Silvio A. Bedini

The Borghesi Astronomical Clock
In the Museum of History and Technology

The history of the 18th-century Borghesi astronomical clock is described here from contemporary source material. The evolution of its design by Father Francesco Borghesi and the building of the complex mechanism devised by the clockmaker, Bartolomeo Antonio Bertolla, is a story of the vision of one man turned into reality by another. The result of their collaboration is the unique, astronomical timepiece now in the Museum of History and Technology.

The Author: Silvio A. Bedini is curator of mechanical and civil engineering in the Smithsonian Institution's Museum of History and Technology.

"... All this work I had performed eagerly, so that, while in my room, I might contemplate leisurely, both during the day and in the night, the true face of the heavens and of the seas unobscured by clouds, even though I had no astronomical equipment."[1]

With these words, Father Francesco Borghesi (1723-1802) of Mechel described the reasons which inspired him to invent a unique astronomical clock which is now in the horological collection of the Museum of History and Technology.

This complicated mechanism, which performs a multitude of functions, was designed by Father Francesco Borghesi, a secular priest in Venezia Tridentina. It was constructed in 1764 under his direction by a provincial clockmaker named Bartolomeo Antonio Bertolla (1702-1789) of Mocenigo di Rumo. It was the second of two complicated astronomical clocks which Father Borghesi designed and which Bertolla constructed. According to contemporary sources, this clock was presented to the Empress Maria Theresa of Austria soon after its completion.

Its history is rather hazy, except for the fact that in 1780 this second Borghesi timepiece was still in the Imperial Palace in Vienna. The clock was again noted in 1927 when it was sold at a public auction in New York.[2] Subsequently, it was acquired for the Smithsonian Institution.

ACKNOWLEDGMENTS

The author wishes to acknowledge the valuable assistance received from the following: Dr. Amos Avery, Amherst, Massachusetts; Mr. Edwin A. Battison, curator of light machinery and horology, U.S. National Museum; Dott. Richard Blaas, Oesterreiches Staatsarchiv, Vienna; Dott. Adolfo Cetto, librarian, Biblioteca Comunale di Trento, who made copies of Borghesi's two volumes available; Signor Mario di Mario, editor of La Clessidra, Rome, who permitted several of the illustrations in Sig. Luigi Pippa's article to be used herein; Mr. Walter A. Gilbert, Norwich, Connecticut; Dr. Heinrich Linardi, Uhrenmuseum der Stadt Wien, Vienna; Signor Luigi Pippa, Milan, Italy; Cav. Ing. Guido Ucelli di Nemi, Presidente, and Dott. Federico Morelli and Cav. Orazio Curti of the Museo Nazionale della Scienza e della Tecnica, Milan, for their cooperation on the descriptions and illustrations of the restored clockshop of Bartolomeo Antonio Bertolla; and Dr. Edward Waters, Division of Music, Library of Congress, Washington, D.C.