Out of Scope: Unexpected Titles in the Rare Book Collections

Michele Mercati (1541-1593) was a physician, botanist, and geologist, as well as the superintendent of the Vatican Botanical Garden. He revived Lucretius’s Three-Age system after recognizing that what had been referred to as naturally- or mythologically-occurring “thunderstones” were actually stone weapons and tools, thus realizing there was a period in which metallurgy was unknown. Mercati was also the superintendent of the Vatican Botanical Garden and sought to make the papal metal collection a center of study on the earth and its minerals.

Metallotheca served as a catalogue for the papal collection of fossils and minerals that were collected under Pope Sixtus V, as shown in this copper engraving. The image reflects the breadth of subjects covered by Metallotheca (natural history, mineralogy, paleontology, medicine, and botany) as well as the contemporary interest in taxonomy and classifying objects into collections.