137
© Springer Nature Switzerland AG 2021
I. Chinnici, G. Consolmagno (eds.), Angelo Secchi and Nineteenth Century Science,
Historical & Cultural Astronomy, https://doi.org/10.1007/978-3-030-58384-2_8
Chapter 8
Angelo Secchi, Instrument Innovator
Kevin L. Johnson
8.1 Introduction
In contrast to modern scientists who work within a narrow field of study, Angelo
Secchi was interested in the entire range of the physical sciences along with many
aspects of the emerging electrical technologies, especially telegraphy. He was
involved with and studied geodesy, meteorology and oceanography along with the
disciplines of astronomy and physics already outlined. His contributions to a wide
range of subjects involved both theoretical research, though to a lesser extent
(Chinnici 2019), and practical observation (Mazzotti 2010: 63–4).
From the examination of surviving instruments used by Secchi, along with his
writings—both books and papers—one can assess the way he used instruments,
including his innovations in devising new instruments, or modifying them for more
effective measurement and easier use. Here we will examine the instruments used
by Secchi in astronomy, physics, meteorology and oceanography. In particular, we
will concentrate on his stellar spectroscopes which included direct-vision, compound, object prism and grating types of instruments used for astronomy; Secchi’s
thermoheliometer (an early form of actinometer); his highly complex universal
meteorograph; and the Secchi disc used in oceanography to measure water
transparency.
K. L. Johnson (*)
Society for the History of Astronomy, Birmingham, UK
© Springer Nature Switzerland AG 2021
I. Chinnici, G. Consolmagno (eds.), Angelo Secchi and Nineteenth Century Science,
Historical & Cultural Astronomy, https://doi.org/10.1007/978-3-030-58384-2_8
Chapter 8
Angelo Secchi, Instrument Innovator
Kevin L. Johnson
8.1 Introduction
In contrast to modern scientists who work within a narrow field of study, Angelo
Secchi was interested in the entire range of the physical sciences along with many
aspects of the emerging electrical technologies, especially telegraphy. He was
involved with and studied geodesy, meteorology and oceanography along with the
disciplines of astronomy and physics already outlined. His contributions to a wide
range of subjects involved both theoretical research, though to a lesser extent
(Chinnici 2019), and practical observation (Mazzotti 2010: 63–4).
From the examination of surviving instruments used by Secchi, along with his
writings—both books and papers—one can assess the way he used instruments,
including his innovations in devising new instruments, or modifying them for more
effective measurement and easier use. Here we will examine the instruments used
by Secchi in astronomy, physics, meteorology and oceanography. In particular, we
will concentrate on his stellar spectroscopes which included direct-vision, compound, object prism and grating types of instruments used for astronomy; Secchi’s
thermoheliometer (an early form of actinometer); his highly complex universal
meteorograph; and the Secchi disc used in oceanography to measure water
transparency.
K. L. Johnson (*)
Society for the History of Astronomy, Birmingham, UK