Georg Galgemair was a German mathematician and astrologer and a pupil of Philipp Apian. his work on proportional circles allowed the advance of gnomonics. This volume involves the reduction compass as well as numerous questions and uses of the proportional circle, while the Apianic part deals with the manufacture and use of direction finding instruments for astronomical and terrestrial applications.

Quarto, [16], 88, [4], 32 pages. In Very Good minus condition. Bound in modern patterned paper covered boards. Text blocks some mild wear and age toning to pages, title page with two small holes to woodcut border and a small red stain above one hole, and two pinprick worming holes to gutter of first five leaves. Both titles within architectural woodcut borders. Part one with 100 woodcut diagrams in the text. Second part is lacking two folding woodcut plates. Small red name stamp to front free end page. Text in German. SP Consignment. Shelved in Case 3.