[CHAPTER II]
Of the Heart.
How a Mans heart is placed in his Body.
That the Heart of Man is seated in the left side, is an asseveration, which strictly taken, is refutable by inspection, whereby it appears the base and centre thereof is in the midst of the chest; true it is, that the Mucro or Point thereof inclineth unto the left; for by this position it giveth way unto the ascension of the midriff, and by reason of the hollow vein could not commodiously deflect unto the right. From which diversion, nevertheless we cannot so properly say tis placed in the left, as that it consisteth in the middle, that is, where its centre resteth; for so do we usually say a Gnomon or Needle is in the middle of a Dial, although the extreams may respect the North or South, and approach the circumference thereof.
The ground of this mistake is a general observation from the pulse or motion of the Heart, which is more sensible on this side; but the reason hereof is not to be drawn from the situation of the Heart, but the site of the left ventricle wherein the vital Spirits are laboured; and also the great Artery that conveieth them out; both which are situated on the left. Upon this reason Epithems or cordial Applications are justly applied unto the left Breast; and the Wounds under the fifth Rib may be more suddenly destructive if made on the sinister side, and the Spear of the Souldier that peirced our Saviour, is not improperly described, when Painters direct it a little towards the left.
The other ground is more particular and upon inspection; for in dead Bodies especially lying upon the Spine, the Heart doth seem to incline unto the left. Which happeneth not from its proper site; but besides its sinistrous gravity, is drawn that way by the great Artery, which then subsideth and haleth the Heart unto it. And therefore strictly taken, the Heart is seated in the middle of the Chest; but after a careless and inconsiderate aspection, or according to the readiest sense of pulsation, we shall not quarrel, if any affirm it is seated toward the left. And in these considerations must Aristotle be salved, when he affirmeth the Heart of Man is placed in the left side, and thus in a popular acception may we receive the Periphrasis of Persius; ——Leva in parte mamillæ. when he taketh the part under the left Pap for the Heart; and if rightly apprehended, it concerneth not this controversie, when it is said in Ecclesiastes: The Heart of a wise Man is in the right side, but that of a Fool in the left, for thereby may be implied, that the Heart of a wise Man delighteth in the right way, or in the path of Vertue; that of a Fool in the left or road of Vice; according to the mystery of the Letter of Pythagoras, or that expression in Jonah, concerning sixscore thousand, that could not discern between their right hand and their left, or knew not good from evil.
That assertion also that Man proportionally hath the largest brain, I did I confess somewhat doubt; and conceived it might have failed in Birds, especially such as having little Bodies, have yet large Cranies, and seem to contain much Brain, as Snipes, Woodcocks, etc. But upon trial I find it very true. The Brains of a Man, Archangelus and Bauhinus observe, to weigh four pound, and sometime five and a half. If therefore a Man weigh one hundred and fourty pounds, and his Brain but five, his Weight is 27. times as much as his brain, deducting the weight of that five pound which is allowed for it. Now in a Snipe, which weighed four ounces two dragms, I find the Brains to weigh but half a dragm; so that the weight of the Body (allowing for the Brain) exceeded the weight of the Brain, sixty seven times and an half.
More controvertible it seemeth in the Brains of Sparrows, whose Cranies are rounder, and so of larger capacity: and most of all in the Heads of Birds, upon the first formation in the Egg, wherein the Head seems larger then all the Body, and the very Eyes almost as big as either. A Sparrow in the total we found to weigh seven dragms and four and twenty grans; whereof the Head a dragm, but the Brain not fifteen grains; which answereth not fully the proportion of the brain of Man. And therefore it is to be taken of the whole Head with the Brains, when Scaliger Histor. Animal. lib. 1. objecteth that the Head of a Man is the fifteenth part of his Body; that of a Sparrow, scarce the fifth.