bavarikon4UDescription
In 1911, at an auction in Paris, the Deutsches Museum acquired a square, equatorial table sundial made of gilded copper, particularly richly decorated with scales and inscriptions. The inscription "fecit E. habermel" proves that it is a signed instrument by Erasmus Habermel. One of the best experts on early modern German astronomical instruments, Ernst Zinner, wrote about him that he was "not one of the most imaginative, but certainly one of the most skilful and accomplished masters of the 16th century". Numerous instruments from his workshop are known today (including an astrolabe, cf. Deutsches Museum, DMO, Inv. No. 29028) and are major highlights in the important instrument collections.
It is unknown when and where Habermel was born – probably in the 1550s. The earliest known work signed by him was created in 1576. It is also unknown when he came to Prague, which Rudolf II, elected emperor in 1576, made his permanent residence. The court of the emperor, who had been raised strictly Catholic in Spain and who brought the astronomers Tycho Brahe and Johannes Kepler to Prague, became the centre of the modern natural sciences, which were still in their infancy. Their current issues and requirements are reflected in the quality of the instruments produced there. Those by Habermel combine high precision and quality craftsmanship with impressive aesthetic design. The most important date in his career was probably 1 October 1594, when he was appointed astronomical and geometrical instrument maker. His date of death, 15 November 1606, is also known from the court records.
The Habermel sundial at the Deutsches Museum, whose exact date of origin is unknown, bears a compass with easterly declination on its openwork base plate as well as a network of curves for converting the hours. On the underside of the base plate there is a projection of the northern hemisphere ("OCASSVS SOLIS") onto the meridian plane and the scale of the signs of the zodiac – the corresponding rule is missing – and the table of day and night lengths. The dial of the sundial shows the compass rose divided into 32 and inscribed in Dutch on the inside and twelve hours twice on the outside, each with eight divisions. It is set parallel to the equatorial plane with two rods on the "Eleuatio Poli" notches made in the sides of the base plate. A continuous rule is attached to rotate around the centre with a tip at one end and with the vertically hinged flat gnomon at the other. This has a larger hole at the top and two smaller ones below, through which the sun’s rays fall. Peculiarly, the sundial is only useful for summer, as the lower side of the equatorial plate is only marked with the curve "HORÆ DIVRNE CV[M] VVLGARES TV[M] / PLANETARIÆ INTER SE ADEQVATÆ", the ordinary hours and the planetary hours, as well as a table of the daily planets ("TABVLA PLANETARIVM DIEI"). (Source: Petzold 2003)