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Riccioli, Giambattista

1. Dates
Born: Ferrara, 17 April 1598
Died: Bologna, 25 June 1671
Dateinfo: Dates Certain
Lifespan: 73
2. Father
Occupation: Unknown
No information on financial status.
3. Nationality
Birth: Italian
Career: Italian
Death: Italian
4. Education
Schooling: Religous Order, D.D.
Riccioli appears to have been educated within Jesuit schools. Hoefer says that he studied at the University of Bologna, but until I find a better source for that I am rejecting it; I am convinced that he was at the Jesuit college in Bologna. As with other such Jesuits, I assume the equivalent of a B.A. and as a full Jesuit he would have had a doctorate in theology.
5. Religion
Affiliation: Catholic
Riccioli entered the Jesuit order on 6 Oct. 1614, when he was 16. He spent his entire life in the service of the Jesuits.
6. Scientific Disciplines
Primary: Astronomy, Mechanics, Geography
Subordinate: Cartography, Optics
Committed to the Catholic Church, Riccioli was of necessity in conflict with the Copernican system, which he tried to refute even while acknowedging it as the best mathematical hypothesis.
As an observing astronomer, he traced the topography of the moon and introduced some of the nomenclature that is still used. He also investigated the libration of the moon. He described sunsports, compiled star catalogues, observed a double star, noted the colored bands parallel to Jupiter's equator, and made important observations of Saturn.
As an astronomer, he also investigated atmospheric refraction, and refraction in general.
He did experiments with falling bodies, intended to refute Galileo's arguments on the motion of the earth--i.e., Riccioli argued that they showed the earth had to be at rest. His experiments confirmed Galileo's concept of uniformly accelerated motion.
Riccioli set out to compose a geographical treatise (his Geographia et hydrographia reformata) that would embrace all the geographic knowledge of his time.
He did measurements to determine the radius of the earth and to establish the ratio of water to land.
7. Means of Support
Primary: Church Life
Riccioli taught in the Society's schools in Parma and Bologna--literature, rhetoric, philosophy, and theology.
Koyré says that he was a professor of philosophy in the University of Bologna, but I am convinced this is mistaken.
8. Patronage
Types: Eccesiastic Official, Aristrocrat, Court Official
He dedicated one part of Almagestum novum, 1651, to Card. Gerolamo Grimaldi, and another part to Honoratio II, Prince of Monaco.
He dedicated Geographiae et hydrographiae reformatae libri, 1661, to Card. Emmanuelo.
He dedicated Astronomia reformata, 1665, to Ferdinand, Duke of Bavaria.
He dedicated Vindicae kalendarii gregoriani, 1666, to Card. Gerolamo Boncompagni (I think this is the man who became Clement IX.)
He dedicated Argomento fisico-matematico, 1668, to F.C. Caprara, Conte di Pantano, Confaloniere di Giustizia of Bologna.
Leopoldo de' Medici presented Riccioli with a copy of the Accademia's Saggi.
9. Technological Involvement
Types: Instruments, Cartography
He developed a leveling device for use in surveying. He also published a work on the "geographic cross," another surveying instrument.
He developed a way to measure the diameter of the sun.
With Grimaldi he perfected the pendulum as an instrument to measure time.
Riccioli published tables of latitude and longitude for a great number of localities, correcting previous data. He also published Geographiae et hydrographiae reformatae libri duodecim.
10. Scientific Societies
Memberships: None
  1. A. Koyré, "An Experiment in Measurement," Proceedings of the American Philosophical Society, 97 (1953), 222-37.
  2. P. Galluzzi, "Galileo contra Copernico: Il dibattito sulla prova 'galileiana' di G.B. Riccioli contro il moto della terra alla luce di nuovi documenti," Annali dell'Istituto e museo di storia della scienza di Firenze, 2.2 (1977), 87-148.
  3. Hoefer, Nouvelle biographie générale, (Paris, 1857-66), 42, 147- 9.
  4. G. Tiraboschi, Storia della letteratura italiana, 9 vols., new ed. (Firenze, 1793), 8, 226-7.
  5. P. Riccardi, Biblioteca matematica italiana, 1, 370-4.
  6. Edmond R. Kiely, Surveying Instruments, (New York, 1947), p. 132.
  7. Carlos Sommervogel, ed. Bibliothèque de la Compagnie de Jésus, (Brussels, 1891), 6, cols. 1796-1805.
  8. Robert McKeon, "Les débuts de l'astronomie de precision," Physis, 13 (1971), 225-88; 14 (1972), 221-42; especially 13, 234.
  9. A. Fabroni, Vitae italiorum doctrina excellentium, (Pisa, 1778), 2, 355-78.
  10. Luigi Ughi, Dizionario storico degli uomini illustri ferraresi, (Ferrara, 1804), 2, 129-30.
  11. Lorenzo Barrotti, Memorie istoriche di letterati ferraresi, (Ferrara, 1793), 2, 270-7.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

Note: the creators of the Galileo Project and this catalogue cannot answer email on geneological questions.

©1995 Al Van Helden
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