Page - 119 - in Maximilian Hell (1720–92) - And the Ends of Jesuit Science in Enlightenment Europe

119Enlightened and Jesuit Networks, and a New Node of Science purchased in Vienna on his way back from Leiden, others obtained later on via a Buda merchant, and ones constructed by himself. In 1757, as a supplement to his noteworthy “introduction to the principles of a more solid philosophy,”76 he published his (very accurate) calculation of the geographic latitude of Debre- cen. This is all the more noteworthy as—though in Leiden, Hatvani obtained some experience in astronomy and took part in the observation of the lunar eclipse of July 25, 1748—Debrecen itself, like any other Protestant school in the country, was not equipped with an observatory. Two years after his work on the latitude of his town, the professor at the re- formed college contacted the Jesuit imperial astronomer. Hatvani had read in the Latin-language newspaper Diarium Viennense (Viennese diary) that Hell and his counterpart at the Jesuit observatory, Joseph Liesganig (1719–99), had recently observed Halley’s Comet in the company of Emperor Francis I. Hat- vani now wrote to inform the court astronomer that on the very same day as you observed it [i.e., the comet] in the presence of His Highness the Emperor, on the 3rd of May, I too caught sight of it with my naked eye. At 9 o’clock of the same evening I showed it to our students, and at about the same time on the following evening I demon- strated it to the highly illustrious Judge of this city.77 Hatvani then proceeds to give the details of his observations, for which he used an eleven-foot telescope that Johann Friedrich Weidler (1691–1755)—a profes- sor of mathematics and law at the Protestant University in Wittenberg, also famous for his Historia astronomiae (History of astronomy [1741])—had once provided for him. He adds: I am writing this to you, elevated Gentleman, for no other reason than that you shall become aware that we who live in the flatlands are not idle observers of Urania either. I beg you to forgive me, a person whom you do not know even by name, for my daring to intrude in your arduous affairs. However, it is that common bond that unites all disciplines in a sort of blood relationship, which has brought me, a man occupying the lowlands 76 István Hatvani, Introductio ad principia philosophiae solidioris cui accedit observatio eleva- tionis poli Debrecinensis (Debrecen: Kállai, 1757), published in Hungarian as Bevezetés a szilárdabb filozófia alapelveibe (Debrecen: Debreceni Akadémiai Bizottság, 1990). 77 Hatvani to Hell in Vienna, dated Debrecen, May 29, 1759, wus, secretary’s copy.