73
also equipped the observatory with magnetometers, thus building the first geomagnetic observatory in Italy. However, Secchi left all the meteorological instruments in
the Calandrelli Tower in order to not interrupt the continuity in the homogeneous series of meteorological data. He also installed the meteorograph there. Thus,
thanks to Secchi’s directorship, the Collegio Romano Observatory became a wellequipped astronomical, meteorological, and geomagnetic observatory (Fig. 4.5).
Secchi had clearly in mind that his observatory would be devoted to what he
called “physical astronomy,” rather than attempting the sort of detailed astrometric
work that would have required larger instruments, more staff, and work plans that
would not have fit well with the duties of the religious life. His early studies dealt
with double stars, planetary and cometary astronomy, early astronomical photography, star clusters, and nebulae. However, solar studies and the attempt to find correlations between solar features (hence, solar activity) and meteorological and/or
geomagnetic trends were probably his favorite topic (Ermolli and Ferrucci, here;
Meadows 1970: 34–43).
Spectroscopic studies were initiated by Secchi in the autumn of 1862, when he
hosted a visit from the French astronomer Jules C. Janssen (1824–1907). Janssen
brought with him a pocket spectroscope to study the telluric lines of the solar spectrum (lines that are produced by the absorption of the Earth’s atmosphere), and
Secchi had the opportunity to observe some spectra of stars. He decided to buy a
similar spectroscope and thus began his well-known spectral classification work
(Hearnshaw 2014: 36–41). Secchi’s contributions to astronomy and to other scientific disciplines are extendedly described in this volume.
Secchi was not just a scientist - he was also an advisor to the Papal State and, as
a Jesuit, a man at the service of the Pope. He dreamed of a modern Papal State with
telegraphic connections, electric railways, modern lighthouses, lightning rods, and
every innovation that could improve the life of common people. He is considered a
forerunner of public safety and civil protection; he developed a telegraphic service
of weather warning for the Papal ports, designed a fire prevention project for the
Roman basilicas, and developed a lightning rod system to be installed in the main
Roman monuments (Chinnici 2019: 85–95; Calzolari and Marsella, here).
In 1864, Secchi produced an important and successful physics treatise (Capuzzo
Dolcetta, here), Sull’Unità delle Forze Fisiche (On the Unity of Physical Forces),
which was published in many editions and translations, even into Russian. It treated
on modern theories, such as gas kinetics and atomism, which had been in circulation
but not yet found in contemporary physics textbooks. Because of this book, Secchi
was attacked by the ultraconservative Dominican and Jesuit supporters of neoThomism, who considered that some of those theories were in conflict with the
Aristotelian physics found in the writings of St. Thomas Aquinas (Chinnici 2019:
261–269). Secchi worried very much about this attack, being aware that this kind of
criticism would give support to the prejudice that Church was opposed to science.
He soon found himself in a paradoxical situation: the anticlerical and freemason
political class respected him as a scientist and attacked him as a Jesuit, while the
ultraconservative clerical class respected him as a Jesuit but attacked him as a scientist. Perhaps to have a break from these stressing controversies, in 1865, he
4 Angelo Secchi: Portrait of a “Multi-versed” Jesuit Scientist
also equipped the observatory with magnetometers, thus building the first geomagnetic observatory in Italy. However, Secchi left all the meteorological instruments in
the Calandrelli Tower in order to not interrupt the continuity in the homogeneous series of meteorological data. He also installed the meteorograph there. Thus,
thanks to Secchi’s directorship, the Collegio Romano Observatory became a wellequipped astronomical, meteorological, and geomagnetic observatory (Fig. 4.5).
Secchi had clearly in mind that his observatory would be devoted to what he
called “physical astronomy,” rather than attempting the sort of detailed astrometric
work that would have required larger instruments, more staff, and work plans that
would not have fit well with the duties of the religious life. His early studies dealt
with double stars, planetary and cometary astronomy, early astronomical photography, star clusters, and nebulae. However, solar studies and the attempt to find correlations between solar features (hence, solar activity) and meteorological and/or
geomagnetic trends were probably his favorite topic (Ermolli and Ferrucci, here;
Meadows 1970: 34–43).
Spectroscopic studies were initiated by Secchi in the autumn of 1862, when he
hosted a visit from the French astronomer Jules C. Janssen (1824–1907). Janssen
brought with him a pocket spectroscope to study the telluric lines of the solar spectrum (lines that are produced by the absorption of the Earth’s atmosphere), and
Secchi had the opportunity to observe some spectra of stars. He decided to buy a
similar spectroscope and thus began his well-known spectral classification work
(Hearnshaw 2014: 36–41). Secchi’s contributions to astronomy and to other scientific disciplines are extendedly described in this volume.
Secchi was not just a scientist - he was also an advisor to the Papal State and, as
a Jesuit, a man at the service of the Pope. He dreamed of a modern Papal State with
telegraphic connections, electric railways, modern lighthouses, lightning rods, and
every innovation that could improve the life of common people. He is considered a
forerunner of public safety and civil protection; he developed a telegraphic service
of weather warning for the Papal ports, designed a fire prevention project for the
Roman basilicas, and developed a lightning rod system to be installed in the main
Roman monuments (Chinnici 2019: 85–95; Calzolari and Marsella, here).
In 1864, Secchi produced an important and successful physics treatise (Capuzzo
Dolcetta, here), Sull’Unità delle Forze Fisiche (On the Unity of Physical Forces),
which was published in many editions and translations, even into Russian. It treated
on modern theories, such as gas kinetics and atomism, which had been in circulation
but not yet found in contemporary physics textbooks. Because of this book, Secchi
was attacked by the ultraconservative Dominican and Jesuit supporters of neoThomism, who considered that some of those theories were in conflict with the
Aristotelian physics found in the writings of St. Thomas Aquinas (Chinnici 2019:
261–269). Secchi worried very much about this attack, being aware that this kind of
criticism would give support to the prejudice that Church was opposed to science.
He soon found himself in a paradoxical situation: the anticlerical and freemason
political class respected him as a scientist and attacked him as a Jesuit, while the
ultraconservative clerical class respected him as a Jesuit but attacked him as a scientist. Perhaps to have a break from these stressing controversies, in 1865, he
4 Angelo Secchi: Portrait of a “Multi-versed” Jesuit Scientist