338 PROGRESS OP VETERINARY SCIENCE AND ART. 
I think it is useless insisting further on the above facts. 
I have clone so at lengthy because converse opinions have 
gained credence; and I have no hesitation in saying that they 
have anything but a salutary effect on the minds of young 
pathologists. It may still be necessary to say that, though 
the infectious nature of pleuro-pneumonia is much to be 
doubted, there is no question as to its, mostly, depending on 
epizootic influence; it may be more fatal when many causes 
concur for its extension, but, under all circumstances, the 
essential exciting agency operates in lowering the consti- 
tutional vigour, in diminishing the systemic tone, and the 
disease is of a low asthenic or typhous type. And, like in all 
plagues, it would appear that the most successful plan of 
treatment is that of supporting the vital powers during the 
long, and often, in itself, killing process of elimination of the 
morbid poison and morbid products. It is on this fact that 
success in adopting a tonic rather than an antiphlogistic 
system of treatment depends. 
The treatment first adopted in pleuro-pneumonia, especially 
by those of the Broussais school, was strictly antiphlogistic 
and revulsive ; and impressed with the belief that it is fatal 
to do anything but deplete and counter-irritate in inflam- 
matory disease, the first suggestion of a totally opposite plan, 
on which to manage cattle affected with the lung disease, 
was spoken of in a highly depreciating tone. Sundry ex- 
planations were given by those of the old school, who, per- 
suaded of the efficacy of sulphate of iron in such cases, 
argued that the modus operandi of certain agents, from 
various unaccountable causes, differed widely in different 
complaints, so that the diseases themselves might in some 
cases almost be classified according to the treatment com- 
ported than to their real nature. Busse, veterinary surgeon 
to the late Nicholas of Russia, somewhat supported such a 
notion, in a memoir he published in the Repertorium for 
January, 1852, and he warmly expresses himself as follows : 
ei But who, at any time, having with attention observed the 
enormous disorganization and after-products— especially the 
masses of false membranes, shreds and adhesions, the quan- 
tity of effused serum, and more particularly the fearful de- 
struction of the one or of the other lung, its consistence and 
weight, sometimes amounting to from thirty to sixty pounds — 
would, according to our precepts, look upon the sulphate or 
other preparation of iron, as the very agent calculated to 
overcome the morbid plasticity of the blood and the atony of 
the lungs ? Nevertheless, this is just the remedy which — con- 
trary to all the views and expectations of men, against all 
