Max Pauly (optician)

Max Pauly (born November 15, 1849 in Halle an der Saale ; † April 26, 1917 in Jena ) was a German food chemist, industrialist and optician.

Youth and work in sugar production

Pauly first attended the trade school in Halberstadt and then studied at the universities in Berlin and Halle and at the technical university in Berlin. As early as 1878 he took over the management of the large Brottewitz sugar factory near Mühlberg ad Elbe , which is now part of Südzucker . Among many other improvements in sugar production, he invented the Paulykocher (1889). With this invention it was possible to boil juices under pressure, whereby a better heat utilization was achieved when evaporating liquids. As a result, coal consumption in the sugar industry fell by 30%.

Lenses for astronomy

Pauly was fascinated by the stars from an early age and wanted to make himself lenses for observation. He began in the early 1880s with small grinding experiments and the study of practical optics. At an exhibition in Görlitz in 1885 he saw a mirror telescope belonging to a Mr. Simple. With him he learned the first practical skills of surface processing in Potsdam and familiarized himself with the various methods of technology. The practical experience from his apprenticeship as a locksmith was useful to him.

He invented his own methods of rough processing the glass and examining the material and surfaces. For Pauly, the overriding principle was to design the shape of the lenses strictly according to their calculation and only to make the empirical correction caused by inhomogeneities in the glass. Aluminum buttons of previously unknown accuracy and testing apparatus of all kinds were constructed. He usually had the radii calculated by younger opticians he knew in Jena , after initially trying to make calculations himself. He placed particular emphasis on avoiding zones and invented special tricks to identify and prevent their creation as soon as possible. The extrafocal images of his later lenses showed a previously unheard-of freedom from zones that astonished every astronomer . Pauly also soon recognized a major source of error for most opticians in the tensioning of the lenses during feeding. He therefore avoided cementing as much as possible with large lenses. If this was not possible, he cemented with the greatest care to avoid tension in the lens. Later he also invented his own method to achieve the strict parabolic shape of his concave mirrors .

Until the beginning of the 1890s he only used machines with hand and foot operation, from then on machines with motors in the basement of his house. A polishing machine for surfaces up to 600 mm was created in 1895.

During this time, various fine optical products were created: telescope mirrors , prisms , prism sets, telescope lenses and eyepieces of all kinds. Some of them were assembled by opticians and sold on. But many lenses often went at very low rates lovers astronomers : Once Pauly was convinced that the person is seriously scientifically-operated and had no resources, he was very generous. During this period: a 6 " lens prism for Ógyalla (1886), two 10" lens prisms for Ógyalla and Héreny (1893), (with one of them Eugen von Gothard photographed his nebulae spectra ), an 8 "lens for personal use (1888), a 6 "lens for Grinenko and another for Philipp Fauth (1891).

In the years 1891–94 Pauly carried out experiments with apochromats from the new glasses from Schott . Although they brought complete optical success, they also showed the instability of these first new types of glass. They encouraged the continuation of the successful melting tests at Schott. A 7 "apochromat was created for the Jena observatory , a 6" apochromat for the Berlin Urania , and a 7 "apochromat for Fauth, with which he made his parallel observations with Leo Brenner . Experiments with Gauss lenses followed , which indirectly led to the 25 cm achromat from Max Wolf .

At the beginning of the 1890s, Paulys built his own observatory based on designs by his friend v. Konkoly mounted an 8-inch model and built a primitive dome. A passage instrument by v. Gothard and a Strasser pendulum clock completed Pauly's small observatory, which was mainly used to test new apparatus, but on which he also observed the sun and planets.

Through the relationships with the opticians in Jena and with Dr. Schott came into contact with Ernst Abbe , who respected Pauly's work. When Abbe decided to start manufacturing astronomical instruments at the Zeiss factory, he tried to win Pauly over for the project.

Work at Zeiss in Jena

In 1897 Pauly followed his call to Jena and set up an astronomical department at the Zeiss plant as a partner. The department soon gained a great reputation in the astronomical world for its work. The observation telescopes or military light signal apparatus, which were essentially designed by Pauly himself, also increased the level of awareness of Zeiss.

Several larger instruments emerged from the new institute under Pauly: the triple 150, 120, and 120 mm refractor for Simejis (1900-04), the 720 mm reflector telescope for the State Observatory Heidelberg-Königstuhl (1901-04) , the 640 mm objective prism for the Cape observatory (1902), the zenith telescope for the Jena observatory (1904–06), the 400 mm reflector telescope for Innsbruck (1903–05), a 1000 mm reflector telescope for the Hamburg observatory Bergedorf (1908–11), the 145 mm UV Petzval with 15 ° and 10 ° lens prisms for the Yerkes observatory in Chicago (1905, 1911), the triple 360 ​​mm refractor for the cantonal observatories de Neuchâtel (1908–10), the? "lens for the Berlin observatory (1908–11), the 350 and 300 mm lenses for Zurich (1908–11), the 340 mm astrograph for Bergedorf (09-11) , the 650 mm refractor for Babelsberg and the 1200 mm reflecting telescope for the same institute, begun in 1914 and unfinished because of the war.

Because of health problems, Pauly severed his relationship with the Zeiss factory in 1912. The hardships of World War I exacerbated his illness and resulted in his death on April 26, 1917.

swell

1. ^ Max Pauly , obituary by Max Wolf
2. ↑ Sugar-sweet freight from the Elbaue rolls south , Mitteldeutsche Zeitung of November 6, 2009
3. ↑ Carl Zeiss AG : "Carl Friedrich Gauß: Fundamental Work on Optimizing Optical Systems" ( Memento from December 12, 2005 in the Internet Archive ) (content only available in source code, can be read with programs such as cURL )