Hell (or Höll), Maximilian

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Hell (or Höll), Maximilian

(b. Schemnitz [now Banská Štiavnica], Slovakia [now Czechoslovakia], 15 May 1720; d. Vienna, Austria, 14 April 1792)

astronomy.

Hell was the youngest of the three sons of Matthias Cornelius Hell, the chief engineer of the royal mines at Schemnitz, then in the kingdom of Hungary. After attending the primary school at Schemnitz and the secondary school at Neusohl (now Banská Bystrica), he decided in 1738 to enter the Jesuits, which would require some twelve years of moral and scientific training. He first spent two years of probation at Trenčín, Hungary (now Czechoslovakia). Next he was sent to the University of Vienna to study philosophy, which then comprised a very wide range of disciplines, including mathematics, physics, and astronomy. J. Franz, who was in charge of teaching these sciences, soon became aware of Hell’s aptitude and allowed him to participate in his astronomical observations at the Jesuit College observatory. In 1746 and 1747 Hell taught mathematics and physics in the secondary school at Leutschau, Hungary (now Levaca, Czechoslovakia). He then returned to Vienna, finished his studies in theology, and in 1751 was ordained a priest. He received the Ph.D. from the University of Vienna in 1752.

Next Hell was sent by his order to Kolozsvár (now Cluj, Rumania), then part of Hungary. There he was in charge of the construction of a new college building, including an astronomical observatory. At the same time he taught mathematics, physics, and history at a secondary school. For this purpose he wrote textbooks and performed physical experiments, especially in magnetism.

Hell’s scientific career proper began in 1755, when, in connection with a general reform of the University of Vienna, the Hapsburgs decided to establish a great central astronomical observatory. Its basic equipment was to be the instruments of the late imperial mathematician and geodetic surveyor, J. J. de Marinoni, who had made his house, on a relatively favorable site at the edge of Vienna, into an astronomical observatory. But since its distance of about a mile from the university was considered too far, it was decided to acquire only the instruments and to construct for them a four-story rectangular tower above the roof of the nearly completed new hall of the university. Hell, when he was appointed director of the new observatory, had to accept this improper decision. With great diligence he supervised the completion of the building, lectured in mathematics and astronomy, and was also in charge of instruction in technology, then called “popular mechanics.” His main task, assumed even before it was possible to perform observations at the new observatory, was the computation and publication of an annual astronomical ephemeris similar to the Connaissance des temps, the only such publication then in existence. Ephemerides were of vital importance both for the imperial navy and for the merchant fleet, as well as for geodetic surveys and exact mapping of the empire. Such practical aspects led to the promotion of astronomy by the public authorities and to large attendance of Hell’s lectures.

Hell was also greatly interested in pure science. Thus nearly all of the ephemeris volumes contain an appendix of scientific papers and observations by Hell himself, by his collaborators, and sometimes even by foreign astronomers. It was undoubtedly through this regular and useful series, as well as his other publications, that Hell’s scientific reputation spread throughout Europe. Christian VII of Denmark and Norway invited him to undertake an expedition to the isle of Vardö, near the eastern coast of Lapland, in order to observe the transit of Venus of 3 June 1769 and the solar eclipse occurring the following day. Emperor Joseph II agreed; and Hell, accompanied by J. Sajnovics and a manservant, started for Copenhagen in the summer of 1768. The major part of the journey from Copenhagen to Vardö was by sea, and they arrived in September 1768. At the village of Vardöhus, following Hell’s plans and under his supervision, the soldiers of a small royal fortress constructed a frame observatory with a separate room for living quarters. During the long winter there was time to adjust the precise clocks and the telescopes. On 3 and 4 June 1769, although the weather was somewhat cloudy, the observations could be made. The return journey was begun at the end of June, but Hell and his companions did not reach Copenhagen until 17 October. Wherever possible they performed meteorological, magnetic, and astronomical observations, the last with the aim of measuring geographic latitudes. They spent more than half a year at Copenhagen, partly to avoid traveling in winter but also so that Hell could deliver an extensive report of the results of the expedition to the Royal Danish Academy and obtain printed copies of this report. The group left Copenhagen on 22 May 1770 and reached Vienna that August.

In contrast with this successful expedition and his election as an honorary fellow of the academies of Trondheim and Copenhagen, the last two decades of Hell’s life were seriously affected by the widespread but unmerited suspicion—apparently first expressed by Lalande—that he had falsified, or indeed had never made, the observations of the transit of Venus. He was also upset by the abolition of the Jesuits in 1773, although it did not formally alter his position as director of the Vienna observatory. Indeed, he continued to be assisted by his former pupils Anton Pilgram and Franz Triesnecker, ex-Jesuits like himself, in the edition of the yearly volumes of the astronomical ephemeris; he collected and analyzed all the observations of transits of Venus available to him, in order to derive a more precise value of the sun’s parallax—really the best one of his time—and performed his duties at the university as before.

