308 PERICARDITIS. 



and to the comparative silence of veterinary authors upon this 

 important subject. 



Diseases of the heart in this animal are not suspected by the 

 farrier, (shoeing-smith) or horseman ; yet they are by no means 

 of unfrequent occurrence. During the session of the Veterinary 

 College of Philadelphia for 1859-CO, the author had then op- 

 portunities of presenting to the class well-marked cases of disease 

 of this organ, as also one very interesting case of rupture of the 

 heart, or rather of 'the aorta, or great artery leading from the 

 heart, at the point where it leaves that important organ. The 

 latter case was that of a bay mare which had been used in an 

 oyster cart; she ate her feed at night as usual, in apparent good 

 health; and was found dead in her stall the next morning. 



PERICARDITIS. 



This disease, as its name implies, is an inflammation of the 

 pericardium, the bag or sac which surrounds the heart, and 

 known to butchers as the heart-bag. After death arising from 

 pleuritic affections effusions are quite commonly found within 

 this sac, which are attributed to the sympathy existing between 

 the pericardium and the pleura. The fluid is sometimes of a 

 bright yellow color, while at others it is of a turbid character 

 v^'ith considerable lymph floating in it, which collects in a mass 

 forming a thick layer upon the internal surface of the sac, 

 causing considerable thickening of its walls, and extending over 

 the heart in like manner ; adhesions between the two sometimes 

 take place. Percival mentions an instance in which this col- 

 lection was converted into a substance of the nature of gristle 

 of considerable thickness. This disease rarely exists alone, but 

 is of a secondary character. 



