- Museum number
Table clock; spring-driven movement now incomplete; formerly fitted with cross-beat escapement; steel escape-wheel has 300 finely cut teeth and is driven by a spring remontoire, which was rewound half-hourly by powerful spring-driven mechanism (now missing) which was housed in the wooden base; main dial indicates hours and minutes on separate chapter rings; central area marked with circles for the Equator and two tropics, horizon line and lines to indicate the Houses of Heaven, numbered I-XII anti-clockwise (designed for use at latitude 52); lower dial shows days of week and age and phase of moon.
- Production date
Height: 49 centimetres
Width: 32.70 centimetres
Depth: 23.30 centimetres
- Curator's comments
- Text from 'Clocks', by David Thompson, London, 2004, p. 46.
Johann Buschmann (attributed).
Table clock with cross-beat escapement
Augsburg, c. 1650
Height 49 cm, width 32.7 cm, depth 23.3 cm
Johann Buschmann the elder (1591-1662) was one of the leading clock-makers in Augsburg during the first half of the seventeenth century. A rare insight into his character exists in a description of him by Johann Martin Hirt, the son-in-law of the famous art agent Philipp Hainhofer (1578-1647) who said of Buschmann that he was never without a mug of beer on his bench and that he always made sure the Duke's latest order was being worked on when he saw him (Hirt) coming along the street to visit the workshop to check on progress. In spite of his liking for beer, there is no doubt that Buschmann was one of the most talented makers of his time.
When this clock was made, in the 1650s, the most recent refinement in clockmaking was the cross-beat escapement. Although this escapement is commonly attributed to the great clockmaker Jost Bürgi, it was actually invented by Jacques Besson, who published it in 1569. However, it was Bürgi who developed it and used it with great success in his precision regulators made for use by astronomers. In support of a Buschmann attribution to this clock are some fascinating drawings now in the Herzog August Bibliothek in Wolfenbüttel, including one of a clock with cross-beat escapement not unlike this example.
Of simple design, the clock has a typical Augsburg ebony base marked with a pine-cone, the mark ofthat city. Here, Buschmann puts the escapement to good use with a superbly made steel escape wheel with three-hundred teeth. Wheels such as this show well the accomplishment of the best German clockmakers in this period. To power the escapement, Buschmann has used another technical innovation also popularized by Jost Bürgi, the spring remontoire. A small secondary spring is designed to power the escapement directly and is periodically rewound by a large mainspring housed in the ebony base of the clock. Its purpose is to obviate the excessive differences in the power output of the mainspring should it be directly used to impulse the escapement. Sadly, the escapement and the astrolabic dial of this clock are now missing, except for the engraved plate which should underlay the rete (as pp. 24, 42). The small dial at the bottom shows the days of the week and has an aperture to show the moon's age.
Purchased in 1973.
- On display (G38/dc4)
- Acquisition date
- Acquisition notes
- purchased at Sotheby's London sale 22nd January 1973, lot 225.
- Britain, Europe and Prehistory
- Registration number