578 
COM PTE RENDU OF THE 
7. The termination of pulmonary inflammation in gangrene is 
very common in the horse. The frequency of this fatal complica- 
tion arises, principally, from two causes : on the one side, the per- 
fect functional structure of that organ in which the sanguineous and 
aerial canals are multiplied to such an extent, that the cellular 
tissue, the basis of all plastic structure, becomes, in manner of 
speaking, rarefied, and, at the period when inflammation causes 
the stagnation of blood in the capillaries, does not present sub- 
stance sufficient to enable it to re-act against the liquid mass infil- 
trated into its air-cells ; and, again, the natural fluidity of the blood 
of the horse takes a very leading part in the production of gangrene. 
At the time when the blood becomes stagnated in the capillaries, 
and subsequently in the larger vessels, a great quantity of serosity 
becomes separated from the condensed fibrine and albumen, fil- 
trating through the cellular texture of the lungs, macerating it, as 
it were, and destroying in it all plastic power. 
The air acting upon this mass of liquid and animal matter shut 
up in a sort of organised net-work, whose vitality is thus, in a 
measure, extinguished, quickly causes it to undergo a putrid de- 
composition, rapidly transforming the substance of the lungs and 
the clots of blood it contains into a soft deliquescent substance of 
a reddish-green colour, holding in suspension consistent masses of 
a yellow amorphous matter, which are the fibrinous clots of disco- 
loured blood. Gangrene of the lungs of the horse is then, properly 
speaking, neither more nor less than the putrefaction of the organ, 
and of the fluids contained in it, purely from contact with the air. 
8. The alterations produced by gangrene of the lungs have fre- 
quently been taken for chronic changes of structure. The yellow 
amorphous matter floating in the gangrenous liquidity has been 
considered to be tuberculous deposit : this is an error which atten- 
tive observation will soon rectify. The alterations we have been 
describing may, in sound-constitutioned horses, be produced in a 
very short period of time. The very rapidity of their formation 
is, in fact, a proof of the soundness of the lungs in which they are 
developed. If the organ prove the seat of former indurations, or 
of tuberculous cavities, those parts, modified by chronic inflamma- 
tion, would, from their greater degree of density, be more capable 
of resisting the process of putrefaction, and often be found unaf- 
fected in the midst of the gangrenous dissolution, in such rare cases 
wherein gangrene has attacked long-diseased lungs. 
9. The gangrenous odour of the expired air, and the gurgling 
sounds apparent on auscultating at the level of the softened parts, 
are the principal pathognomonic signs of the supervention of this 
termination of pneumonia. 
10. Suppuration very rapidly takes place in the lungs, whether 
