ADYNAMI7E. 363 



and whole surface of the body become pale, and more or less 

 cold, according to the degree and duration of the paroxysm. 

 Very commonly at the beginning of this, and during its con- 

 tinuance, a cold sweat appears, and perhaps continues, on the 

 forehead as well as on some other parts of the body. During 

 the paroxysm, the animal functions, both of sense and motion, 

 are always in some degree impaired, and very often entirely sus- 

 pended. A paroxysm of syncope is often, after some time, spon- 

 taneously recovered from ; and this recovery is generally at- 

 tended with a sense of much anxiety about the heart. 



Fits of syncope are frequently attended with, or end in, vomit- 

 ing ; and sometimes with convulsions, or an epileptic fit. 



MCLXXI V. These are the phenomena in this disease ; and, 

 from every view of the greatest part of them, there cannot be a 

 doubt, that the proximate cause of this disease is a very weak 

 or a total ceasing of the action of the heart. But it will be a 

 very difficult matter to explain in what manner the several re- 

 mote causes operate in producing the proximate cause. This, 

 however, I shall attempt, though with that diffidence which be- 

 comes me in attempting a subject that has not hitherto been 

 treated with much success. 



The remote causes of syncope may, in the first place, be 

 referred to two general heads. The one is, of those causes 

 existing and acting in the brain, or in parts of the body re- 

 mote from the heart, but acting upon it by the intervention 

 of the brain. The other general head of the remote causes of 

 syncope is of those existing in the heart itself, or in parts very 

 immediately connected with it, and thereby acting more direct- 

 ly upon it in producing this disease. 



MCLXXV. In entering upon the consideration of the first 

 set of those causes (MCLXXI V.), I must assume a proposition 

 which I suppose to be fully established in Physiology. It is 

 this : That though the muscular fibres of the heart be endowed 

 with a certain degree of inherent power, they are still, for such 

 action as is necessary to the motion of the blood, very con- 

 stantly dependent upon a nervous power sent into them from 

 the brain. At least this is evident, that there are certain powers 

 acting primarily, and perhaps only in the brain, which influence 



