The birth of the Modena Observatory (Specola) and the direction of Giuseppe Bianchi (1826-1859)
From Astronomic Observatory to Meteorological Observatory. The Direction of Domenico Ragona
The birth of the Modena Observatory (Specola) and the direction of Giuseppe Bianchi (1826-1859)
After the Restoration, Modena became the capital of the Este Dukedom under the sovereignty of archduke Francesco IV of Austria Este again. Following the tradition of his predecessors, and with the considerable support of the brother Massimiliano, Fracesco IV manifested his interest not only in arts, increasing the already rich Este collections, but also in science, promoting the development of university museums of Modena.
The idea to provide Modena with an astronomic observatory (Specola) was conceived from archduke Massimiliano, who in 1814 entered into contact with a young from Modena, Giuseppe Bianchi, an able scientist graduated a short time before at the Mathematics-Physics Faculty.
Thanks to Massimiliano intervention, Francesco IV awarded Bianchi with a bursary which permitted him to go to Milan to complete his astronomic studies by the Brera Astronomic Observatory. In 1818, the marquis Luigi Rangoni, magister at Studies of Modena, in accord with the rector of the University Paolo Ruffini appointed him the Theoretic Astronomy chair, chair created for this purpose, and gave him the charge of Director of the Observatory, which would have been built also in Modena. Already in Janaury, Bianchi sent from Milan to Rangoni a list of the instruments to buy as fundamental to establish an Observatory: a transit instrument for right ascensions, a meridian circle, an achromatic telescope and an equatorial telescope for the extra-meridian observations.
On advice of Bianchi, Rangoni commissioned the meridian circle to the optician Georg von Reichenbach in Munich, which was delivered in Modena in 1823, and to Giovan Battista Amici from Modena (expert optician and scientific instruments builder) the other three instruments.
The “G.B. Amici’s room”, the big exposition room overlooking Piazza Roma, in a picture dated 1987: in foreground the telescopes built by the optician from Modena to whom the room is titled. In the center, the telescope of Fraunhofer (1815). Links, a bronze bust donated by the relatives in memory of Pietro Tacchini (f. L. L.) can be glimpsed.
In particular, in order to have a reflecting telescope for the observatory, Rangoni asked the rector Ruffini to contact Amici to let him giving the telescope that Amici had already built for the Reggio Emilia Gymnasium basing on an agreement that he signed in 1811 with the Kingdom of Italy to provide telescopes to Italian gymnasiums. In 1820, Amici after having signed the agreement for the construction of other two instruments, delivered the requested telescope.
6 years later however, at the expiration of the agreement for the delivery of the other two instruments, a seat for the Observatory was still missing. The Palace of the University, in the fact, didn’t have any adequate room to hold the new instrumentation.
The problem was solved thanks to Francesco IV, who with the help of the brother Massimiliano, at the beginning of the year later, on the 15th of January 1826, with a formal written document gave the Eastern Tower of his seventeenth-century Ducal Palace, placed on the rights of the façade. A plaque dictated by the Ducal librarian and archeologist Celestino Cavedoni, still present in the room on the first floor of the Observatory, remembers these events.
The works of the Observatory, directed by Gusmano Soli, Inspector of Ducal Buildings, started during the summer of the year 1826 and ended in August 1827. In order to make the room suitable for the new usage, the internal structure of the upper part of the tower (30 meters high from the ground) had to be completely transformed, without making changes to the external architectonic structure, symmetrical with the other portion of the Ducal Palace. To ensure the needed steadiness to the structure of the Observatory, a high arch of vault between the external eastern and western walls was erected. The walls were linked each other with chains to create in the tower a support for the holding of three instruments built by Amici; on the buttress walls over the vault were placed on two sides the meridian circle by Reichenbach and the transit instrument (these instruments still maintain this original position) and on the top of the arch was placed the pillar of the equatorial telescope, unfortunately nowadays lost. Also the entire roof of the tower had to be built again, because it had to be obliquely divided towards North-South direction in correspondence with meridian circle and transit instrument located on the second floor of the tower. On the first floor there were a big office or study and two smaller rooms. To reach them Soli built a staircase.
The first official observation started on the 17th of the October, as testified by Bianchi in the first volume of “Act of the Royal Astronomic Observatory of Modena” published started from 1834. On the title page of the volume the tasks of Bianchi are clearly listed “tutor of LL. AA. RR. The archdukes sons in mathematics-physical science, director of the Observatory (Specola), Cosmography professor at the University of Study, one of the Fourty of the Italian Society of Science”.
There weren’t any opening ceremonies for the new Observatory; on a local paper “The Modena Messenger” dated 7 November 1827 (n. 89) together with the news of a lunar eclipse occurred 4 days before, the construction of the Observatory, promoted by Francesco IV and placed on the eastern tower of his Ducal Palace, was remembered and also three important instruments were mentioned.
