What roman author described the technique of Opus quadratum?
Opus quadratum Opus quadratum is an ancient Roman construction technique, in which squared blocks of stone of the same height were set in parallel courses, most often without the use of mortar. The Latin author Vitruvius describes the technique.
Polybius Polybius ( ; Greek: Πολύβιος , "Polýbios"; c. 200  – c. 118  BC) was a Greek historian of the Hellenistic period noted for his work, "The Histories", which covered the period of 264–146 BC in detail. The work describes the rise of the Roman Republic to the status of dominance in the ancient Mediterranean world and included his eyewitness account of the Sack of Carthage in 146 BC. Polybius is important for his analysis of the mixed constitution or the separation of powers in government, which was influential on Montesquieu's "The Spirit of the Laws" and the framers of the United States Constitution.