Ideologies such as iatrophysics and iatrochemistry began to prevail. Samuel Hartlib was a patron and promoter of applied science, including alchemy and iatrochemistry. His medical practice appears to have been highly successful, which included iatrochemistry. He put his effort into the transmutation of metals and emphasized iatrochemistry in his works. Iatrochemistry also refers to the pharmaceutical applications of alchemy championed by Paracelsus. However, iatrochemistry was popular between 1525 and 1660, especially in the Low Countries.