298 THE LAWS OF ORGANIC 



be materially modified by the natural conforma- 

 tion of the system, or any of its parts ; by the 

 complexity of the disease, the number of .organs 

 affected; and, lastly, by the re-action of many 

 causes which we cannot correctly appreciate. 



CCCXXV. It is not by any means easy to 

 point out, in a precise manner, the operation of 

 these different causes in inducing palpitation. 

 We observe, in the greater number of instances, 

 that the breathing is short and hurried by gentle 

 exercise, or from slight mental emotion, when the 

 system is subjected to any of these physical con- 

 ditions ; and we are compelled to acknowledge 

 that the circulation of the blood is dependent on 

 respiration, and is also influenced by every change 

 or disorder occurring in the latter. Therefore, it 

 can scarcely be called in question, that in pro- 

 portion as we render the performance of a func- 

 tion delicate, we augment the liability to derange- 

 ments in organs whose every action is regulated 

 by the character of that function. It is on this 

 account that palpitation of the heart and syncope 

 are occasional symptoms in pregnancy, and in 

 other cases in which the con tents of the abdomen 

 diminish the free descent of the diaphragm. 



CCCXXVI. We have at times palpitation of 

 the heart, or a predisposition to it, in many inter- 

 nal diseases, the operation of which cannot be re- 

 ferred to any physical state, acting either on the 

 diaphragm or directly on any organ connected 



