Shan Macdonald, Curatorial assistant for Scientific Instruments selected this object from the Hunterian Museum's collection. Shan writes - This beautiful instrument was made in the early 18th century by the French mathematician Nicolas Bion (1652-1733).
Bion's workshop was located within the historic Quai de l'Horloge, Palais de Justice, Paris. He worked by royal appointment as a maker of mathematical instruments to Louis XIV and Louis XV, of France.
This is a horizontal compass sundial, made of gilded silver. It is of 'Butterfield' type, named after English manufacturer Michael Butterfield, who popularised the adjustable bird gnomon.
The sundial can be used over a number of different latitudes, and is inscribed with Babylonian (beginning at sunrise) and Italian (beginning at sunset) hours. The latitudes of notable European cities are engraved on the reverse.