PNEUMONIA. 131 
rarely encountered ; such a result accords with the knowledge gained by 
anatomical investigation concerning the structure of or the substance of 
the lung. The bronchial tubes constitute a large portion of these organs, 
but their disease is termed bronchitis. The pleura covers the lungs, 
but its inflammation is called pleurisy. The blood is affected during all 
disorders, but the vessels themselves are rarely implicated ; involvement 
of the absorbents constitutes glanders and farcy. Yet, when the tubes, 
covering, veins, arteries, and absorbents are abstracted, there remains 
only cellular tissue; that structure is not apt to take on inflammation, 
and when it is so implicated, the inflammation of cellular tissue is re- 
garded as rheumatism: consequently, there remains only a species of 
general disorder of all the constituents to stand for pneumonia. 
Horses supposed to have perished from pneumonia, not unfrequently, 
when examined after death, present hydrothorax or dropsy of the chest; 
thus proving the pleura to have been affected. However, such vivid 
descriptions of pneumonia are bequeathed us by our ancestors, that we 
are, to a certain degree, overpowered by the authority of assertion. Too 
many are actually overawed by the positiveness of the dead; thus, in 
many instances, influenza is treated as inflammation of the lungs ; dropsy 
of the chest, brought on by weakness, naturally ensues. 
When acute pneumonia (as it is called, which really represents a sub- 
acute disorder of all the contents of the lungs) does occur, it is rather 
lingering in its development ; the breathing is labored and slightly 
accelerated ; the pulse is less increased than would be expected; the 
artery is full, and the beat seems 
driven by some hidden force 
through a gelatinous obstacle; 
it bulges out, and then all is 
still for an interval, after which 
the operation is repeated. The 
horse has lost all spirit, indeed, 
a considerable portion of its con- 
sciousness has evidently depart- 
ed; it stands as though from 
giddiness it feared to fall; its 
legs are separated and strained 
outward to the furthest limit. 
The head and ears are de- 
. 5 , . 5 THE POSITION ASSUMED BY THE HORSE DURING AN 
jected ; the coat rough ; the es AGGRAVATED ATTACK OF PNEUMONIA. 
tremities cold; the body without 
warmth; the visible membranes discolored, and the bowels costive; in 
short, the animal appears oppressed hy some heavy misfortune. Feeling 
