The Geometric Enigma of Small Baths at Hadrian's Villa: Mixtilinear Plan Design and Complex Roofing Conception

摘要

Starting in the late Domitian age, through Nero's Empire and ending in Hadrian's principate, an increasing technological shift relating to both opus caementicium and centring work made it possible to build cupolas with unprecedented technical solutions in terms of both dimension and shape. Hadrian's strain was applied to the development of innovative domes, as shown in various pavilions in his Tiburtine Villa and perfectly expressed by the well-known episode reported by Cassius Dio concerning the criticism expressed by Apollodorus of Damascus on the Emperor's ribbed vault design. Many researchers agree on the importance of the octagonal hall of the Villa's Small Baths in terms of its unusual shape and daring structure and on the significance of the access vestibule of the Piazza d'Oro. The geometry and construction knowledge suggested by their shapes make them perfect examples of the importance of mathematicians' influence on architects during the design process.