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its adhering to the neighbouring parts. The principal use of the peri' 

 cardium, is to fix the heart in its place, to prevents its being displaced 

 into other parts of the chest, which could not happen, without occasion- 

 ing a fatal disorder in the circulation. If, after having laid open the 

 chest of a living animal, by raising the sternum, an incision is made into 

 the pericardium, the heart protrudes through the opening, and moves to 

 the right and left by bending itself on the origin of the large vessels ; the 

 course of the blood is then intercepted, and the animal threatened with 

 immediate suffocation. 



In man, the heart is placed nearly towards the union of the upper 

 third of the body, with the lower two-thirds; it is, therefore, nearer to 

 the upper parts; it holds them under a more immediate controul, and as 

 that organ keeps up the action of all the rest, by the blood which it sends 

 into them, the parts above the diaphragm have much more vitality than 

 the parts beneath. The skin of the upper part of the body, and espe- 

 cially of the face, has more colour, and is warmer than that of the lower 

 parts; the phenomena of diseases come on more rapidly in the upper 

 parts; they are, however, less liable to put on a chronic character. 



The bulk of the heart, compared to that of other parts, is larger in the 

 foetus, than in the child that has breathed; in short men, than in those of 

 high stature. The heart is likewise larger, the stronger, and more pow- 

 erful in courageous animals than in weak and timid creatures. 



This is the first instance of a moral quality depending on a physical 

 disposition of parts ; it is one of the most striking proofs of the influence 

 of the moral character of man on his physical nature. Courage arises 

 out of the consciousness of strength, and the latter is in proportion to 

 the activity with which the heart propels the blood towards all the or- 

 gans. The inward sensation occasioned by the afflux of the blood, is the 

 more lively, and the better felt, when the heart is powerful. It is on that 

 account that some passions, for example, anger, by increasing the ac- 

 tion of the heart, increase a hundred fold both the strength and courage, 

 while fear produces an opposite effect. Every being that is feeble, is 

 timorous, shuns danger, because an inward feeling warns him, that he 

 does not possess sufficient strength to resist it. It may perhaps be ob- 

 jected, that some animals, as the turkey cock and the ostrich, possess 

 less courage than the least bird of prey, that the ox has less than the lion 

 and other carnivorous animals. What has been said does not apply to 

 the absolute, but to the relative size of the heart. Now, though the heart 

 of a hawk be absolutely smaller than that of a turkey cock, it is neverthe- 

 less larger, in proportion to the other parts of the animal. Besides, the 

 bird of prey, like the other carnivorous animals, in part owes his courage 

 to the strength of his weapons of offence. 



Another objection, more specious, but not better founded, is drawn 

 from the courage manifested, on certain occasions, by the most timid 

 animals, for example, by the hen in protecting her young ; from the 

 courage with which other animals pressed by hunger or lust, surmount 

 all obstacles, but particularly from the heroic valour of men of the most 

 feeble bodies. All these facts, however, are only proofs of the influence 

 of the mind on the body. In civilized man, the prejudices of honour, in- 

 terested considerations, and a thousand other circumstances, degrade 

 the natural inclinations of man, so as to make a coward of one whose 

 strength is such as would induce him to brave all kinds of dangers, while 

 on the other hand, men whose organization should render them most 



