea-pigs and mice, and invariably with 

 fatal effect. 



As a sequel to these, it should be noticed that Pasteur claims to have 

 mitigated the poison of chicken cholera and the bacteridian disease by 

 cultivation in different fluids ; and to have conveyed it back to the fowl, 

 not only without producing a fatal result, but with the effect of ren- 

 dering the system of the fowl unimiDressible by the same poison for the 

 future. 



The close analogy between these two diseases and the swine fever in 

 their mode of causation by bacteria suggests very strongly a common 

 pathology for all ; and as the mode of reproduction and development of 

 the different bacteria which respectively cause the three plagues is 

 probably the same or closely allied, the promise is held out that the 

 specific swine fever may be anticipated and prevented, as the above 

 experiments imply that the other two affections can be. 



Nor are the above-named observers alone in their tentative results. 

 Wernich, Bauman, and ISTeucki find it highly probable that bacteria are 

 destroyed by certain products of the putrefaction to which they them- 

 selves have given rise ; so that the continued existence or propagation 

 of a specific bacterium in an individual system is rendered difficult or 

 impossible by the i)revious generation of that microphyte in the same 

 animal body. ^ 



But at this point still another question arises. In view of the mild 

 effects produced by inoculating the cultivated virus (Nos. 8 and 10, 

 present report), may the poison of this disease not be mitigated by cul- 

 tivating it in particular solutions, so that when inoculated on the pig 

 it wiU come short of destroying life, and yet prove a protection against 

 the ordinary fatal form of the poison ? Klein's cultivations were made 

 in the aqueous humor of the rabbit, and though he has not stated how 

 violent were the inoculated cases, yet it would not be surprising if they 

 proved fatal, as did our own cases of inoculation from the rabbit. My 

 inoculations with the swine-plague virus preserved in bran j>roduced 

 severe symptoms and a fatal result, in keeping with the virulence 

 of anthrax \Trus which had been preserved in a similar medium. In 

 my other cases, inoculated with virulent egg-albumen (iSTo. 8) and am- 

 moniated milk (No. 10), the resulting disease was moderate, and did 

 not threaten fatal result. 



While, therefore, it cannot be confidently affirmed that we can at 

 will induce a mild form of this affection which shall protect the system 

 against a severe one, we have in the above facts a sufficient warrant 

 and inducement to carry this experimental investigation to a certain 

 and reliable conclusion. It remains for the experimental pathologist to 



