16S 
D. E. SALMON. 
in right nostril by rubbing the suspension into superficial scarifi¬ 
cations. 
On the same clay, inoculated horse No. 2 by hypodermic in¬ 
jection of 1 c.c. of suspension in the left nostril, and by rubbing 
the suspension into superficial scarifications in the right nostril. 
In all cases the point selected for inoculation was that at 
which the natural ulcers were most frequently located. 
The inoculation by means of scarifications produced no effect 
in either horse. In two days the scarifications were healed and 
no lesions developed subsequently. 
The hypodermic injection of the suspension caused a small, 
tense swelling in both horses at the point of inoculation, ending 
in the formation of a small abscess and the escape of a few drops 
of pus, in No. 2 on October 9 and in No. 1 on October 12. Both 
were entirely healed by October 15, without any indication of 
ulceration. 
From these experiments, it was concluded that there was no 
virus on the surface or in the floor of these ulcers which, when 
inoculated, would cause the development of similar lesions in 
other animals. 
Experiment to determine if the ulcers healed readily when 
the horses zvere removed from the pastures and stabled. —As it 
was alleged by the farmers that the ulcers would begin to heal 
as soon as the horses were removed from the pastures and fed 
on good hay, it was deemed advisable to test the assertion by 
actual experiment. Accordingly, a horse in which very large 
and acute ulcers had just developed in both nostrils was taken 
from the Lappin ranch, 1.5 miles east of the smelter, October 2, 
and placed in a stable on the Para ranch, 4 miles north of the 
smelter, where it could be observed daily. It was fed on hay 
which was raised outside of the smoke zone. At the time the 
experiment was begun, there was no discharge from the ulcers, 
but they were very sensitive, and where the crusts were removed 
the ulcerated surface was seen to be covered with a very thin, 
whitish layer of pus. Six days later (October 8), the ulcers 
showed marked improvement. The crusts were beginning to 
