190 THE HUMAN HEART. 



becomes transferred to this wonderful organ. Again, every muscle 

 that moves, whether in breathing, standing, walking, manual labor? 

 eating, or in whatever other way, throws the venous blood forcibly 

 and newly upon the heart, and affects its condition. Of this we have 

 evidence in the operation of bleeding, in which, when the arm is 

 tied to prevent the blood from returning through the veins to the 

 heart, and the fist is rapidly doubled, or even the fingers worked 

 about, the current squirts in forcible jets from the opened vein. 

 What then must be the squirt of the venous blood heartward, in a 

 wrestle of the whole body, or during a rapid run ? Moreover, where 

 the frame is enfeebled by long disease, and the patient is bed- ridden, 

 the motion of rising into the erect position sends dangerous jets to 

 the heart, in many cases oppressing it beyond recovery, and leading 

 to swoon and death. And where there is disorder of the heart, the 

 muscular exertion of undressing and stepping into bed, will cause 

 prolonged anguish, until the heart's circulation is equilibrated. 

 These are proofs that the state of the circulation affects that of the 

 heart, and that the movements of the body affect the circulation; 

 and we have already seen that the mind is continually playing upon 

 the capillaries, and the capillaries referring their disturbances to the 

 heart. The question arises, Is there any provision in the heart to 

 enable it to maintain its own constancy in the midst of the fluctua- 

 tions of the blood, and to make it the head, ratio or balance, as well 

 as the heart of the too mobile circulation ? 



This problem has not been unnoticed by physiologists, and Mr. 

 Abernethy in particular endeavored to connect the solution of one 

 part of it with the foramina of Thebesius. It is here that Sweden- 

 borg's doctrine of these foramina and the coronaries, finds its strong- 

 est present attestations. According to this view, the varying 

 quantities of blood returned upon the heart find an outlet through 

 the walls of the heart itself, and equilibrium is thus maintained by 

 the coronary vessels ; so that the heart plus the coronaries equals 

 all the forces of the circulation; while the heart minus the corona- 

 ries is a comparatively regular force uninfluenced by the general 

 state of the system. Were it not for such provision, the heart would 

 be at the mercy of extraneous influences; the most important organ 

 of the trunk would have no stability, but would in the end yield, 



