114 



XXXIV. ON THE CAUSE OF THE BEATINGS OF THE HEART. 



The cause of the rhythmical movements of the heart has been 

 heretofore unknown. I believe I have discovered it. 



Before exposing my theory and the facts upon which it is 

 grounded, I will show that the theories put forward until now 

 are not correct. 



There are three theories only which are worthy of examina- 

 tion : 1st, that of Haller ; 2d, that of Carpenter ; 3d, that of 

 Budge, Schiff, and others. 



Haller has been very near the truth in admitting that the 

 beatings of the heart were excited by the blood. His error has 

 been an error loci. He thought that the blood acted in the 

 cavities of the heart. It is not so ; and it is known that the 

 heart may continue to beat after all the blood has been drawn 

 out of its cavities. 



The doctrine of Carpenter* is a very simple and remarkable 

 one. He believes that the muscular fibres may act without hav- 

 ing been excited. A muscle, says he, may be compared to the 

 electric jar, and become so charged with motility , (or motor force,) 

 as to execute spontaneous contractions ; and elsewhere, " It is not 

 very difficult to conceive that the ordinary rhythmical movements 

 of the heart may be due to a simple excess of this motility, which 

 is continually being supplied by the nutritive operations, and is 

 as constantly discharging itself in contractile action." Carpenter 

 believes that the reason for which the heart presents spontaneous 

 contractions while the other muscles do not, (at least ordinarily,) 

 is, that there is a higher degree of motility in the heart. He 

 considers as very important the facts I have discovered, that 

 many other muscles besides the heart may present rhythmical 

 movements. He thinks that these facts show there is a tendency 

 to rhythmical movements in the muscles themselves, altogether 



greater quantity then than usual. I believe that this increase results from 

 the excitation of the nervous system, and, in some measure, perhaps, from 

 a direct action of black blood on the capillaries of the glands. The urinary 

 secretion may also be changed in asphyxia, and not only then the urine 

 may contain sugar, as Alvaro Reynoso has found, but also albumen. 



*See his Principles of Human Physiology, American edition, by F. G. 

 Smith. Philadelphia, 1853. pp. 130 to 132, 319, 325, and 471-72. 



