Astronomical Compendium, Later 16th century
Record status
Individual type · partial
Period
Later 16th century
This astronomical compendium is constructed from gilt brass and silver in the form of a small book measuring 62 x 56 x 14 mm. It features a curved spine with decorative projections, book clasps, and engraved edge lines simulating pages.
Attributed to Christoph Schissler, the instrument functions as an integrated set of scientific tools. The exterior top cover contains a geographical astrolabe with a rete and rotating longitude plate. The interior features a horizontal string-gnomon sundial equipped with three interchangeable silver plates for varying latitudes and a recessed compass. The underside of the cover includes a map of France surrounded by a 16-point compass rose, while the inner back cover displays a lunar volvelle for tracking moon phases and aspects.
The exterior back cover features an orthographic Rojas projection of the sphere, enabling calculations for sunrise, sunset, dawn, and twilight.
Evidence at a glance
- Linked sources
- 1
- Photograph views
- 1
- Catalogue references
- 0
Counts describe this entry’s documentation, not authenticity, rarity or completeness. Photographs may show one specimen; check each caption and licence.
Technical characteristics
- Type
- Augsburg astronomical compendium
- Materials
- Gilt brass and silver
- Dimensions
- 62 x 56 x 14 mm
- Place recorded
- Augsburg
- Place of Origin
- Augsburg
- Maker Attribution
- Christoph Schissler
- Compass Directions
- 16 directions
- Maker / attribution
- Attributed to Christoph Schissler
- Sundial Latitude Range
- 38 to 55 degrees
Design
- Visible features
- • The book-shaped case features two functional metal clasps. • A fixed suspension ring is mounted on the upper edge of the device. • The compass needle terminates in a T-shape at the north point. • The sundial uses a string gnomon held by a central support.
- Design and Construction
- The object is crafted in the shape of a book, utilizing gilt brass and silver. The case incorporates a curved spine with two projections, and the edges of the central box are engraved to resemble page leaves. Two book clasps maintain the closed position, and a fixed ring is provided for suspension. The interior layout is segmented into distinct working areas, including a horizontal sundial with interchangeable latitude plates, a compass with a silvered base plate, and a lunar volvelle. Foliate engraving decorates the various surfaces, and specific mechanical features include an integrated spring barrel to maintain tension on the sundial string.
- Compass and Sundial Components
- The central sundial utilizes three loose silver plates, each covering a three-degree latitude range between 38 and 55 degrees. The string gnomon passes through a small cylinder and is held taut by a spring barrel located underneath the plate. The 18 mm diameter compass is viewed through circular apertures in the sundial plates. It is decorated with enamel-colored pointers and is marked in abbreviated French. The north needle ends in a T-shape, and the compass bowl base features an engraved cockerel.
- Geographical and Astronomical Functions
- The outer cover acts as a geographical astrolabe with a rete and a longitude scale for the earth. The geographical map, centered on France, uses circular indentations to represent towns and includes a radial index with a sliding cursor. The Rojas projection on the back cover allows for complex calculations regarding solar events. It provides data for sunrise, sunset, dawn, and twilight. The lunar volvelle on the interior displays moon phases, lunar age, and aspect diagrams involving geometric symbols.
Identification
- Inventory Number
- 45366
- Source note
- Facts transcribed from the linked source listing or collection record. Attribution and specifications are source-reported and have not been independently authenticated.
Catalogue references
No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.
Research required
- Research required: The string-gnomon support is considered a possible replacement.
- Research required: The index for the geographical astrolabe is detached.