DISEASES OF SWINE AND OTHER ANIMALS. 381 
accident in contact with a raw surface, will produce disease as surely as 
did the quills in my inoculations. My own observations in this respect 
have been more than corroborated by one of Professor Axe, of the Royal 
Veterinary College, London. He produced the disease by inoculating 
from ivory points on which the cutaneous exudation had been dried up 
for the long period of twenty-six days. 
That the poison can be preserved even in the liquid state when the 
germs of putrefaction are excluded, may beinferred from my successful 
inogulations with blood that had been kept in an isolation apparatus, at 
the ordinary body temperature, for the period of eleven days. As directly 
to the point is the cultivation of the poison in aqueous humor for seven 
days, by Klein, and its subsequent successful inoculation. This experi- 
ment of Klein is, however, possessed of vastly greater importance, inas- 
much as by it it was first shown that the poison can be cultivated and 
indefinitely increased out of the animal body as well as in it. On seven 
successive days he inoculated seven successive portions of aqueous humor 
with as much of the inoculated liquid of the previous day as would ad- 
here to the point of a needle, the first having been similarly inoculated 
from the sick pig. From the cultivations of the fifth and seventh days, 
respectively, a drop was taken and two pigs were successfully inoculated 
therewith. In the cultivation of each day were found myriads of bacillus, 
but no other organization, and thus Klein was the first to show that the 
bacillus is the probable cause of the disease. Had there been no repro- 
duction and increase of the poison, it must have been rendered incon- 
ceivably dilute, an approximate ratio of the poison added to the first 
day’s cultivation, and that added to the last, being about as 1 is to 
1,000,000,000,000,000,000. That such a dilution could be operative seems 
utterly incredible, and as modern research shows that virulence resides 
not in simple liquids, but in the solid particles contained in them, and 
as the only definite organisms in the\cultivation liquids were the bacilli, 
it seems inevitable that these are the active cause of the disease. But 
if so, they cannot only be preserved, but increased in suitable fluids out- 
side the animal body. It is true they disappear when the active organ- 
isms of ordinary putrefaction (bacteriwm termo) become numerous, but 
they are not necessarily destroyed. From what we know of the life of 
these mycrophytes it is to be feared that so far as the bacillus has ad- 
vanced to the production of spores, it will be preserved in a dormant 
state, like so many dried seeds, until conditions favorable to its growth 
shall transpire. On the other hand it may be recollected that my at- 
tempts to propagate the disease from a putrefying bowel failed, so that 
further observation is wanted before we can say that the bacillus or its 
spores are preserved in a septic liquid. However that may be, the pos- 
sibility of its increase in a non-septic normal fluid is an additional argu- 
ment for the total destruction of all diseased pigs and morbid products. 
In the case of high-priced pigs, where expense is no object, and where 
the patients can be kept in thoroughly disinfected pens, under the most 
rigid seclusion, treatment may sometimes be commendable; but in the 
case of common herds, and as viewed from the standpoint of the great- 
est good to the greatest umber, there can be no question at all that the 
treatment of the sick is the most ruinous policy, while the most stringent 
measures for the extinction of the poison is the only economical one. 
The universal experience of veterinarians supports this conclusion, and 
nearly every European government has now reached the same conviction, 
and absolutely prevent the preservation and treatment of the victims of 
those fatal contagious diseases which most threaten their flocks and 
herds. 
