A shepherd's dial (also known as a pillar dial or cylinder) is a type of sundial that measures the height of the sun via the so-called '' umbra versa''. Its design needs to incorporate a fixed

latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...

, but it is small and portable. It is named after Pyrenean shepherds, who would trace such a sundial on their staffs. This type of sundial was very popular in the 16th, 17th, and 18th centuries.

History

Since the ancient Roman era, people have created sundials which tell the time by measuring differences in the sun's height above the horizon over the course of the day –

Vitruvius Vitruvius (; c. 80–70 BC – after c. 15 BC) was a Roman architect and engineer during the 1st century BC, known for his multi-volume work entitled '' De architectura''. He originated the idea that all buildings should have three attribut ...

describes them as . The earliest description of a shepherd's dial as known today was written by

Hermann of Reichenau Blessed Hermann of Reichenau (18 July 1013– 24 September 1054), also known by other names, was an 11th-century Benedictine monk and scholar. He composed works on history, music theory, mathematics, and astronomy, as well as many hymns. ...

, an 11th-century

Benedictine monk The Benedictines, officially the Order of Saint Benedict ( la, Ordo Sancti Benedicti, abbreviated as OSB), are a Christian monasticism, monastic Religious order (Catholic), religious order of the Catholic Church following the Rule of Saint Benedic ...

, who called it a . It was also known in the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

as a (Oxford cylinder). Such sundials did not need aligning north-south and so became very popular, appearing in Renaissance artworks such as Holbein's 1528 '' Portrait of Nicolaus Kratzer'' and his 1533 ''

The Ambassadors ''The Ambassadors'' is a 1903 novel by Henry James, originally published as a serial in the ''North American Review'' (NAR). The novel is a dark comedy which follows the trip of protagonist Lewis Lambert Strether to Europe to bring the son o ...

''.

Concept

Characteristics

Variants

A Slovenian shepherd's dial is a flat dial in the shape of a sector of a circle. It is hung vertically and measures the altitude of the sun. A movable peg adjusts for the changing seasons.

References

{{Reflist Sundials