Herbert Dennert †:
Gottfried Wilhelm Leibniz and mining in the Upper Harz Mountains
When the universal thinker and scholar, Gottfried Wilhelm Leibniz, came to the court of the Guelfs in Hanover in 1676, silver mining in the Upper Harz Mountains was among the leading mining areas in Europe. Silver mining represented the most important source of money for the Guelf dukes in Hanover and Wolfenbüttel. Leibniz was therefore almost inevitably confronted with mining in the Harz Mountains, especially because of the system of ponds for collecting the water for propelling the water-wheels to lift water, which was necessary because of the geological morphology, was almost exhausted and new ways for making further energy available had to be found.
Leibniz's idea was to recycle the propulsion water via reservoirs with the aid of wind energy. In the court's contract with Leibniz we read, "by means of the conjunction of wind and water to keep the ditches a marsh". Leibniz failed with this idea as well as further ideas for improving shaft conveyance and thus for improving the use of energy -- balance rope, winches and conical drums for equalizing moments which, however, today are all accepted, state-of-the-art techniques.
Whereas recent works on Leibniz's influence on mining in the Harz Mountains have all found their point of access via research into Leibniz himself, a hitherto unpublished manuscript recently discovered in the literary estate of the retired Senior Mining Counsellor, Herbert Dennert, shows up a new facet.