Carthage is defeated in 202 BC, at the end of the Punic wars. This leaves Rome without a rival in the western Mediterranean, so she immediately begins her expansion toward Greece and the Orient. This evolution is inexorable, despite some temporary setbacks due to resistance such as that of the king of the Pontus, Mithridate Eupator (in whose land the remains of one of the first water mills has been found, as noted in the preceding chapter). The annexation of Egypt by Augustus in 31 BC effectively ends the Roman expansion toward Asia. After the occupation of the coast of North Africa at the end of the 1st century AD, the Mediterranean becomes the mare nostrum, a sea that is entirely bordered by Roman lands.
One can clearly see the appearance of the Alexandrian heritage in Roman techniques during the Augustin period. The monumental work On Architecture of Marcus Vitruvius Pollio, who lived in the 1st century BC under Julius Caesar and Augustus, paints a vast tableau of techniques for the information of the new emperor. This broad-brush panorama integrates the skills of the Alexandrian School from the 3rd century BC. It describes the siphon, whose use, when implemented with Roman know-how, had already made it possible for water from the Aqua Marcia aqueduct to reach Capitol and Palatain (in 144 BC). It also describes use of the Ctesibios pump, lifting water wheels, etc. During the four centuries of prosperity of the Empire — until its economic decline of the 3rd century AD and the fall of the western Roman Empire in 410 AD — indelible symbols of the power of Rome were left in the development of water supply, water use in the cities, agricultural productivity in the provinces, and the development of maritime commerce. Many of the countless hydraulic structures and installations that were constructed remain with us today as symbols of that power.
