of the latter, conveying to man the different faculties with which he may be endowed.
From the left ventricle of the heart, alongside its auricle, two arteries are given off. One of them, which is only furnished with one tunic (as in the case of a vein) and which is called the arteria venalis (pulmonary vein), carries to the lungs the blood which they require for their nourishment, and breaks up into many branches after entering these structures; the other artery is provided with two tunics and is called the grand artery (the aorta). From the latter vessel are given off the numberless arteries which are distributed throughout the entire body—vessels which transport to every organ and structure both the blood which they need for their nourishment and the spirit required for their revivification. When this spirit passes into the ventricles of the brain it is subjected to a new species of digestion, which converts it into the spirit of the soul. Similarly, when it enters the liver it becomes a nutritive spirit; when it enters the testicles, a generative spirit, and so on through all the different organs.
