Alberti and Military Architecture in Transition

Alberti’s contribution to the nascent science of fortifications in the 1450s is often ignored, but a careful reading of his descriptions of fortifications show that he was the first to describe the elements of fortification formally in the precise mathematical terms of shape, measurements, relationships, proportions. In forming his ideas, Alberti embraced both the old and the new. The old he re-elaborated and set in modern terms, and although he cites numerous ancient authors as sources for his information about fortifications, the obvious historical source for Alberti’s description of the elements of fortification is Vitruvius. On the other hand, Vitruvius alone cannot account for all of Alberti’s knowledge of military architecture. Plans with well-define geometric shapes, solid walls, scarped bases, curtains, towers open to the interior appropriated located on the bases of flanks, loopholes for grazing fire conjoined to systems of defense for dropping stones and other missiles vertically, structures in earth: all of these show that Alberti was in possession of a thorough knowledge of the state of fortifications in his day. All of these features are present in fortresses that had been built some years earlier based on designs attributed to Filippo Brunelleschi. We examine the fortress at Vicopisano to show a built example that Alberti may have seen and drawn on.