Sundials
Reference articles are in English.
John Carmichael’s carved stone Equation of Time sundial. Source
Description
A sundial indicates time through the relationship of a shadow to marked hour lines. Stone can form its face, inscription or supporting sculpture. The layout depends on the type of dial, latitude and orientation. Horizontal, vertical and polar forms use different arrangements.
History
Shadow-based timekeeping has an ancient history, including surviving Egyptian dial forms. Sundials later became familiar architectural and garden objects, joining astronomical calculation with inscriptions and decorative design.
Commissioning
The location and orientation should be established before the dial is calculated. The agreement should identify who checks the geometry and the time system shown. Material, lettering, scale and setting should be considered with its intended use as a timepiece.