Using globes and celestial planispheres in restoration England.

Abstract

Globes and celestial planispheres were not merely static instruments that were used to display knowledge about the Ea1ih and the heavens, but were very much instruments of calculation to be manipulated by the user. I show that this is the case in Restoration England, through a consideration of instruments produced at the time alongside the texts on their use, also providing an insight into the individuals who participated in the cartographic enterprise at many different levels. A brief account of the history of celestial cartography, English instrument-making, and the practice of natural philosophy, mathematics and astronomy in Restoration England introduces the context within which the globes and celestial planispheres I am interested in were produced. The form and uses of a globe are described (using a seventeenth century text as a basis) in order to acquaint the reader with the relevant terminology, as well as illustrating the wide range of questions resolvable using the globes and the relative facility of doing so. The earliest extant English printed globes and celestial planispheres are examined, as these were not only important in their own right, but also inspired the makers in the Restoration period. Further background on the Restoration and the interactions of some of the figures involved is provided by a consideration of the designation of two constellations by Englishmen during the period. A closer examination of celestial planispheres produced in the Restoration period shows that (like the globes from which they derive) planispheres had extensive applications as calculating instruments. Many had a multitude of functions beyond the merely illustrative, some having accessories to further enhance their usefulness. Finally, the investigation of an unusual silver celestial planisphere shows that a 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 results in a deeper understanding of any given artefact.