An astronomical, geographical and scientific journey through the Papal States
I came across two eighteenth century Jesuit priests who stayed briefly in Comacchio and Ferrara areas by chance. It happened a few months ago when Professor Luigi Pepe of the University of Ferrara suggested that I translate the scientific odyssey of these two researchers, who happened to be Jesuit priests, from French and Latin. This voluminous book was published in Latin in 1755 and turned into French a few years later. The Latin title is: De litteraria expeditione per pontificiam ditionem ad dimetiendos duos meridiani gradus et corrigendam mappam geographicam, iussu et auspiciis Benedicti XIV Pont. Max;. and the French: Voyage astronomique et geographique dans l'État de l'Église entrepris par l'ordre et sous les auspices du pape Benoît XIV [Astronomical and geographical journey through the Papal States, made by order of Pope Benedict XIV]. The Pope Benedict that appears in the title is the famous Prospero Lorenzo Lambertini from Poggio Renatico, who was pope from 1740 to 1758. The authors were Father Christopher Maire (1697-1767), a mathematician and mapmaker, and Father Roger Joseph Boscovich (Dubrovnik, previously Ragusa, 1711-1787), a mathematician, astronomer, geodesist, physicist and poet. Father Boscovich only had the most basic instruments to make his measurements with: a level, perch, plumb line, isochronous pendulum and sextant with telescope. The instruments, trigonemetrical calculations, geodetic polygons, and astronomical references are described in the book. The two priests travelled through the Papal States, making precise calculations of the geographical coordinates of hundreds of localities, and more especially, calculating two degrees of the Rome meridian. They worked very well together and actually complemented one other since Father Maire was more interested in geography and cartography, while Father Boscovich wanted to investigate the meridian arc (from Rome to Rimini) to try and understand the Earth's shape. Of course he knew that the Earth was round; what he really wanted to understand was whether it was a perfect sphere or a spheroid, either egg or onion-shaped. The two scientists in their soutanes passed by Comacchio and Ferrara, then on to Bologna. Part of their work involved inspection of the work being done on the canal, to be called after the pope, Cavo Benedettino. It was May 1752. Their passage on Ferrara refers to the Jesuit priest Sivieri as "the best plumber and topographer in Italy": "Father Sivieri ... was a great help to us. He had a huge collection of geographical records and had made a map based on these notes that included the Ferrara and Bologna areas as far as the mountains, and other areas around Ravenna. This map, which he dedicated to Pope Benedict XIV and presented to Cardinal Valenti, was very useful and made our task much easier". The scientific priority at the time was to measure the meridian degrees. A number of measurements were being made in France to this end, and expeditions had been sent to Ecuador and the Arctic Circle. Boscovich had hoped to carry out this type of research and had requested the Pope's patronage for this purpose. The book by Father Maire and Father Boscovich is a true scientific journey linked to an enthusiastic geographic journey in the heart of Italy. Three centuries later, it could also be considered as a journey through time.