The 16th century saw the origins of the scientific revolution in Europe especially centred in the Rennaisance in Italy. Economically this was a response to the burgeoning trade in the Mediterranean between Italian ports and Middle Eastern and North African countries and under the tutelage of rich powerful families like the Medicis and also the transition from feudalism of the Middle Ages to the nascent capitalism in Europe. The geocentric theory of the earth was challenged by Galileo (Italian )and Copernicus (Polish) as a result of the intellectual foment brought in with capitalism. In mining, Georgius Agricola, who was trained as a physician began first-hand investigation of underground mines in the Erzgebirge Mts of Bohemia and wrote the treatise on this called De Re Metallica which was the authority on such mining/milling techniques for 200 years after. This was made possible by the personal investigation of the mines and discussion with the miners and mine managers which was a big break from the classical scholars who often merely speculated on things.