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[[left justified]] 145) [[/left justified]]
is in its systole, or state of contraction.  This is apparent to those who in what a retrograde manner they arise, making very acute angles with that part of the [[underline]] aorta [[/underline]] which is nearest the ventricle.

     Besides, the muscular [[strikethrough]] ventricle [[/strikethrough]] substance of the heart, to which these two arteries are distributed, is during its systole in so firm and contracted a state as is very unfavourable to the passage of the blood through it at this juncture.  These are the causes that hinders the blood's entering these coronary arteries, at the same time [[insert]] in which [[/insert]] it enters the rest, all over the body.

     That the blood when forced out of the left ventricle into the [[underline]] aorta [[/underline]], or great artery, makes immediately, on the cessation of the impelling power, a considerable push back again, may be reasonably inferred from the known use of the semi-lunar, and several other valves belonging to the heart; and from the resistance, the sides of the arteries, and the blood with which they are replete, must necessarily make to its progressive motion.

     Now if the impetus with which it recoils on the valves be sufficient to raise them, surely it must enter the coronary arteries at this time, especially as the soft relaxed state of the heart, as well as the direction of the arteries themselves, so remarkably favour such a transit; and that this is the very case any one may satisfy himself by Autopsy, on viewing a frog opened, or other small animals, when he will behold the heart become red at the beginning of each dyastole, or opening thereof, and to continue so during the whole time of its relaxed or inactive state, till the commencement of the systole, when it immediately becomes white, and continues so during the whole contraction.  What greater demonstration can be required than what these two remarkable circumstances afford, both that the blood does enter these two coronary arteries during the hearts dyastole, and does not in the least during its systole, when it enters the [[underline]] aorta [[/underline]], and other arteries.

     In what manner this particular contrivance of supplying the heart with its blood during the dyastole was designed to influence each succeeding systole, and other secrets belonging to the same, the great [[Kapolo?vwshs?]] only knows.

[[in Left Margin]]Case of a lad, who fractured his skull.  Gents. Mag. May. 1768. p. 227, by J. Cooke, of [[underline]] Leigh [[/underline]].  Also in the Universal Museum, Vol. III. p. 247. for 1768.[[in Left Margin]]

A Lad, by a fall, fractured his skull, and was trepanned.  What was very surprising, the wounded side enjoyed all its functions freely, while the contrary side, unhurt, directly lost its power of motion, and became paralytick by the blow.  His fingers, on the opposite side, continue contracted still, as also his ham [[?]], otherwise as to health and senses, he is as well as ever, although he has lost half his brains.

It is plain, that it proceeded from the different origin of the nerves from the opposite side in which they terminate. For which end they cross before they make their exit through the
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