1804 Walch Celestial Chart w/ Manuscript Record of Great Comet of 1811

This is an 1804 celestial map, with extensive manuscript annotations, prepared by Johannes Walch. Aside from its aesthetic qualities, the chart is noteworthy for its manuscript annotations recording the Great Comet of 1811. Overall, the chart captures the state of astronomical knowledge at the time, including the discovery of Uranus by astronomer William Herschel (1738-1822).

A Closer Look

The top part of the sheet contains a dual hemispheric depiction of the heavens, the 'midday' or northern hemisphere at left and the 'midnight' or southern hemisphere at right, with both hemispheres ringed by a border with the months of the year subdivided into sections. Constellations are labeled throughout in German or, in some cases, Latin, while the constellations' individual stars are labeled according to the Bayer system of classification. Stars, including nebula stars, are represented with symbols reflecting their size, as indicated in a small legend on the left. The hemispheres, particularly the right, contain significant manuscript annotations, including illustrations and dates of major comets, such as the Great Comet of 1811. Below the meeting point of the hemispheres are two quotes from poems, one by the ancient astronomer Marcus Manilius (c. 1st century CE) and the other by 18th-century naturalist Albrecht von Haller (1708 - 1777).

The bottom portion of the sheet traces the seasonal deviation of the stars and also the recent (c. 1790s) movements of Mars, Jupiter, Saturn, and a body marked 'Herschel 1787.' This was perhaps one of the moons of Uranus (Oberon and Titania) discovered by German-British astronomer William Herschel that year, but more likely a reference to his earlier (1781) discovery of Uranus itself; the name of the new planet was not settled for decades and it was commonly referred to after its discoverer in these years. Herschel and his sister Caroline (1750-1848), who was his lifelong collaborator, pioneered many innovations in telescopy and astronomical spectroscopy that set off a period of improved astronomical observations.

Publication History and Census

This chart was prepared and published by Johannes Walch in Augsburg in 1804. Subsequent editions were published in 1820, 1826, 1833, and 1836, which, like the present edition, are quite scarce in institutional collections, especially outside of Germany. The only known institutional holding in North America is at Harvard University.