But the doubts regarding Hell’s scientific credibility, intimately connected with the public defamation of the Jesuits then in vogue, survived him by nearly a century. About 1823 Encke, in his comprehensive evaluation of the transits of Venus of 1761 and 1769, rejected Hell’s observations. Ten years later, in 1834, Karl von Littrow, by misinterpreting some rediscovered fragments of Hell’s manuscripts, believed he had found direct proofs of the alleged falsification of the observations. It was not until 1883 that Simon Newcomb fully rehabilitated Hell’s reputation after having scrutinized the manuscripts preserved in the Vienna observatory. The reliability of his verdict in favor of Hell is confirmed by the fact that the sun’s parallax is far nearer to the true figure when Hell’s observations are included with due weight, than without them.

Hell’s colleagues, pupils, and friends greatly esteemed him for both his scientific and his personal qualities. He was elected to the academies of Bologna, Copenhagen, Trondheim, Göttingen, Paris, and Stockholm. Christian VII of Denmark and George III of England offered Hell honorary pensions much higher than his salary, but he refused them.

BIBLIOGRAPHY

I. Original Works. Hell edited Ephemerides astronomicae ad meridianum Vindobonensem... for 1757–1768 and 1772–1792 (Vienna, 1756–1767, 1771–1791). A. Pilgram edited 3 vols. during his absence in 1768–1770 and F. Triesnecker edited 14 vols. after Hell’s death.

Hell’s most important papers, drawn from the appendixes to the Ephemerides, are concerned with the following problems: accurate theoretical prediction and subsequent observations of the transits of Venus of 1761 and 1769; derivation of the sun’s parallax from these observations; tables of the sun, moon, and planets, with corrections and additions by Hell and Pilgram; description of certain special observational techniques; series of current astronomical and meteorological observations; latitudes and longitudes of places in northern Europe; a theoretical explanation of the aurora borealis; and “Monumenta aere perenniora inter astra ponenda. Primum Serenissimo Regi Angliae, Georgio III, Altertum, Viro celeberrimo Friderico Wilhelmo Herschel.”

Among Hell’s numerous other works are Adjumentum memoriae manuale chronologico-genealogico-historicum (Vienna, 1750; 5th ed., enl., 1774); Elementa mathematica (Cluj, 1755); Exercitationum mathematicarum partes tres (Vienna–Cluj, 1755; 2nd ed., 1759; 3rd ed., 1760; 4th ed., 1773); Elementa algebrae (Poznan, 1760; 2nd ed., Vienna, 1762; 3rd ed., 1768; 4th ed., 1773); Introductio ad utilem usum magnetis ex calybe (Vienna, 1762), translated into German as Anleitung zum nützlichen Gebrauch der künstlichen Stahl-Magneten (Vienna, 1762); Observatio transitus Veneris ante discum solis (Copenhagen, 1770); and Beyträge zur praktischen Astronomie aus den astronomischen Ephemeriden des Herrn Abbé M. Hell, translated by L. A. Jungnitz, 4 vols. (Breslau, 1791–1794).

II. Secondary Literature. See the following, listed chronologically: F. Triesnecker, “Monitum,” in Ephemerides astronomicae ad meridianum Vindobonensem anni 1793 (Vienna, 1792), pp. 3–5; C. L. von Littrow, P. Hell’s Reise nach Wardoe (Vienna, 1835); C. von Wurzbach, “M. Hell,” in Biographisches Lexikon des Kaiserthums Österreich, VIII (1862), 262–266; Poggendorff, I (1863), col. 1055; M. A. Paintner, Historia scriptorum Societatis Jesu olim provinciae Austriacae, Hungaricae (Vienna, 1855); C. Bruhns, “Maximilian Hell,” in Allgemeine deutsche Biographie, X, 691–693; S. Newcomb, “On Hell’s Alleged Falsification of His Observations of the Transit of Venus in 1769,” in Monthly Notices of the Royal Astronomical Society, 43 (1883), 371–381; C. Sommervogel, “Hell, Maximilian,” in Bibliothèque de la Compagnie de Jésus, new ed., Bibliographie. IV (Brussels–Paris, 1893), 238–258: F. Pinzger, Hell Miksa Emlékezete, 2 vols. (Budapest, 1920–1927), with a summary in German, “Erinnerung an Maximilian Hell,” in vol. II; A. V. Nielsen, “Pater Hell og Venuspassagen 1769,” in Nordisk astronomisk tidsskrift (1957), pp. 77–97; and K. Ferrari d’Occhieppo, “Maximilian Hell und Placidus Fixlmillner,” in Österreichische Naturforscher, Ärzie und Techniker (Vienna, 1957), pp. 27–31; and “Maximilian Hell,” in Neue deutsche Biographie, VIII (1969), 473–474.

Konradin Ferrari d’Occhieppo