Mårten Triewald

Triewald's mercantile activities took him to London where he attended lectures in Newtonian Experimental Philosophy given by John Theophilus Desaguliers and with whom he later corresponded.

In 1716 Triewald was employed as an inspector at a coal mine in Newcastle, where he studied mechanics and the steam engines used there, and made improvements to them.

He returned to Sweden in 1726 and at Dannemora mine and built a steam engine there under the designation "fire and air machine" (eld- och luftmachin in archaic Swedish).

In 1728 and 1729 Triewald held lectures in mechanics at the Swedish House of Nobility, and demonstrated a collection of physical instruments that he had bought in England.

Triewald was given the title director mechanicus, and in 1735 was appointed kapten-mekanikus (Captain of Mechanics) at the Fortification Administration, deemed to be "the only one in the country suitable for this post", and given an annual pension by the Parliament.