REVIEW. 
205 
The appearance of the malady under such circumstances is evi- 
dently referable to the presence of the fresh-comer. Repeat 
this experiment,” he says, “ a thousand times, and a thousand 
times you will obtain the same result.” 
“ Make the reverse experiment : isolate the fresh-comer as 
soon as he arrives; and, supposing that distemper should make 
its appearance, he alone will prove the subject of it. 
“ Again, let a team of horses,” he says, “ perform a forced 
journey, and through it, or through extreme wet weather, catch 
cold, and breed the distemper ; and let them cohabit with other 
teams, and the last will contract the disorder, notwithstanding 
they have not been subjected to any of the determining causes 
of it. 
“ The communicated distemper will assume different forms in 
the different animals it falls upon, notwithstanding the identity 
of the source whence it has arisen ; but this is a character which 
is common, as far as it goes, to every enzootic and epizootic 
disease. In one horse it will shew itself only in a discharge 
from the nose. In another, it will manifest itself in abscess 
under the jaw. In a third, these two forms will be combined. 
In a fourth, the disease will display all its forms with a cortege 
of symptoms of malignant distemper, either confined to the head 
or extending down to the lungs. Lastly, in another subject, 
the distemper will from the first assume the characters of chro- 
nic catarrh or nasal gleet. 
“These several varieties of one and the same affection are 
dependent upon conditions peculiar to individuals at the mo- 
ment of their infection. The mode of transmission of distemper 
is through contact, mediate or immediate, as well as through 
the medium of the surrounding air. The contagion of distem- 
per consists, according to M. Charlier, in a virus fixed or vola- 
tile ; and the propagation of this last will, at all times, depend 
upon certain influences : during cold weather, for example, it 
will be less manifest than during warm. 
“ A horse in a sweat, exposed to the influence of air charged 
with contagious miasms, will be more disposed to take the dis- 
ease than were he subjected to the same influence at a time 
when the functions of his skin were not aroused into action.” 
[To be continued.] 
F f 
VOL. XXIV. 
