The Tower of the Winds in Athens included both a sundial and a water clock for telling time. A canonical sundial is one that indicates the canonical hours of liturgical acts, and these were used from the 7th …

Dec 22, 2025 · Sundial, the earliest type of timekeeping device, which indicates the time of day by the position of the shadow of some object exposed to the sun’s rays. As the day progresses, the sun …

This set of pages explains, with diagrams, how a sundial works. It begins with the simplest (equatorial) dial where the shadow of a stick (the gnomon) falls on hour lines every 15 degrees apart, and then …

Learn what a sundial is, how it works, its invention, types, and uses. Discover easy diagrams and key facts for exams and projects.

Volunteers from the Analemma Society and NASS demonstrated a number of sundial types and provided paper sundial cut-outs that were enjoyed by children, students, parents and teachers alike.

A sundial is a device that measures time by the position of the Sun. In common designs such as the horizontal sundial, the Sun casts a shadow from the gnomon, which is a thin rod straight edge, onto …

In its simplest form, a sundial consists of a flat surface, known as the dial plate, marked with hour lines and a raised arm or stick called the gnomon, which casts a shadow across the dial as the sun moves …

Nov 2, 2024 · A sundial operates based on the Earth’s rotation and the sun’s movement across the sky. The most essential component of a sundial is the gnomon, a stick or triangular object that casts a …

Sep 6, 2019 · A sundial uses the movement of the sun to keep track of time. There are several varieties, but one of the most basic consists of a thin rod or triangle -- called a gnomon -- and a flat circular or …

Mar 10, 2025 · Sundials have been used to measure time, based on the Sun, for thousands of years. This simple device can be made up of nothing but a flat dial and a gnomon (the “pointer” that casts …