Le absidi delle chiese Madri di Assoro e Pietraperzia (XV-XVI secolo)

This contribution focuses on two case studies dating from the 15th and 16th centuries: the apse of the mother church of Assoro and the mother church of Pietrap- erzia, both in the province of Enna, for which it is pos- sible to identify common constructive characteristics and a close relationship including in terms of the clients involved. The study examines historical aspects and those of a geometric and construction nature, taking also into ac- count the lasting influence of the apse. The investigation, hampered by the limited archival sources, both literary and iconographical, is based on the study of the few documentary records found, as well on the direct survey and examination of the two apses, offering a comparison between the two solu- tions and with other models similar to them with re- gard to the geometric characteristics of the building and roofing and to the building techniques and decora- tive motifs used. The first case is represented by the apse of the Church of San Leo in Assoro, a building that was recently ren- ovated, dating from the end of the 15th century and commissioned by the noble family of the Valguarneras, related with the Barresis of Pietraperzia. The apse is marked by a polygonal plan with octagonal matrix, flanked by two almost square chapels, covered by groin vaults. Of particular interest is the vault covering the apse, consisting of a ribbed umbrella-type vault, with radial arches in freestone culminating in a key- stone, whose type can be found in other contempo- rary edifices. The other case is represented by the mother church of Pietraperzia, reconfigured on a preexisting medieval edifice by the Barresi family at the beginning of the 16th century and subject to subsequent works. In particular, the documentation found made it possible to date the apsidal structure to a period between the 1510s and the early half of the 16th century. In this case as well, as in Assoro, the apse has a polyg- onal pattern with octagonal matrix whose geometry is clearly visible externally, consisting of a rectangular space on which a portion of an octagon emerging from the perimeter wall is grafted. At the tips of the polygon are two sturdy square stone buttresses, which have en- sured stability over the centuries. The apsidal structure is the only surviving part of the building dating back to the 16th century, radically altered by changes imple- mented since 1791, when the church was reconfigured according to a strictly classicist style. Direct examination and surveys of the apsidal struc- ture, together with an analysis of its extant elements and the study of the few literary, documentary and iconographic sources found, has allowed us to make some considerations concerning the possible original configuration of the church, offering a virtual recon- struction as well. The church was built according to a scheme with nave and two aisles, with the nave slightly taller than the aisles, allowing the opening of a row of windows posi- tioned along the same axis as the arches of the nave, and a transept not taller than the perimeter wall. The covering was probably a roof, while the apse area prob- 321 322 ably had a ribbed vault, whose radial arches were set on four connecting corbels, still visible in the interior of the apse (now used as a sacristy). One last consideration regards the comparison be- tween the two examples studied and other apses with a similar polygonal plan with octagonal matrix covered with ribbed vaults. The other examples include the apse of the 16th-century churches of Santa Maria della Catena, Santa Maria dello Spasimo and San Marco, in addition to the Church of San Domenico in its late 15th- century configuration, all located in Palermo.