 His sawmill "Het Juffertje" soon developed into a more advanced version, a type known today as the "paltrokmolen" (post mill), which played a key part in the economic success of the Dutch Republic during the Dutch Golden Age in the 17th century by enabling the mass construction of ships for overseas trade.The mill turned the Zaan district, north of Amsterdam, into the world's first industrial area.In addition to inventing the sawmill, Cornelis Corneliszoon van Uitgeest also held various other mill-related patents, including an early version of a centrifugal pump.