DISEASES OF SWINE AND OTHER ANIMALS. 329 
for the full development of all the other lesions. It fully demonstrates 
the preservation of the poison in a covered building at a temperature 
below the freezing point. 
Perhaps the most important experiments conducted by Dr. Law were 
_ those relating to the inoculation of other animals than swine with the 
virus and morbid products of pigs suffering with the plague, and the 
transmission of the disease from these animals back to healthy hogs. 
A merino wether, a tame rabbit, and a Newfoundland puppy were in- 
oculated with blood and pleural fluid containing numerous actively 
moving bacteria, taken from the right ventricle and pleure of a pig 
that had died of the fever the same morning. Next day the temperature 
of all three was elevated. In the puppy it became normal on the third 
day, but on the eighth day a large abscess formed in the seat of inoe- 
ulation and burst. The rabbit had elevated temperature for eight days, 
lost appetite, became weak and purged, and its blood contained myriads 
of the characteristic bacteria. The wether had his temperature raised 
for an equal length of time, and had bacteria in his blood, though not 
so abundantly as in that of the rabbit. The sheep and rabbit had each 
been unsuccessfully inoculated on two former occasions with the blood 
of sick pigs, in which no moving bacteria had been detected. Subse- 
quently, after two inoculations with questionable results, made with the 
blood of sick pigs in which no microzymes had been observed, Dr. Law 
succeeded in inoculating a rabbit with the pleural effusion of a pig that 
had died the night, before, and in which were numerous actively moving 
bacteria. Next day the rabbit was very feverish and quite ill, and con- 
tinued so for twenty-two days, when it was killed and showed lesions in 
many respects resembling those of the sick pigs. The blood of the rab- 
bit contained active microzymes like those of the pig. On the fourth 
day of sickness the blood of the rabbit containing bacteria was inocu- 
lated on a healthy pig, but for fifteen days the pig showed no signs of 
illness. It was then remoculated, but this time with the discharge from 
an open sore which had formed over an engorgement in the groin of the 
rabbit. Illness set in on the third day thereafter and continued for ten 
days, when the pig was destroyed and found to present the lesions of 
the disease in a moderate degree. A second pig, Inoculated with frozen 
matter which had been taken from the open sore on the rabbit’s groin, 
sickened on the thirteenth day thereafter, and remained ill for six days, 
when an imminent death was anticipated by destroying the animal. 
During life and after death it presented the phenomena of the plague in 
a very violent form. 
The results of these experiments have convinced Dr. Law, as they 
must convince others, that the rabbit is itself a victim of this disease, 
and that the poison can be reproduced and multiplied in the body of 
this animal and conveyed back with undiminished virulence to the pig. 
Dr. Klein had previously demonstrated the susceptibility of mice and 
guinea pigs to the disease. The rabbit, and still more the mouse, is a 
frequent visitor of hog pens and yards. The latter eats from the same 
feeding troughs with the pig, hides under the same litter, and runs con- 
stant risk of infection. Once infected, they may carry the disease to 
long distances. During the progress of severe attacks of the disease, 
their weakness and inability to escape will make them an easy prey to 
the omnivorous hog; and thus sick and dead alike will be devoured by 
the doomed swine. 
Dr. Law says that the infection of these rodents creates the strongest 
presumption that other genera of the same family may also contract the 
disease, and by virtue of an even closer relation to the pigs, may succeed 
