Johann Joachim Becher

Johann Joachim Becher (1635 to 1682) was a German physician, alchemist and polymath of the seventeenth century, best known for the terra pinguis theory that later grew into the phlogiston theory of combustion. Born in Speyer during the Thirty Years War, he lost his father young and supported his family through handicrafts and teaching while studying on his own. In 1654 he published a discourse on the universal medicine of the philosophers' stone under a pseudonym, and in 1657 he became professor of medicine at the University of Mainz and physician to the archbishop-elector. He later served as physician to the elector of Bavaria and as a commercial councillor in Vienna, where he promoted manufacturing and trade and became the most original theorist of Austrian cameralism. His Physica subterranea of 1669 was regarded by William Cullen as the most considerable of his writings. He travelled in the Netherlands, Scotland and Cornwall, and died in London in October 1682.