Hans Dorn (mechanic)

Hans Dorn (* between 1430 and 1440 in Austria ; † 1509 in Vienna ) was an Austrian Dominican and mechanic who created novel sundials and astronomical instruments on the threshold between the Middle Ages and modern times .

Life

There is very little information about Hans Dorn. Between 1450 and 1461 he studied with Georg Peuerbach and Johannes Regiomontan in Vienna. After that he apparently became a Dominican, but was in the service of the Hungarian King Matthias Corvinus and lived in Buda . There he developed most of his devices. In 1478 he came to Nuremberg on behalf of Corvinus to buy the books and equipment that Regiomontan had left behind. He apparently stayed there until the council's negative answer of February 20, 1479. During this time he was characterized by the words “devout spiritual brother”. After the death of Corvinus (1490) he returned to Vienna, where he apparently lived until his death. However, he continued to maintain relations with the Hungarian royal family, because in 1501 he gave the combination of the star clock and the box sundial built in 1491 to King Ladislaus II.

Some of his devices were taken to Krakow by the astrologer and high cleric of Corvinus, Martin Ilkusch († around 1493), and given away to the Jagiellonian University . In 1494 they were introduced to the professors there. There are no souvenirs of Hans Dorn in the Dominican monastery in Vienna.

Dorn's rifle sundials were the first to contain "a disk with the network of curves on the front of the astrolabe with the curves of the equator, the two tropics and the hours of unequal length (planetary hours), apparently to convert the ordinary hours into the planetary hours ". The front of the astrolabe is the stereographic projection of the celestial circles on the tangential plane in the North Pole. He also combined two instruments into one: he created a star clock with a small box sundial and a box sundial combined with a moon dial .

Only the sundial from 1491 is clearly identified with the name "Hans Dorn". Because of some peculiarities that are common to this sundial and some other devices, they are attributed to him. They all have certain advantages of the Viennese school and can therefore only have been built by a very skilled mechanic like Hans Dorn. Similarities between the can sundial from 1476 and some devices made between 1455 and 566 suggest that Dorn, even as an assistant to Peuerbach, distinguished himself through careful work. Only Hans Dorn can be considered as the builder of the two sundials on the churches in Košice (Kaschau) and Spišské Podhradie (Spiš Chapter) in Slovakia, which at that time belonged to Hungary.

Received works

• 1476 sundial made of silver-plated and gold-plated brass (63 × 63 mm, inscription "Istud instrumentum ad omnem regionem in universo mundi 1476"; Württembergisches Landesmuseum Stuttgart, inv. WM 12364 )
• 1477 sundial at Košice Cathedral (a south clock with pole rod, in 1886 the dial was whitewashed and numerals blackened)
• Sundial at the church in Spišské Podhradie (a very similar clock to the one from 1477 in Košice)
• 1479 Square sundial made of gilded brass (65 × 65 mm, inscription "MARIA HILF VNS AN 1479" and "ISTVD AD OMNEM REGIONEM", Adler-Planetarium Chicago, Collection Mensing, Inv. 288)
• 1480 Brass celestial sphere with a frame with an attachment (circumference 132 cm, total height 124 cm, Jagiellonian Library Cracow)
• 1481 Square sundial made of gilded brass (like the one from 1479, but with a different directory, | Museum of the History of Science, Oxford, Inv.G425)
• Brass box sundial with 5 hinges, which are held together by a pin), with a moon clock (86 × 86 mm, Museum für Kunst und Gewerbe Hamburg , Inv. 1893.2)
• 1486 Brass astrolabe (diameter 452 mm, Krakow University Observatory)
• Brass Turkish device (not complete; preserved: base plate, equatorial disk, ecliptic disk with its top of the broad disk together with the hanging semicircular disk; Krakow University Observatory)
• Armillary sphere of the Jagellon globe (probably given a new globe in 1515 and also changed later, Jagellon University Krakow)
• 1491 Silver- plated copper star clock with a box sundial (inscribed: "Hans Dorn Preacher Order on Vienna 1491", British Museum London, inv. 94.6-15.1)

Notes and individual references

1. ↑ ^{a b c} Ernst Zinner: German and Dutch astronomical instruments ... , p. 293
2. ^ Ernst Zinner: German and Dutch astronomical instruments ... , p. 101
3. ^ Ernst Zinner: German and Dutch astronomical instruments ... , p. 165
4. ^ Ernst Zinner: German and Dutch astronomical instruments ... , p. 297
5. ↑ Illustration in: Mensing Collection. Ancient scientific instruments. Catalog , Amsterdam 1924
6. ↑ Illustration in: Life and Work of Johannes Müller von Königsberg, called Regiomontanus , Munich 1938, Fig. 89–90 (= series of publications on Bavarian national history)
7. ↑ Illustration in: Ernst Zinner: German and Dutch astronomical instruments ... , plate 25.1
8. ↑ Figures in: Life and Work of Johannes Müller von Königsberg, called Regiomontanus , Munich 1938, Fig. 76–77 and L. Birkenmajer: Marcin Bylica z Olkusza , Kraków 1892, pp. 94–98
9. ↑ Illustration in: Life and Work of Johannes Müller von Königsberg, called Regiomontanus , Munich 1938, Fig. 92
10. ↑ Illustration in: Ed. Luther Stevenson: Terrestrial and celestial globes , New Haven 1921

literature

• Ernst Zinner : German and Dutch astronomical instruments of the 11th-18th centuries Century , Munich: Beck 1956 (reprint 1979, ISBN 3-406-03301-6 ), especially pp. 292-297