B22 PROTECTIVE INOCULATIONS. 
and sterilized for an hour in a steam sterilizer. This liquid remains 
sterile on account of the presence of mercuric chloride, and may be 
preserved a long time without losing its activity. The dose is from 
0.3 to 0.5 cubic centimetre, which is diluted to three cubic centimetres 
with carbolic acid water (0.5-per-cent solution). The diluted solu- 
tion may also be kept a long time without losing its activity. 
Bonome and Vivaldi (1892) have tested the action of mallein ob- 
tained by precipitation with alcohol upon various animals. Guinea- 
pigs were found to resist comparatively large doses (ten to fifteen 
milligrammes), while rabbits and cats were more sensitive to the 
toxic action. In guinea-pigs and rabbits infected with glanders ba- 
cilli very small doses had a favorable influence upon the progress of 
the infection, and in healthy guinea-pigs a certain degree of immunity 
was induced by the repeated injection of small doses. 
In a subsequent paper (1894) Bonome reports that he has had 
favorable results in the treatment of chronic glanders in man by doses 
of ;'5 to 1; cubic centimetre. The first dose is said to have caused 
an elevation of temperature, headache, polyuria, etc., but upon re- 
peating the dose after two or three days a decided improvement of 
the general symptoms followed. 
Chenot and Picq (1892) claim to have cured glanders in guinea-pigs 
by injections of blood serum from the ox, which animal has an im- 
munity from the disease. They also state that the blood serum of . 
the ox is germicidal for the glanders bacillus. Guinea-pigs treated 
with ox serum, either before or after infection, recovered in seven 
cases out of ten. When inoculated with very virulent cultures, which 
usually killed these animals in five days, the animals are said to have 
survived from twenty-one to forty-two days. 
Bonome (1894) reports his success in curing infected guinea-pigs 
by means of filtered cultures made in the blood serum of the ox. He 
was not, however, successful in accomplishing this result with mallein 
made in the usual way. 
HOG CHOLERA. 
The experiments thus far made with reference to protective inocu- 
lations against hog cholera have not given very satisfactory results. 
Selander and Metchnikoff have reported success in immunizing rab- 
bits, but according to Smith their experiments were made with the 
bacillus of swine plague, and not with that of hog cholera as they 
supposed. The following conclusions have been formulated by Smith 
as a result of his extended experiments: 
“1. It is possible to produce immunity toward hog-cholera and swine- 
