Geometric Working Drawing of a Gothic Tierceron Vault in Seville Cathedral.

Some of the pavements in Seville Cathedral still display full-scale geometric working drawings (known as monteas in Spanish) of architectural elements, such as flying buttresses, arches and windows. We have recently discovered a new one, which was completed in the final stage of the Gothic work between 1490 and 1506. The documentation, coupled with the mapping and geometric analysis of the drawing found and its comparison with the examples reproduced in architectural manuscripts and printed books, confirms that it corresponds to the construction of a vault with diagonal ribs and tiercerons. Our aim here is to present, document and decipher the keys to a rare example of a geometric drawing for this type of vault, which may in turn furnish interesting data about geometric systems for controlling form and how they were used in stone construction processes at a fascinating time in the transition from Gothic to Renaissance architecture. This article forms part of the research currently being conducted under the auspices of projects HAR2012-34571 sponsored by Institute of Architecture and Building Science and Spain's Ministry of Economy and Competitiveness, in which the authors are involved, and within the framework of the Late Gothic Network. [ABSTRACT FROM AUTHOR]