Cieli Medicei - Divini and Campani

Portrait of Eustachio Divini
(1610 -1685)

The first prize in telescope making remained, however, in Italy. First it passed from Florence to Naples with Francesco Fontana (c. 1590-1656), and then from Naples to Rome. There the expert in optics Eustachio Divini (1610-1685) gained international fame until Giuseppe Campani (1635-1715) tried to wrestle it from him.
The rivalry between Divini and Campani turned into a contest involving the Florentine Accademia del Cimento (1657-1667). To decide which of the contenders should be named the greatest optical expert, Prince Leopoldo de' Medici (1617-1675) asked his academicians to direct the controversy with specially designed experiments. The members set out to evaluate the quality of Divini's and Campani's telescopes by reading texts at a distance.
Despite the undeniable merits of Divini's telescopes (the academicians made out Saturn's shadow cast on its ring with one of these instruments in 1660), it was Campani's telescopes that won the day. Gian Domenico Cassini (1625-1712), from Bologna, used Campani's telescopes with great success to make a series of new celestial discoveries when he was called to Paris to direct the Observatory there.

Related objects
	Inv. 2553 V.29 Octagonal telescope 1664 Eustachio Divini, Rome Wood, cardboard, Florentine paper Length 2980 mm
	Inv. 2557 V.54 Octagonal telescope 1674 Eustachio Divini, Rome Wood, cardboard, Florentine paper Length 5650 mm
	Inv. 2551 V.24 Terrestrial telescope c. 1664 Giuseppe Campani, Rome Cardboard, leather Length 2250 mm
	Inv. 2552 V.27 Terrestrial telescope 1660-1670 Eustachio Divini Cardboard, paper Length circa mm 3800
	Inv. 3185 V.51 Terrestrial telescope 1665 Giuseppe Campani Wood, cardboard, leather Length circa 12000 mm
	Inv. 2556 V.52 Terrestrial telescope 1666 Giuseppe Campani, Rome Wood, leather Length 3430 mm
	Inv. 2560 V.53 Terrestrial telescope End of the seventeenth century Unsigned, Italian construction Cardboard, leather Length circa 4400 mm
	Inv. 2555 V.56 Terrestrial telescope c. 1665 [Attr.] Eustachio Divini or Jacopo Mariani Wood, cardboard, leather Length circa 8800 mm
	Inv. 2587 V.6 Objective lens 1665 Giuseppe Campani, Rome Glass Diameter 137 mm
	Inv. 2573 V.8 Eyepiece lens 1665 Eustachio Divini, Rome Glass, cardboard, Florentine paper Length 46 mm, diameter 55 mm
	Inv. 2574 V.9 Eyepiece lens 1666 Eustachio Divini, Rome Glass, cardboard, Florentine paper Length 107 mm, diameter 63 mm
	Inv. 3449.2 V.7 Tube for composite eyepiece 1665 Unsigned Cardboard, Florentine paper Length 280 mm, diameter 72 mm