Acute Pleurisy in the Horse. Pleuritis. 245 



Dupuy injected two drachms of oxalic acid dissolved in three 

 ounces of water. Symptoms of. pleurisy at once came on, with 

 the friction sound characteristic of its early stages. Next day 

 friction sound had ceased and evidence of effusion existed. The 

 same experiment repeated on several horses showed that if killed 

 at any period subsequently to this, considerable exudation had 

 already taken place. In one horse in which the disease was of 

 50 hours' standing the chest contained 43 pints of citrine-colored 

 fluid, and abundance of yellow, thick, false membrane enveloping 

 the costal and pulmonary pleurae. 



Hamont injected seven ounces of a weak solution of tartaric 

 acid into the left pleural sac, repeated the injection next morning 

 and destroyed the horse twenty minutes afterward. The chest 

 opened immediately showed a small amount of liquid on the 

 affected side, and the pleura injected and reddened. 



Delafond made twenty-tw^o experiments with the same general 

 result. 



Percivall found recent adhesions between the lungs and side so 

 early as seventeen hours after the commencement of the pleurisy. 



Andral injected rabbits with acetic acid and in nineteen hours 

 found in the injected pleura soft, thin, false membranes traversed 

 by red anastomosing lines, and in certain cases a serous or puri- 

 form fluid. 



W. Williams found a false membrane formed twenty-fours after 

 the injection of the irritant. 



St. Cyr in a series of 43 experimental and casual pleurisies in 

 horses, found that in a very few hours there was marked local 

 congestion and swelling of the pleura speedily followed by the 

 formation of soft, pulpy, friable false membranes, largely amor- 

 phous and granular but impregnated with many cells and nuclei. 

 These adhere feebly to the pleura but may accumulate with pro- 

 digious rapidity so as to cover in three or four days the whole 

 pleural surface on one or both sides. The attendant serous effu- 

 sion was bloody, turbid, or lactescent. The pleural surface under 

 the false membrane was highly vascular and studded with fragile, 

 red conical elevations projecting into the membrane. Exception- 

 ally the sub-serous connective tissue became the seat of exudation 

 as well. 



From the sixth to the ninth day the false membranes began to 



