and the gastraphetes crossbow in warfare, hollow bronze-casting in metallurgy, the dioptra for surveying, in infrastructure the lighthouse, central heating, a tunnel excavated from both ends by scientific calculations, and the ship trackway. In transport, great progress resulted from the invention of the winch and the odometer. Further newly created techniques and items were spiral staircases, the chain drive, sliding calipers and showers. Roman Empire The Roman Empire expanded from Italia across the entire Mediterranean region between the 1st century BC and 1st century AD. Its most advanced and economically productive provinces outside of Italia were the Eastern Roman provinces in the Balkans, Asia Minor, Egypt, and the Levant, with Roman Egypt in particular being the wealthiest Roman province outside of Italia. The Roman Empire developed an intensive and sophisticated agriculture, expanded upon existing iron working technology, created laws providing for individual ownership, advanced stone masonry technology, advanced road-building (exceeded only in the 19th century), military engineering, civil engineering, spinning and weaving and several different machines like the Gallic reaper that helped to increase productivity in many sectors of the Roman economy. Roman engineers were the first to build monumental arches, amphitheatres, aqueducts, public baths, true arch bridges, harbours, reservoirs and dams, vaults and domes on a very large scale across their Empire. Notable Roman inventions include the book (Codex), glass blowing and concrete. Because Rome was located on a volcanic peninsula, with sand which contained suitable crystalline grains, the concrete which the Romans formulated was especially durable. Some of their buildings have lasted 2000 years, to the present day. In Roman Egypt, the inventor Hero of Alexandria was the first to experiment with a wind-powered mechanical device (see Heron's windwheel) and even created the earliest steam-powered device (the aeolipile), opening up new possibilities in harnessing natural forces. He also devised a vending machine. However, his inventions were primarily toys, rather than practical machines. Inca, Maya, and Aztec The engineering skills of the Inca and Maya were great, even by today's standards. An example of this exceptional engineering is the use of pieces weighing upwards of one ton in their stonework placed together so that not even a blade can fit into the cracks. Inca villages used irrigation canals and drainage systems, making agriculture very efficient. While some claim that the Incas were the first inventors of hydroponics, their agricultural technology was still soil based, if advanced. Though the Maya