Errors in drawing the nine regular sundials, 1745.

Engraving showing several different types of sundial. Illustration from 'Mathematischer Atlas' (Mathematical atlas) by Tobias Mayer (1723-1762) published in Augsburg in 1745. Each plate has descriptive text on either side; some have contemporary hand colouring. Mayer was heavily influenced by Christian von Wolff's work, through which he had taught himself mathematics. The plates duplicate Wolff's choice of subjects - arithmetic, geometry, trigonometry, astronomy, geography, chronology, gnomonics, fortification, artillery, civil architecture, optics and mechanics.