26 
FRANK S. BILLINGS 
The result obtained then had only this value: It completely 
demonstrated that the majority of hogs that have been through 
swine plague from natural infection will not have the disease a 
second time, even after very severe tests, and therefore that pre¬ 
vention by vaccination is possible. 
With regard to the two inoculated pigs that died from the 
effects of exposure, I will claim nothing, but will mention that 
the Hon. S. W. Burnham, senator from Lancaster, who so kindly 
placed the infected herd at my disposal to do anything I pleased 
with, remarked “ that those small pigs will not live anyway if se¬ 
vere weather comes on.” I also vaccinated some forty of Mr. 
Burnham’s hogs, and very severely; those hogs came through and 
have since thrived better than any other hogs on the place. 
Whether this fact was indeed due to the inoculation or not cannot 
be positively asserted, but there is a favorable suspicion that it 
was. 
I wish to publicly experss my thank Mr. Burnham for the ex¬ 
tremely kind and liberal support he gave me in my work, placing, 
as he did, his man and everything I desired at my disposal. 
TEST EXPERIMENTS. 
The next thing was to try the vaccine test over again. To 
this end fresh pigs numbered with tags in the ears were selected; 
their numbers were 41, 42, 43, 44, 45, 46, 47. Nos. 42, 43, 44, 
45, 46, 47 were first inoculated with four fluid grammes—in the 
inside of the hind leg—of a mild vaccine upon November 4,1886, 
and again with six fluid grammes of a stronger vaccine upon Nov¬ 
ember 27. While thrown off their feed, and somewhat lame, with 
some heat and swelling in the inside of the hind leg, they did not 
seem to suffer very much. No. 41, which was the same pig as 
number 20 in the previous list that had been fed with pure potato 
cultivations, was inoculated with the same amount of vaccine as 
the others (six fluid grammes), on the 27th of November. 
December 27 Nos. 41 and 44 were inoculated with six fluid 
grammes of a fresh culture (second generation) made from the 
spleen of a hog from a very virulent outbreak at Valparaiso, Neb. 
These hogs were inoculated directly into the abdominal cavity. 
On the same day and at the same time Nos. 47 and 46 were inocu¬ 
lated with the same material in the inside of the hind leg. 
