FIbres are called in Greek 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, in Latine villi, although that name is sometimes communicated both to Nerues and to Tendons: some call them 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, because they are like the strings or lines in plants, or graynes in the woode. Laurentius defineth them to be Similar partes colde and dry ingendered of the Seede, and therefore * 1.1 white, solid and long like fine spun threds, destinated or appoynted for motion, and to hold the flesh of the parts, wherein they are, together.
The first particles of the definition are so manifest as they need no explication, the latter which designe their vse or finall cause wee will open in a fewe wordes.
There are two especall vses of Fibres, Motion and Preseruation of flesh. Motion ac∣cording to the Physitians is threefold, Animall, Vitall and Naturall. * 1.2
Animall or Voluntary Motion is performed by the helpe of the muscles: a Muscle is * 1.3 moued when his fibres are either intended or drawne toward their originall, and there∣fore sayeth Galen in the 8. de Anatom. administrat. if you cut all the fibres ouerthwart, the muscles would presently loose all their motion.
The Vitall motion belongeth to the Heart and to the Arteries, for the heart hath his fibres manifold and very strong by whose helpe he is distended, contracted and quieteth himselfe. The Arteries also haue their fibres, in their inner coate many transuerse; in the vtter coate oblique and right.
That Motion we called Naturall is most manifest in Attraction, Retention and Ex∣pulsion. Wherefore all manner of Motions proceede from fibres, but their common ac∣tion is Contraction.
Notwithstanding we must know that these naturall Organs had not their fibres allo∣wed * 1.4 them for a peculiar Traction, Retention and Expulsion, but for a common and offi∣ciall. So the Stomach, the Guts, the Veines, the Arteries, the VVomb, the Bladder, the Heart and such like, did not stand in neede of fibres for their priuate nourishment (for the bones and the brayne, and the gristles and the flesh of the bowels doe draw their proper Aliment without fibres) but for a common and officiall action. The heart for the ge∣neration of vitall spirits; the Arteries for the commoderation or tempering of the natiue heate; the Veines for the transmission or transportation of bloud; the Stomacke for the making of the Chylus; the Guts for the distribution of the same Chilus, and the excretion or euacuation of excrements; the Bladder for miction or making of water; the VVombe for Conception and for the Birth.
The other vse of the Fibres is the custody or preseruation of the Flesh, as wel muscu∣lous * 1.5 as that which maketh the proper substance of the part, for the fibres are as it were the first stamina or the warpe, whose empty distances the flesh like the woofe filleth vppe. There are also other peculiar vses of Fibres in the Veines and Arteries, to wit, that therby they might be better extended after all the violent motions of the bloud, and so become lesse subiect to mischiefe.