The late Middle Ages saw a technological revolution consisting in applying water energy instead of human labour to power machines. One of its most conspicuous results was the common use of watermills, connected with the process of settlement. In the Teutonic Order state the construction and use of watermills was regulated by paragraph 13 of the Chelmno charter. In practice, the erection of mills was a prerogative of the Teutonic Order, which gave individual licenses to build mills and later collected rent from their operation. This arrangement allowed the Teutonic Knights to control the efficient use of rivers as a source of water power. The work of a watermill depended on a pile-up up water. To protect the interest of particular mills it was determined precisely at what distance new weirs could be built; sometimes general bans on the construction of new mills were issued. It was also specified how many wheels a new mill was allowed to have and whether it could later be extended. In order to increase the output of a mill it was necessary to supply it with more energy. This required a higher weir. Milling licenses tried to prevent the arbitrary raising of water level by millers, establishing the maximum allowed level. Another way to supply a mill with more water, and consequently energy, was to build an extra pond, called the 'upper pond', which was a reserve of energy to be used if needed. In the Teutonic Order state there were many watermills concentrated on several rivers, which were thus exploited very intensively. The best known example is a complex of mills on the Mlynówka Malborska, built, used and gradually extended by the Teutonic Order. Apart from watermills waterpower was extensively used in boat mills.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.