Arteries.] Arteries are long and hollow, with a double skin to convey the vital spirit; to discern which the better, they say that Vesalius the anatomist was wont to cut up men alive. [958]They arise in the left side of the heart, and are principally two, from which the rest are derived, aorta and venosa:  aorta is the root of all the other, which serve the whole body; the other goes to the lungs, to fetch air to refrigerate the heart.

Veins.] Veins are hollow and round, like pipes, arising from the liver, carrying blood and natural spirits; they feed all the parts.  Of these there be two chief, Vena porta and Vena cava, from which the rest are corrivated.  That Vena porta is a vein coming from the concave of the liver, and receiving those mesaraical veins, by whom he takes the chylus from the stomach and guts, and conveys it to the liver.  The other derives blood from the liver to nourish all the other dispersed members.  The branches of that Vena porta are the mesaraical and haemorrhoids.  The branches of the cava are inward or outward.  Inward, seminal or emulgent.  Outward, in the head, arms, feet, &c., and have several names.

Fibrae, Fat, Flesh.] Fibrae are strings, white and solid, dispersed through the whole member, and right, oblique, transverse, all which have their several uses.  Fat is a similar part, moist, without blood, composed of the most thick and unctuous matter of the blood.  The [959]skin covers the rest, and hath cuticulum, or a little skin tinder it.  Flesh is soft and ruddy, composed of the congealing of blood, &c.

SUBSECT.  IV.—­Dissimilar Parts.

Dissimilar parts are those which we call organical, or instrumental, and they be inward or outward.  The chiefest outward parts are situate forward or backward:—­forward, the crown and foretop of the head, skull, face, forehead, temples, chin, eyes, ears, nose, &c., neck, breast, chest, upper and lower part of the belly, hypocondries, navel, groin, flank, &c.; backward, the hinder part of the head, back, shoulders, sides, loins, hipbones, os sacrum, buttocks, &c.  Or joints, arms, hands, feet, legs, thighs, knees, &c.  Or common to both, which, because they are obvious and well known, I have carelessly repeated, eaque praecipua et grandiora tantum; quod reliquum ex libris de anima qui volet, accipiat.

Inward organical parts, which cannot be seen, are divers in number, and have several names, functions, and divisions; but that of [960]Laurentius is most notable, into noble or ignoble parts.  Of the noble there be three principal parts, to which all the rest belong, and whom they serve—­brain, heart, liver; according to whose site, three regions, or a threefold division, is made of the whole body.  As first of the head, in which the animal organs are contained, and brain itself, which by his nerves give sense and motion to the rest, and is, as it were, a