(Chapter 1) Footnote 3:

Cf. Galen, De anatomicis administrationibus 1.2.218: “As poles to tents and walls to houses, so are bones to living creatures, for other features naturally take form from them and change with them.” (tr. Singer 1956). The architectural metaphor, used (among other places) by Cicero in De natura deorum 2.140-141, was one of particular significance for Vesalius’ idea of the human body; see note 29 in chapter 16 on his conception of the vertebrae as a keystone arch. Vesalius makes a similar architectural statement in the first chapter of Book II, where the muscles and ligaments are described as “foundations and bases” of other bodily parts.