ANDREAS VESALIUS, ON THE FABRIC

OF THE HUMAN BODY, BOOK I, PAGE 4

...and teeth, and many of the bones of the fingers. In not a few bones, small holes foramina; small openings in the bone surface occur which are visible on the outside and on the surface: however, these do not penetrate the entire bone, but are instead prepared for the thicker veins and arteries that enter the bones. Openings of this kind occur here and there in the heel bone the calcaneus, the ankle bone the talus, the thicker parts of the holy bone the sacrum, and in the bodies of the large vertebrae. This is clearly because these parts are too thick to comfortably receive nourishment from vessels merely creeping over their surface.

By sensation.

A very slight difference depends on the sensation of the bones. For we believe that only the teeth are endowed with sensation, while the rest of the bones are destitute of it: although it is not wise to rashly strip all power of feeling from the bones, since in the frequent treatments we perform by hand surgical procedures, even the most excellent physicians assert that bones are sometimes affected by pain. Meanwhile, they are not ignorant of the fact that a certain membrane is wrapped around the bones, which the Greeks for that reason called the periosteon original: περιόστεον; literally "around the bone", as if you were to say "circum-ossal." It is because of this membrane that it has seemed to others that bones (if they feel anything at all) possess sensation.

Bones similar to a door and so on.? By concealment.

Furthermore, only the teeth are naked in the entire area where they protrude beyond the gums: meanwhile, the remaining bones are covered in every part and lie hidden before a dissection is made.

By the membrane surrounding the bones.

In addition to this, where the teeth protrude, they lack the common membrane that involves the bones the periosteum. This is also true of the interior surface of the skull where the brain is contained, which the tough membrane covering the brain the dura mater immediately lines. Otherwise, the previously mentioned membrane is wrapped around all other bones on every side, if you except those places where bones are either articulated with each other or otherwise constructed together.

WHAT CARTILAGE IS, AND WHAT IS ITS USE AND DIFFERENCE. Chapter II.

SINCE the present chapter is also common to all cartilages at once, we have placed no figures here by which they are delineated (because, of course, all of them would otherwise have to be included here), instead saving their images for the individual chapters in which they are privately described.

The nature of cartilage. Common use corresponding to the use of bones. a figure ch. 38 & fig. ch. 21 book 2. b figure ch. 35. c figure ch. 10 book 2. d 4th muscle table L. e 4th muscle table K. f 1st fig. 9th ch. Ξ, Ξ. g 1, 3 fig. ch. 19 A in B.

Decorative initial C featuring two cherubic children in a landscape; one child is seated on the left holding a human skull, while the other leans over on the right, seemingly examining bones or a skeleton laying on the ground.
CARTILAGE is softer than bone: yet it is an earthy part of the body, and the hardest particle after bone. It is entirely solid and filled with no small holes or cavities in the manner of bones, and is almost entirely devoid of marrow and sensation. Its use is quite varied. For first, it performs the same function as bones, since it is like a certain support fulcrum; a prop or point of stability to which neighboring parts may grow and be stabilized.ª For the cartilages of which the larynx the voice box consists elegantly perform the duty of bones, because certain muscles are implanted into them, and some arise from them. Furthermore, they shape the larynx just as we see the houses of peasants constructed from beams before the straw, tiles, and mud are applied to them. Indeed, you could not compare the bones and cartilages of men, stripped of flesh and then woven together, to any image more closely than to the frames of huts just recently erected and not yet adorned with branches or earth. By a similar reasoning, other cartilages take the place of bone where, with no bone located there, muscles attempt their insertion: which happens in the eyelids. For in the extremities of these,ᵇ oblong cartilages exist, into whichᶜ the muscles moving the eyelids are inserted. To these, the wings of the noseᵈ are formed by cartilages which, receiving the insertion of muscles just like bones, together withᵉ other cartilages born from the bones of the nose,ᶠ elegantly support and lift the tip of the nose in the manner of bones. Furthermore, the bones of the ribs end in cartilages,ᵍ corresponding to those bones in the duty of supporting: but from the abundance of cartilages taking the place of bones in this part, a peculiar use arises, on account of their softer...