Equinoctial Sundial by Thomas Tretsch
name: label: maker
content: Tretsch, Thomas
notes: label: Description
content: This brass universal equinoctial ring dial consists of a meridian ring, hour ring, rotating crosspiece or bridge, and suspension ring / handle. The meridian ring is calibrated on one side for solar altitude by a nautical quadrant from 0 to 80 by single degree. The hour ring is calibrated on one side from I to XII x 2 by I. The bridge contains a pinhole gnomon sliding over a calendar scale calibrated and lettered by month, with zodiacal sign on verso. The opposite side of the meridian ring contains a list of several European towns and latitudes which are carelessly and faintly engraved. The suspension ring is screwed into a ferrous metal casing which fixes it at 33 degrees. This support casing may not be original since 33 degrees is well south of the cities given on the dial. Tretsch was a maker from eastern Germany or Austria. Although there are some attempts at decorative work on this dial, including a metal fish screwed to the reverse side, the workmanship overall is poor.
label: Location
content: Currently not on view
topic: label: Subject
content: Mathematics
label: Subject
content: Timekeeping
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Science & Mathematics
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.336093
label: accession number
content: 316529
label: catalog number
content: 336093
objectType: label: Object Name
content: Sundial, Equinoctial
physicalDescription: label: Measurements
content: overall: .5 cm x 7.6 cm x 9 cm; 3/16 in x 3 in x 3 17/32 in