For thousands of years, the hydraulic know-how of the East was no more than an oral tradition. But with the conquests of Alexander the Great, this oral tradition comes into contact with the Greek spirit of observation and analysis. The city of Alexandria, at the maritime front door of Egypt, for several centuries serves as the scientific center of the known world. The understanding and know-how of the scientists of the Alexandrian school remain unequalled during the following millenium, both in the East and the West, until the advent of the Renaissance.
Roman engineers, the inheritors of Etruscan and eastern techniques, influenced by the Greeks and endowed with a strong practical sense, leave the influence of their hydraulic achievements around the entire Mediterranean perimeter.
The fall of the Roman Empire ushers in the intellectual decadence of the West, but the East continues to develop up until the Mongol invasions of the 12th century AD. Then the East, in its turn, enters a period of profound reversal.
In China, whose hydraulic development began later, technical developments transcend the millennia up through modern times. The scale of these developments reflect the vast expanse of the country itself. From the 1st century BC through the 15th century AD, China serves as mankind’s principal nursery of technical innovations.
Meanwhile, during the Middle Ages the West even forgets that the earth is round. Nevertheless during the West’s demographic expansion of the 12th and 13th centuries, hydraulic development blossoms as lands are drained and mills are constructed.
