SrORADIC PNEUMONIA ANI) CONTAGIOUS PLEURO-PNEUMONIA. 525 
Some believe in its existence and have described its differential 
characters ; others have denied it entirely or have mixed it with the 
contagious disease which, according to them, is but an accidental 
variation of it; then others again, without giving settled opinions, 
pretend that the cases of sporadic disease were not sufficiently 
evident to conclude as to its presence. 
In France, Cruzel, Leblanc and Zundel are of the first opinion ; 
in Germany, Kreulzer, Hildebrand, Spinola and Furstenberg not 
only accept it, but claim that it is quite common. The last named 
author has even indicated some characteristic and necropsical 
symptoms, which distinguish it from the contagious disease. 
But other German authors and practitioners have doubted the 
value of the symptoms given by Furstenberg, and Lydtin espec¬ 
ially has said that the lesions mentioned by him were those of 
pleuro-pneumonia contagiosa. 
From recent discussions upon this subject, it is evident that 
the opinions differ yet essentially. While H. Bouley, Camille 
Leblanc, Trasbot and Cagny admit that the lungs of ruminants 
can be the seat of true contagious inflammation; others, Sanson, 
Nocard and Weber, consider the cases recorded as errors of diag¬ 
nosis, and say that the pretended cases of sporadic disease were 
isolated pleuro-pneumonia, pulmonary congestion, vernicular 
bronchitis, pulmonary echynoccoci, etc., etc. 
Tins variety of opinion can explain to a certain extent the 
differences which still exist in some minds in relation to the con¬ 
tagious or non-contagious nature of pleuro-pneumonia, and of the 
efficiency of preventive inoculation. 
Those who do not admit of the sporadic disease, may, indeed, 
have in some cases where they have unknowingly met it,.made 
inoculations, powerless to grant immunity; and it can be under - 
stood that in the presence of these negative results, and of the 
aptitude of the inoculated to take the contagious disease, their 
faith in inoculation may have been shaken. 
It is also in the presence of some cases of sporadic pneumonia 
that some practitioners have concluded to the want of the conta¬ 
gious power of pleuro-pneumonia, from that of the propagation 
in the observed cases. 
