The north and south wings of the cloister bear thirteen single capitals between the massive corner piers. In the west wing four paired capitals extend in a similar manner between the corner pillars and a centrally placed pier alternating with two single capitals, while the east wing is currently adorned with three capitals decorated with vegetal motifs; although these were not carved at the same time as the other cloister capitals. Since 1887 the original capitals have been conserved in the Museo Civico d’Arte Antica in Turin. In 1997 one of the double captals from the west wing of the cloister was destroyed by vandalism and has now been replaced with a copy. The capitals are carved from white marble but were, however, already covered with a black coating in the second quarter of the 17th century – which has prevented the damage naturally caused from dampness seeping into the stone. As a result, except for some fractures, the capitals have been relatively well preserved along with their many inscriptions.
The majority of the capitals of Sant’Orso are either decorated with figures or narrative scenes. The historiated capitals can be assigned, except for a few exceptions, to a corinthian capital type. The abacus is formed by a centrally aligned protruding and stylized abacus flower, while the capital itself swells out in a convex manner at the corners in a similar manner so that its form resembles the shape resembles a scalloped capital. The figures and scenes adapt themselves to the shape of the calathos and therefore are set in front of it. The narrative scenes are distributed irregularly on the calathos so that the narrative style is continuous and composed primarily of single scenes. The single figure exhibits a more representative character so that it behaves, for the most part, as an isolated central figure not immediately interacting with others in the narrative.
The base of the figures always projects from
the astragal of the capital, which is deeply incised, in order to furnish sufficient spatial depth. The calathos remains hidden behind the figures or leaves and is only occasionally visible in the lower part of the capital and it merges with the floral decoration of the capital and the abacus.
The five capitals with the representations of the prophets on the south side of the cloister also follow this principle and create, moreover, a homogeneous unity in which they follow a formal procedure of representation with regard to content. On all four capital sides the busts of the prophets are placed in front of the calathos, as clipei, with scrolls in hand.
The historiated capitals thematise both Old Testament stories (Abraham, Daniel, Nebuchadnesser, Job, Jacob), as well as New Testament ones (Christ’s infancy, Lazarus), as well as hagiographic representations such as the life and miracles of Saint Ursus, the patron and founder of the Abbey.
With the typical variety for a cloister of this period and the proximity of narrative, figurative, and ornamental capital decoration, several motifs – for example, in the Prophet capitals – repeat themselves over and over in the details and, therefore, they distinctly determine the overall image of the cloister
itself. The holes drilled to create a decorative pattern in the representation of textiles - such as in the curtain in capital N3B4 (the Nativity) and capital W1EB16 (the Birth of Jacob and Essau) or the blanket in capital N5B6 (Joseph’s Dream), for example, appear almost stereotyped. Also, the use of one and the same figural type for the Three Wise Men on capital N4B5, who all hold their gifts with the same gesture, while bending their left leg, show little artistic variability of movement in the figural motifs.