Graff, Kasimir Romuald

(b. Prochnowo, Germany [now Próichnawo, Poland], 7 February 1878; d. Breitenfurt, near Vienna, Ausria, 15 February 1950)

astronomy.

After graduation from the secondary school in Poznan, Graff began his studies of astronomy and physics in 1897 at the University of Berlin, from wich he obtained the Ph.D. degree in 1901. From 1898 he was employed at the Urania Observatory in Berlin. In 1902 Graff became assistant astronomer at the Hamburg observatory, and in 1909 when the latter was transferred to Bergedorf, he was appointed associate astronomer. In this position he was obliged to lecture on spherical astronomy. During World War I Graff served as an expert on geodetic surveys. In 1917 he received the honorary title of professor, and at the end of the war he continued photometric observations with instruments of his own design at Bergedorf.

In 1928 he was appointed full professor of practical astronomy at the University of Vienna. There he did his best to modernize the great university observatory. In order to avoid the difficulties in stellar photometry caused by the increasing electric illumination in Vienna, he spent several months every year on the islands of Mallorca and Šolta (Yugoslavia) equipped with instruments of moderate size. Forced to resign from the observatory after the German occupation of Austria in 1938, Graff reassumed the directorship in 1945 but retired three years later. He was a member of the Austrian Academy of Sciences and of the Academia Pontificia Vaticana.

Graff was one of the last of those pioneers in astrophysics who by visual observations promoted photometry and colorimetry, as well as planetary and lunar research. In his stellar photometers he used, instead of “nichols,” wedges of gray glass (1914), even copying them photographically in circular form (“Kreiskeilphotometer” [1926]). A combination of assorted wedges of blue and yellow glass for the gradual adjustment of color of an artificial star to that of a natural star was the main part of his colorimeter (1928). Most of his papers contain long lists of stars classified by magnitude and color-type. He made many drawings of the surface features of Mars during its oppositions in 1898, 1901, 1909, and 1924. He occasionally made other observations which cannot be described here in detail. He published valuable textbooks on geographical position-finding and on astrophysics and, in collaboration with M. Beyer, a star atlas.

BIBLIOGRAPHY

I. Original Works. Graff’s writings include Grundriss der geographischen Ortsbestimmung (Berlin–Leipzig, 1914; 2nd ed., Berlin, 1941; 3rd ed., 1944); Sternatlas, 2 pts. (Hamburg, 1925–1927), in collaboration with M. Beyer Grundriss der Astrophvsik (Leipzig-Berlin, 1928); and “Physische Beschaffenheit des Plane tensystems,” in Handbuch der Astrophvsik, IV (1929), 358–425, and VII (1934), 410–421.

Among his many papers are “Formeln and Hülfstafeln zur Reduktion von Mondphotographien and Mondbeobachtungen,”in Publikationen des Astronomischen Recheninstituts Berlin (1901); and “Ortsverzeichnis von 580 veränderlichen Sternen,” in Astronomische Ahhandlungen der Hamburger Sternwarte in Bergedorf, 1 (1909), pt. 3. He published at least 170 other papers, the great majority of which are concerned with stellar photometry and colorimetry; the remainder deal with observations of the moon, planets, comets, and eclipses. Most of these papers appeared in the Astronomische Abhandlungen der Hamburger Sternwarte in Bergedorf and Mitteilungen der Hamburger Sternwarte in Bergedorf (1909–1926); and Mitteilungen der Universitäts–Sternwarte, Wien, 1 (1931–1938) and 4 (1947–1950).

II. Secondary Literature. On Graff and his work, see Paul Ahnert, “Kasimir Graff,” in Sterne. 26 (1950), 186–187, with portrait; Wilhelm Becker, “Kasimir Grafft †,” in Astronotnische Nachrichten, 279 (1950), 141–142: and Victor Oberguggenberger, “Kasimir Romuald Graff,” in Almanach. Österreichische Akademie der Wissenschaften, 100 (1950), 352–358, with portrait.

Konradin Ferrari D’Occhieppo