An unusual silver celestial planisphere in the Whipple Museum

An unusual silver celestial planisphere is held in the collection of the Whipple Museum of the History of Science (Wh.1762); little information about this object is recorded in the museum’s documentation. A comparison of this silver example with celestial planispheres printed on paper, coupled with the consideration of other aspects of the lives and work of the cartographers and instrument-makers involved in producing such objects, suggests some possibilities regarding its production. Through this individual case study, I aim to demonstrate that the careful examination of an individual instrument, coupled with an understanding of the class of instruments to which it belongs and the milieu in which it was produced, can result in a deeper understanding of any given artefact, its circumstances of design and manufacture, and its intended use and users.