ABSTRACT
The construction of Gothic is a popular subject. However, little has been written about the actual erection of cross vaults. Very few original sources have survived. Among them the Treatise of Rodrigo Gil de Hontañón, written ca. 1550, contains the only detailed description of the erection of a late-Gothic star vault. Rodrigo Gil gives also rules for the sizing of the vault elements: the thickness of the ribs and the weight of the bosses. The paper analyzes the procedure, remarks its rationality and discusses the validity of the design rules. In particular the stability of the stone skeleton during construction is studied.