Thanks to Bianchi the Modena Observatory became a relevant seat of studies and research activities, as reported by the numerous letters preserved in the Este University Library (Venturi, 1997): thanks to him, there was the start of the daily “Meteoric Observations”, noted on registers still conserved in the Observatory, which report the meteorological events (rain or snow), the temperature (originally measured with old temperature scale but after few years measured in Celsius degrees), the atmospheric pressure, the wind and solar irradiations. Among the used instruments we still find in the collection the Bianchi pluviometer (
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The interest of the Archduke Francesco IV in the Observatory and in the astronomic studies is proved from the fact that he considered it as representation place for its relevant cultural interest and inserted it, together with the Drawings Gallery and the Library, in the visiting tours organized for princes, kings and illustrious guests creating a significant union between arts and science.
In the meanwhile, in 1850, the Metrology room was held in some rooms next to the Observatory, there were placed the archetypes of measurement instruments created for Modena Dukedom.
Following the removing of Francesco V from Modena, starting from the 1st of October 1859 pro-dukedom legitimist Bianchi was dismissed from the direction of the Observatory even thou in the years later he didn’t leave the astronomy studies. The charge of director of the Observatory was given to a promising young engineer from Modena, Pietro Tacchini, who studied at the Padua Observatory under the guide of the director Giovanni Santini.
From Astronomic Observatory to Meteorological Observatory. The direction of Domenico Ragona
After the short direction of Pietro Tacchini, who over the astronomy studies did, more in particular, meteorological observations, in 1863, the Observatory direction went to Domenico Ragona from Modena, who hold this title until 1892. Domenico Ragona was a big supporter of meteorological studies and a prolific maker of important memories in the different fields of meteorological studies. He equipped the Observatory with relevant meteorological instrumentations also thanks to the support of Cantoni, official scientific consultant of the First Meteorological Service founded in Italy in 1865, following the initiative of Agriculture Minister (Statistics Direction).
The back of the right tower of Ducal Palace in a picture dated 1898 with the hold zinced iron cupola and meteorological terrace / The balcony as appear today, still in the same position / Scheme of meteorological balcony as it was wanted by the Central Office of Meteorology directed by Pietro Tacchini.
In 1865 he projected and built the first meteorological window, improving and making the thermometric measurements possible, which till that moment were done on the terrace without any shield.
He realized two very important instruments for precision and cleverness, a hourly pluviometer in 1876 able to load water in different sections of the big barrel divided in 24 compartments thanks to a clock mechanism with discrete clicks, and an evaporimeter around 1870.
In 1876 a Royal decree dated 12 of March signed by the Minister Ruggero Bonghi on Tacchini proposal, reorganized the State Observatories in three categories: in the first one there were the Observatories of Naples, Milan, Palermo and Florence dedicated to research; in the second one there were the University Observatories of Padua, Rome (Capitol) and Turin. The one of Modena was included among the meteorological observatories together with the ones of Bologna and Parma.
Meteorograph used by the Observatory during Ragona Direction / Meteorological window projected and built by Ragona equipped with mechanisms to knock the instruments over so to read them in order to avoid to alter the measurements / Detail of hourly pluviometer by Ragona
From Meteorological Observatory to Geophysical Observatory under the direction of physicists Chistoni and Bonacini
After the death of Ragona in 1892, Ciro Chistoni, Physics professor, became the new director of the Observatory; following the suggestions of Pietro Tacchini, director of Central Meteorological Institute of Rome, he renovated the meteorological window with a meteorological balcony located at the same height and with the same orientation of the previous one, but wider and more windy, where he started to make meteorological measurements since 1898. In 1895 he published the first edition of “Publications of the Observatory” and in 1896 gave instructions for the construction of an astronomic copper cupola on the top of the tower of the observatory, only recently replaced. The hygrometer by Chistoni comes back to this period, today still present in the Observatory.
In 1897 he assigned to the Observatory the name of Geophysics, showing how the institute had increased its action field.
Among 1891 and 1898 Chistoni, thanks to the collaboration of Giacomo De Vecchi, started and concluded a long experimental study on permanent magnets; the results of his researches were spread in the publications of the Observatory.
In 1906, when Chistoni was engaged with the direction of the Institute of Terrestrial Physics of the Naples university, the charge of director of Geophysical Observatory was temporarily entrusted to Dante Pantanelli passing then, at the begin of November of the same year, to Carlo Bonacini, who addressed his researches to different directions over the astronomy, meteorology and geophysics; in 1927 thanks to him there was the promotion of the Celebration of the first centenary of the foundation of the Observatory.
Starting from the last century, the Observatory is part of the udometric National network: the meteorological observations are daily performed with the use of automatic instruments.
