The collections
Gerard Hulst Van Keulen's Planisphaerum CoelestumSouthern Hemisphere
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Two rare and exciting acquisitions were made recentlyof late eighteenth century Dutch celestial charts of the Southern Hemisphere. Completely devoid of any authorship, title or imprint, the charts are believed to be first and second proof copies of Gerard Hulst van Keulen's Planisphaerum Coelestum, Southern Hemisphere, published in 1798. It is not known if further proofs were made before the final chart was published. Gerard Hulst van Keulen was a member of the distinguished van Keulen family, which was amongst the most prolific and highly respected families of Dutch cartographers active between about 1680 and 1822. While the family was renowned for its sea-charts and associated material, Gerard's arrival in the family business in 1757, along with his brother Cornelis Buys, heralded a change in direction. More books appeared and there was greater diversification in the cartographic side of the business. |
Above: Detail of a proof sheet of Gerard Hulst Van Keulen's Planisphaerum Coelestum showing Aquarius, Capricornus and Sagittarius |
The two celestial charts reflect this diversification. Large in format, measuring 58 cm in diameter, the charts clearly show the Southern Hemisphere celestial formations as they were largely understood at the end of the eighteenth century. Typical 1800 stellar representations are depicted by six different symbols, each marked by its Bayer representation. Circles of latitude are drawn every 30 degrees except that through the first point of Leo and Aquarius there are separate parallels to the ecliptic drawn every ten degrees. The ecliptic is drawn but not graduated.
The equator is drawn; it is also graduated for 360 degrees and numbered every five. Hours are graduated 0_XXIV and numbered every 1 hour and 30 minutes. Alongside the equator is a calendar with the days numbered and the names of the month in Dutch.
Ptolemaic constellations of the zodiac as well as north and south of the zodiac are shown, as are the non-Ptolemaic constellations invented by Plancius around 1597. Some manuscript straight lines are drawn on the map, connecting the very bright stars.
Extensive manuscript annotations on the first proof (illustrated) have been transferred and engraved on the second proof. Here, a new scale has been added to the ecliptic, some star positions corrected and the manuscript straight lines of the first proof appear in engraved form. Additional manuscript annotations have been added to this state.
The large format and clarity of the maps, together with the nature and incorporation of the manuscript annotations into the proofs, provide a remarkable record of the interpretation of the southern skies during the eighteenth century.
Please address any comments and enquiries to The Editor, Gateways: lkirwan@nla.gov.au