To an approximate scale of 1:15

• c.1513/14
  Datable to c.1513/14

Pen and brown ink over black chalk, overlaid with traces of a purple-brown, oil-based substance

Bernardo della Volpaia

The keystone, which takes the form of a scroll with a recessed front and elaborately decorated volutes at the sides (one shown) is not identified by an annotation but it is unquestionably the one above the central archway of the Arch of Septimius Severus (cf. Desgodetz 1682, p. 213), even though the figure of Mars on the front face is omitted. The identification is corroborated by the depicted profile of the adjacent archivolt, which likewise accords with that of the central archway. For the keystone itself, the combination of a profile with an oblique view broadly aligns with the hybrid format frequently seen elsewhere in the codex, and it allows the keystone’s face to be shown, and its position understood in relation to that of the archivolt. As is also customary in the codex, much of the decorative detail, including the acanthus leaves below the bottom of the keystone as well as the figure of Mars on its front, is excluded. The keystone had attracted attention previously, being depicted in the Codex Barberini and the Codex Escurialensis, which both show it in profile, as does a later depiction included in an early copy drawing by Andrea Palladio who, like in the Coner depiction, omitted the figure. The Coner drawing was copied, albeit in simplified form, by Michelangelo.

A line drawn near the back of the keystone in an oily medium, presumably to correct the awkward perspective, is a later addition in a different hand. An offset of this line, visible on the verso of Fol. 89/Ashby 148, suggests that it was added before the codex was dismantled and transformed into an album in the seventeenth century.

RELATED IMAGES: [Michelangelo] Florence, CB, 1Ar: left side (De Tolnay 1975–80, 4, p. 49; Agosti–Farinella 1987, pp. 92–93)

OTHER IMAGES MENTIONED: [Giuliano da Sangallo] Rome, BAV, Barb. lat. 4424 (Codex Barberini), fol. 9r (Hülsen 1910, p. 17; Borsi 1985, pp. 404–09); [Anon.] El Escorial, Real Monasterio, 28-II-12 (Codex Escurialensis), fol. 25v (Egger 1906, pp. 88–89); [Andrea Palladio] Vicenza, Museo Civico, D 13 r (Zorzi 1959, p. 56; Puppi 1989, p. 105)

OTHER DRAWINGS IN CODEX CONER OF SAME SUBJECT: Fol. 34r/Ashby 54; Fol. 56r/Ashby 95; Fol. 64v/Ashby 110

Ashby 1904, p. 71
Census, ID 47388

Drawing

Digitisation of the Codex Coner has been made possible through the generosity of the Census of Antique Works of Art and Architecture Known in the Renaissance, Berlin.

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