Description

• diameter: 6 cm,
• made of solid brass
• instrument is fully functional
• beautifully detailed to exact replica precision
• information booklet included
• packed in elegant pouche
• instrument will indicate the solar local time

History and usage

Although known as the astronomical ring, this instrument evolved directly from the armillary sphere, which dates back to Ptolemy times.

Armillary sphere is an astronomical model of the celestial sphere. The instrument is built of graduated metal rings (armillae) linking the poles and representing the equator, the ecliptic and meridians.

Our sundial is the model that has been simplified to two main rings, one to be aligned with the equator, one with the meridian.

The first sundial of this type was most likely designed by Anthony Thompson in 1652 and its use was widespread during 18th century.

The astronomical ring works with lattitude and time of year to give the correct time today.

The pointer located on top of the meridian ring (outer ring) is used to point to the desired lattitude. The inside ring is used as the hour ring. In the middle you have the bridge which has a slidder to adjust the month. In the middle of the slider is a small hole which the sunlight passes through to reveal a sun spot on the inside of the equatorial (hour) ring, which in turns gives you the time.