Universal ring sundial 18th century

Jonathan Sisson's "Universal Ring Sundial" from the 18th century is a brass instrument for telling time using the sun's position. The intricate design features two rings and a central gnomon, a rod that casts a shadow to indicate the time. The ring sundial is a portable device, allowing for timekeeping across various locations. This object represents the ingenuity and precision of 18th-century scientific instrument making. Sisson, a renowned English clockmaker, was known for his innovative designs and contributions to the field of horology.