104 
w. zuir.L. 
pensable, both for the good of animals and of man. For if mjui 
benefits, so do animals; a discovery which averts disease in one 
will probably protect others. Every advance in knowledge is a 
benefit to all. 
To prohibit resort to experiment would be at once to doom 
animals, which we are bound to protect, to the endurance through 
all time of diseases which might otherwise be overcome. This 
has been our experience in all diseases which have not yet been 
capable of experimental study, and we may reasonably hope that 
the future will greatly extend the scope of our field of action. 
One thing is, however, sure: Experiment is the only possible 
avenue by which such success can be reached. 
CONTAGIOUS PLEURO-PNEUMONIA. 
Thesis presented by W. Zuill, D.V.S., before the University of Pennsylvania, 
Medical Department. 
{Continued from page 67.) 
Case No. 3. 
With the single exception of cough, this animal might have 
been considered perfectly healthy. She was so extremely wild, 
that she had to be shot. There was not the slightest ocular demon¬ 
stration of disease. On opening the pleural cavity a condition 
very similar, but if possible, more aggravated than in case No. 1 was 
seen. But the lesions were older and more chronic; there was 
less effusion in the chest cavity, the fibrous exudate was more or¬ 
ganized and not so easily detached as in the other case. 
The central portion of the lung was much more advanced 
than was either the apex or base. On section through the centre 
of the organ, it was found that the inflammatory condition had 
gone on to suppuration, forming an immense abscess, filled with 
pus and pieces of lung tissue, the largest of which weighed about 
five or six pounds. This large abscess was surrounded by a band 
of dense connective tissue, in some places over one inch thick. 
The superior and lateral external walls of this abcess were agglu¬ 
tinated to the adjacent chest walls, indicating that it would sooner 
or Pater have discharged itself, possibly through the costal parietics. 
