1 Scientia in Republican Era Stone and Concrete Masonry Marie D. Jackson Department of Civil and Environmental Engineering, University of California, Berkeley, CA, 94111 Cynthia K. Kosso Department of History, Northern Arizona University, Flagstaff, AZ, 86011 A Companion to the Archaeology of the Roman Republic, First Edition. Edited by Jane DeRose Evans. © 2013 Blackwell Publishing Ltd. Published 2013 by Blackwell Publishing Ltd. 1 Republican Era Construction Engineering Monumental buildings constructed in Rome during the nearly 500 years of the republican era record a progressive evolution in builders’ refinements of diverse construction methods with local volcanic building materials, and their innovations in developing the complex stone and concrete masonry of the first century BCE. Descriptions of extant examples of these masonry elements integrated with analyses of Vitruvius’ de Architectura, written ca. 30 – 20 BCE, reveal that these builders were astute engineers. They recognized the material characteristics of the volcanic and sedimentary deposits of the Roman landscape (Figure 1) and selected specific rocks to enhance the structural stability and long-term durability of monumental architecture in Rome (Frank (1924); Blake (1947); Lugli (1957); DeLaine (1995); Jackson and Marra (2006); Jackson et al. (2005); (2006); (2007); (2010a); (2011)). The central objective of this chapter is to investigate the hypothesis that republican era builders integrated a long standing tradition of thoughtful reasoning and invention with skilled workmanship to develop highly sustainable masonry materials, construction technologies, and engineering solutions (de Architectura 2.1.2, 1.1.1). Indeed, Vitruvius writes that the plan, elevation, and perspective of architectural design: