This exceedingly rare, large-format broadside was issued in Nuremberg as a private commission for the Bohemian astronomer and mathematician Ignaz Kautsch in the period immediately leading up to the Solar Eclipse of September 5, 1793. The general purpose of the work is to provide people living in the regions where the eclipse would be visible, mainly in Europe and Western Asia, with a guide as to when precisely the event would occur above their geographical locations. The content of the broadside is influenced by the general conception of the workings of eclipses as articulated within Kautch’s magnum opus, Geographia Practica Seu Methodus Facilis Ope Projectionis Sphaerae Terraqueae Construendi Quaevis Planisphaeria, Mappas Geographicas Generales Et Speciales, Cum Eorundem Artefactorum Figuris et Usu. Accedunt: Astronomia Ad Geographiam Et Nauticam Applicata, Seu Copiosa Subsidia Astronomica Ope Eclipsium Solis, Lunae, Sattelitum Jovis,…(Skalica, [Slovakia], 1784, subsequently reissued in St. Petersburg, 1800), a work that was highly influential in institutions of higher education throughout Central and Eastern Europe. To be clear the present work, issued nine years after Kautsch’s book, does not merely mimic the conceptions as previously outlined, but adapts the author’s conceptions specifically to the Solar Eclipse of September 5, 1793.
The broadside consists of four related parts. The large and fascinating diagram, that dominates the upper right of the composition, depicts the path of the moon as it traverses the face of the sun. The extensive and precisely detailed text below explains the operation of the eclipse and gives instructions to the reader regarding the use of the diagram, requesting them to cut out a disc of paper (from a external source that was not provided by the original publication) that can act as a volvelle, which can be slid across the diagram, simulating the position of the moon at various times during the eclipse.
Curiously, the broadside was originally coated in a thin layer of egg-white, so allowing a volvelle to effortlessly slide across the paper. As the aged egg-white had since darkened and threatened to make the paper brittle, it has recently been professionally removed, so restoring the broadside to its original coloring.
The map, which dominates the upper left of the broadside, embraces much of the Northern Hemisphere from eastern North America, in the west, all the way to India, in the east; embracing all of the places where the Solar Eclipse of September 5, 1793 would be visible. The map shows that the eclipse would pass directly along line running from Hudson’s Bay (Canada); then over across southern Greenland and Iceland; an then above northern Scotland, Denmark, northern Germany and Poland; then crossing the Black Sea and the Caucuses; whereupon it would then cross northern Persia (right over Tehran), before passing above northernmost India. The map also shows that the Eclipse would be visible, to varying decrees, in locations somewhat distant from the direct line of its path, including pretty much all of Europe, but also from cities such as Boston, Cairo, Isfahan, Agra and Goa.
Interestingly, the table, in the lower right part of the broadside, gives the precise times during which the Eclipse would first appear, reach its height, and the disappear from view at different cities, including Amsterdam, Lisbon, Isfahan, Warsaw, Jerusalem, Rome Berlin and Paris, amongst many others.
The broadside was published by the leading cartographic printer Homann Heirs of Nuremberg (their imprint appears lower right), and was evidently a private commission from Ignaz Kautsch. Curiously, at the end of the explanatory text (lower left), it is explained that the broadside was available for sale at the Trattner & Hörling bookstore in Vienna (for the price of 2 Florins, 30 Kreuzer), an establishment long associated with Kautsch.
Ignaz Kautsh (1729 - 1812) was a Bohemian Pietist priest who became a prominent astronomer and mathematician, serving as a professor at several different ecclesiastical universities in Central Europe during his long career. He issued a number of publications, including the aforementioned Geographia Practica (Skalica, 1784); but also the Transitus Veneris ante discum solis cum tabula anno 1874 die 9 decembris Europæ ante meridiem spectabilis cujius elementa (Brno, c. 1780); Neuer Wiener Stadt- und Meilen- Zeiger (Vienna, 1787); Planetometria sive dimensio distantiae et magnitudinis coelestium luminarium solis et lunae secundum (Vienna, 1788); and the Supplementum ad dissertationes quas planetometriae adjunxit (Prague, 1796).
The present broadside is extremely rare, commensurate with the low survival rate of such privately issued separate works of the period. We can locate only two other examples, in the collections of the Universitätsbibliothek Bern and the Staatsbibliothek zu Berlin - Preußischer Kulturbesitz.
References: OCLC: 956283195.