The Romans were undoubtedly master engineers. They were experts at civil engineering, building roads, improving sanitation, inventing Roman concrete, and constructing aqueducts that adhere to tolerances impressive even by today’s standards. Perhaps the best evidence of their aptitude is the fact that many of those structures still stand today, almost 2000 years later. They even began dabbling in technology vastly ahead of their time. Hero of Alexandria drew up plans for a rudimentary steam engine in his Spiritalia seu Pneumatica. He called it the aeolipile.