Elliptical, Or Azimuthal Horologiography (1654)

This brilliant work, far ahead of its time, details Foster’s development of analemmatic, circular, and diametral sundials and their generalizations. (The title appeared earlier in compressed format as part of The Analemmatic Sundial Sourcebook – it is available here as a separate volume.) Its four sections are: Elliptical, Or Azimuthal Horologiography; Circular Horologiography; Rectilineal Or Diametral Horologiography; Elliptical Horologiography. It was prepared for the press by Edmund Wingate and John Twysden two years after Foster’s death.