Block Mill The Block Mills have entered service at Portsmouth dockyard. This is a decisive step for the introduction of steam engines into shipyards. Two centuries after the introduction of wind-powered sawmills into Zaandam works, we are attending the advent of a new era of mechanisation in shipbuilding. ¤ Cornelis Corneliszoon van Uitgeest is the inventor of the wind-powered sawmill, which swiftly developed during the first half of the 17th century in the United Province