50 KENNEL DISEASES. 
CHAPTER III. 
ACUTE PLEURISY. 
BETWEEN the lungs and chest walls, on each side, there is a cavity which is 
lined by an exceedingly delicate membrane called the pleura. The free surface 
of this is smooth and polished, and kept moistened by a thin, watery fluid, which 
prevents friction as the lungs alternately fill and empty. 
In acute inflammation of this membrane, which constitutes acute pleurisy, the 
fluid in question disappears, and the smooth surfaces become dry and roughened ; 
and as a natural consequence, there is pain when they come in contact, as they 
must with every inspiration. The dryness, however, rarely exists longer than 
twenty-four hours, when there occurs an effusion of a watery huid, known as 
serum, into the cavity, and this for the time being separates the pleura. The 
pain is then much less severe or has wholly disappeared. 
The quantity of effusion varies in different cases ; and while it might be suffi- 
cient to compress the lung and render it temporarily valueless, rarely is it of 
considerable amount. 
Where the disease pursues from the first a favorable course, the absorption 
commences in a few days after the fluid has reached its maximum, and recovery 
occurs within two or three weeks. Absorption may, however, be considerably 
delayed, and if so for a month or more the pleurisy is then chronic. The fluid 
may even in time change to pus; in which event the disease is no longer pleu- 
risy, but empyema. 
Acute pleurisy may be produced by a severe blow upon the chest, and espe- 
cially if the ribs are fractured. It is also quite certain to speedily follow wounds 
that have penetrated the chest walls. But in most instances it occurs in conse- 
quence of sudden exposure to cold, or is due to extension of inflammation from 
the lungs or adjacent organs or parts, as in pneumonia, pericarditis, peritonitis; 
hepatitis, etc. 
Attacks are usually sudden, and the first noticeable signs are, shivering, indi- 
cative of a chill; some fever; small, weak, and quickened pulse; restlessness, 
with movements that suggest that the patients are stiff and sore; appetite capri- 
cious or wholly wanting; nose hot and dry; eyes reddened and watery; lining of 
the mouth dry, reddened, and congested, with urgent thirst; bowels and kidneys 
inactive; dry, short, hacking, and evidently painful cough; quite rapid breath- 
ing, which may also be termed superficial, restrained and jerking, as the inspira- 
