386 CARDITIS. 



process of active inflammation. Leblanc refers to the fre- 

 quent observation of true carditis, and then says that the 

 best circumstances to observe its lesions are immediately 

 around the seat of any injury to the heart, or when an 

 abscess develops in the walls, and lastly, when other altera- 

 tions take place, such as deposits of lymph, &c. But the 

 very vagueness of the symptoms furnished by Leblanc, indi- 

 cate that he is not acquainted with a primary inflammatory 

 disease involving the heart's substance. The very circum- 

 stance that his cases of carditis are declared by him as by no 

 means incurable, prove that the heart is exempt from such a 

 disease. 



PERICARDITIS. 



The serous covering of the heart is liable to inflammation 

 more frequently than other heart structures. Pericarditis is 

 seen with equal frequency in all our domestic animals. It 

 occurs often as a primary or idiopathic disease, and, at other 

 times, it is a complication in constitutional and contagious 

 disorders. Its characteristic lesions are seen in pleuro- 

 pneumonia in cattle, in influenza in the horse, and in rheu- 

 matism. Its causes are numerous, and usually allied to those 

 which induce acute diseases of the respiratory organs. Damp, 

 cold, alternations of temperature, are all favourable to its 

 development. 



The symptoms of pericarditis are often obscure, and it is not 

 to be wondered at, when we consider how little the region 

 of the heart is exposed in the lower animals for auscultation. 

 The heavy shoulder, firmly applied on either side of the keel- 

 shaped thorax, precludes any very accurate observations 

 such as the human physician has opportunities of making. 

 If veterinary works are consulted on this subject, it will be 

 found that the information they furnish is very limited. I 



