Men and methods
Earth science was not taught in schools in the seventeenth century. Geology began in principle with Steno’s Prodromus of 1669, which reflected tendencies in the European curiosity about nature, but had little contemporary impact. As a child in busy Protestant Hamburg, Otto Sperling was influenced by Renaissance ideas in the early 1600s and investigated plants with his family’s encouragement; he continued in pharmacy and later in medicine in Leiden. As a student he visited the relatively strong medicine milieu in Copenhagen and had the opportunity to sail as a participant in King Christian IV’s official visit to Bergen. Venturing into southern Norway’s mountainous landscapes, he studied plants, animals and rocks. Sperling’s nature studies continued on journeys in northern and southern Europe and he graduated as Doctor medicinae in Padova in 1627. En route towards England, his ship was driven to Norway, where the locals persuaded him to settle as a physician. An encounter with the Danish nobleman Corfitz Ulfeldt (1606–64) took Sperling to some of the highest medical posts and later, during Denmark–Norway’s decline, dragged him into the political maelstrom. Sperling’s autobiography, written in his late sixties in a Copenhagen prison, is testimony to the importance of Earth science to Sperling’s philosophy and performance as a doctor.