Charting Comets & Renaming the Constellations

ASTRONOMY. COMETS. Weigel, Erhard (1625–1699)

Speculum Uranicum / Aquilae Romanae Sacrum / Das ist / Himels Spiegel / darinnen ausser denen ordentlichen auch die ungewöhnli- chen Erscheinungen des Himmels / mit gebührender Anführungen abgebildet / vornemlich aber 7 der im Gestirne des Adlers / jüngst- hin entstandene Comet / nebst einer neuen Himmels-Charte unter dem Adler des H. Römischen Reiches / dargestellt wird / von Erhardo VVeigelio, ...

Jena: bey Samuel Krebsen, in Verlegung Thomas Matthias Götzen, 1661


Quarto: 19.8 x 16 cm. [128] p. π1, ):(4, A-M4, a-c4


Modern wrappers. A very good copy with occasional foxing or mild browning and a few trivial stains. A few discreet marginal paper repairs. With an added engraved frontispiece, added engraved star map (in the form of a globe gore), four added woodcut plates, and a few woodcut diagrams within text.

A rare astronomical work by the astronomer Erhard Weigel, a teacher of Gottfried W. Leibniz. The engraved frontispiece shows a man holding a telescope, standing before the University of Jena, with other astronomical instruments (quadrants, sextants, a globe, etc.) in the extreme foreground. Above, the comet (now known as Comet Ikeya-Zhang) of 1661 can be seen within the constellation Aquila (the Eagle) just below Sagittarius. The globe shown in the engraving is outfitted with an "Astrodicticum simplex", an instrument devised by Weigel. The engraved plate by J. R. Schildknecht, similar to an engraved globe gore, shows the path of the comet of 1652 as it passes through the constellations.

Erhard Weigel (1625–1699) was professor of mathematics at the University of Jena and Weimar Court Mathematician. In his "Speculum Uranicum", Weigel proposed renaming the constellation, substituting figures from modern European heraldry and Christian symbols for the traditional mythological images. Thus 'Ursa Major' became 'The elephant of Denmark', 'Cygnus' became the 'Ruta and Swords of Saxony', 'Aquila' the eagle came to symbolize the House of Brandenburg, 'Lyra', the Lyre came to represent England, etc.

Weigel gives a list of 140 comets previous to 1661, and, surprisingly for a man who eschewed astrology, records disasters and misfortunes that accompanied their appearances. He concludes his work with examples of unusual meteorological and geological phenomena (meteors, windstorms, earthquakes) and their effects. The nova of 1572, for example, foretold the St. Bartholomew's Day Massacre. 

Weigel was a well-regarded maker of instruments and globes. His teaching and published work had an enormous influence on many German astronomers & mathematicians including Gottfried W. Leibniz, Johann Christoph Sturm (1635–1703) and Georg Christoph Eimmart (1638–1705). "Erhard Weigel, astronomer, astrologer, and mathematician, frequently attacked for his pansophic tendencies. In spite of his mathematical precision and the good astronomical observation it is rather the significance of comets which interests Weigel most." (Faber du Faur)

Zinner p. 582; Poggendorff II, 1283; Kenney 20; Brüning 1061; Pogg. II, 1283; Struve 17; Bircher A1193; FdF 1506-07; not in Hou-zeau-L.; Lit.: Klaus-Dieter Herbst (ed.). Erhard Weigel (1625–1699) und die Wissenschaften. Frankfurt a.M.: Peter Lang 2013