Instruments · Plane astrolabe
Plane astrolabe attributed to Vincenzo Viviani, Italy, 1645
- Maker / attribution
- Vincenzo Viviani (attributed)
- Date
- 1645
- Historical period
- Early Modern Horology (1600 – 1750)
- Country of origin
- Italy
- Place
- Italian
- Object type
- Plane astrolabe
- Materials / technique
- copper, wood, cardboard
- Dimensions
- diameter 228 mm
- Holding institution
- Museo Galileo, Florence
- Accession / object no.
- Inv. 1289
- Credit line
- Museo Galileo, Florence
- Catalogue title (original)
- Plane astrolabe (English)
View the source record ↗ (opens another website in a new tab)Suggest a correction
Record summary
Held and catalogued by Museo Galileo, Florence (object number Inv. 1289), this is a plane astrolabe attributed to Vincenzo Viviani, made in Italian, Italy, dated 1645. The Atlas places it in the Early Modern Horology period (1600 – 1750) of its Instruments collection. Materials and techniques recorded by the source: copper, wood, cardboard. Recorded dimensions: diameter 228 mm. The record is illustrated with 2 photographs.
Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.
Catalogue description
Catalogue description — Museo Galileo
This astrolabe, from the Vincenzo Viviani bequest, seems to have been made for teaching purposes, perhaps by the scientist himself. The wooden, copper-edged mater carries: a tympanum with the celestial vault; a tympanum with the main stars; a copper tympanum for latitudes 38° and 43° (from Sicily to Pisa); a cardboard tympanum for latitude 43° (Pisa); a rete; and a cardboard disk with a shadow square. The limb, rete, and index are made of copper, as is the back, which features an alidade, a disk with shadow square, a windrose, and a table for ecclesiastical dates.
Historical context
Early Modern Horology (1600 – 1750)
Huygens' pendulum and balance spring transform accuracy; English makers develop the anchor and deadbeat escapements.
Pocket sundials, Butterfield dials and sandglasses remained essential companions to imperfect clocks; navigators used sandglasses and the log line; observatories began to combine telescopes with pendulum clocks.
Read the period in the timelineMore instruments from this periodEarlier: Renaissance Horology
Atlas type guide
Astrolabes, quadrants and astronomical compendia
The planispheric astrolabe is a two-dimensional model of the sky. A pierced rotating star map (the rete) turns over a plate engraved for a particular latitude; by aligning a star or the sun with its observed altitude, the user can read the time of day or night, the time of sunrise and sunset, and solve many other astronomical problems. Developed in the Hellenistic world and refined by astronomers in the Islamic world from the eighth century, it reached Latin Europe through al-Andalus.
Quadrants, compendia, armillary spheres and later orreries belong to the same family of instruments that model the heavens. They were teaching tools, status objects and practical time-finders. Many surviving examples are signed and dated, which makes them important evidence for the history of instrument-making workshops in Baghdad, Isfahan, Lahore, Toledo, Louvain, Nuremberg, London and elsewhere.
What to look for
- The latitudes engraved on the plates — they show which cities the instrument was made for.
- The script and calendar used: Arabic or Persian inscriptions, abjad numerals, Hebrew or Latin text indicate tradition and region.
- The design of the rete: the number of named stars and the style of the star pointers changes by region and period.
- Shadow squares, unequal-hour lines and zodiac scales on the back (dorsum).
- Signatures, dedications and dates, often hidden on the throne (kursi) or the back.
Dating clues
- Signed and dated astrolabes allow precise dating; undated ones are attributed by star positions on the rete, which shift slowly through precession.
- Gothic-style retes with tracery are typical of European instruments of the fourteenth and fifteenth centuries.
- Printed paper astrolabes and planispheres became common from the sixteenth century onward.
General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.
Related records
Instruments · 1575–1625
Sand-glass set (x4) fitted into an ebony case, inlaid with ivory. Italian, c1600
Victoria and Albert Museum, London
Instruments · 1601–1700
17th century Italian four-way hour glass with brass stand
Science Museum Group, London
Instruments · 1601–1700
Italian four-way hour glass with wooden frame, 1601–1700
Science Museum Group, London
Instruments · 1601–1650
Nocturnal, brass gilt, diameter 2 3/4in. Italian, 1601–1650
Science Museum Group, London
Instruments · 1601–1700
Quadrant sundial of ivory, Italian hours, for use at latitude 44°, Italy, 1601–1700.
Science Museum Group, London
Instruments · 1651–1700
Azimuth Sundial, brass, "Jacobus Lusuerg" fa: Romae
Science Museum Group, London
Instruments · 1677
Wooden column sundial, showing Italian hours, signed and dated 1677. Probably Italian.
Science Museum Group, London
Instruments · 1701
Portable equatorial or equinoctial sundial by Dominicus Lusuerg, 1701
The Metropolitan Museum of Art, New York