Engraving of a mechanism invented by Emanuel Swedenborg's (1688-1772) teacher, the Swedish inventor and engineer Christopher Polhem (1661-1751). It was one of a number of new machines Polhelm installed at the Falun Mine in 1707. The lifting mechanism was powered by two cranks, one at either side of the wheel stock, instead of one. Illustration from Swedenborg's 'Regnum Subterraneum sive Minerale de Cupro et Orichalco' (The Subterranean or Mineral Kingdom in respect to Copper and Bras), published in Dresden in 1734. This book formed part of his 'Opera philosophica et mineralia' (Philosophical and Logical Works), which dealt with the creation of the world, and drew on his interpretations of metallurgy and metaphysics.
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