mathematician and cardinal (1619-1682). 4 autograph letters signed. Rome. 4to (ca. 200 x 275 mm), 6 pp., partly on bifolia (with watermark Briquet 12250), plus 1 p. with the salutation torn off (ca. 200 x 165 mm).
$ 21,723 / 18.500 €
(99240/BN65424)
A fascinating set of four autograph letters by the Italian scientist and cleric Michelangelo Ricci, who played an important role in the development of the Galilean school, very probably all addressed to Galileo Galilei's disciple Carlo Roberto Dati (1619-76). Ricci studied law and theology in Rome, and mathematics with Galileo's confidant Benedetto Castelli (ca. 1577-1643), together with the physicist and mathematician Evangelista Torricelli (1608-47), inventor of the barometer. While he could not be ordained a priest due to his epilepsy, in 1681 he was created cardinal directly by Pope Innocent XI, and occupied a place of great influence in the Vatican.
- Many of Ricci's mathematical contributions were printed in his "Geometrica exercitatio" (Rome, 1666, later retitled "Exercitatio geometrica de maximis et minimis" and reprinted in London and elsewhere), but several others are contained in his scholarly correspondence (cf. DSB XI, 404). The four letters in this collection are numbered 48-51 in chronological order, in an early hand. They are as follows: - (1) Dated 14 February 1661, a two-page letter thematically similar to the one Ricci wrote to the scholar and collector, later also cardinal, Leopoldo de' Medici on 14 March (Biblioteca Nazionale Centrale di Firenze, Gal. 276, ff. 101r-102r). It discusses the commentary and translation by Giovanni Alfonso Borelli (1608-79) of books V-VII of the "Conica" by Apollonios of Perga, long considered lost in the Western European world. While Borelli led the work, the publication, which appeared in Florence in the summer of 1661, was a collective effort by Florentine and Roman scholars. Ricci contributed greatly by researching Greek and Arabic manuscripts in the main libraries of Rome, together with a Leone Alazio (perhaps a librarian) and Abraham Ecchellensis (Ibrahim al-Haqilani), a Christian Lebanese scholar and man of letters whom Ricci himself had suggested as the translator of the "Conica", which had survived in Arabic (cf. Tripepi). Both men are mentioned in the present letter, as are Lorenzo Magalotti, Marin Mersenne and François Viète. Interestingly, Ricci mentions a copy, which Mersenne apparently borrowed from a library and then lost, of Viète's "Ad harmonicon coeleste", a text composed for his disciple Catherine de Parthenay, but never published. - (2) In this single-page letter, dated 27 February 1662, Ricci acknowledges the receipt of a poem written by the addressee, which reached him through the philosopher Lorenzo Magalotti, and of "i fogli che mancano al libro mio dell'Appolonio, et un esemplare delle belliss(i)me Pr(ose[?]) firentine da Lei pubblicate", delivered by a Sig. Falconieri. The mention of the "Prose fiorentine", published in 1661 by Carlo Roberto Dati, reveals the probable recipient of this letter, and very likely of the other three. - (3) A somewhat longer letter, dated 24 July 1662 (2¼ pp. on bifolium), discusses in detail and with some sentiment the alleged plagiarism that Ricci's teacher Torricelli is said to have committed in 1646, to the detriment of Gilles Personne de Roberval ("Robervallio", 1602-75), with respect to the quadrature of the cycloid (cf. Dhombres), and mentions other scholars swept into the dispute, such as Raffaello (?) Magiotti and Marin Mersenne. - (4) The fourth and last letter, dated 7 August 1662 (2 pp. on bifolium), dwells, among other topics, on a geometrical problem that Torricelli had raised in a letter to Ricci in 1644. After the announcement of a forthcoming trip to Germany, the letter ends with a mention of Candido del Buono and the Archbishop of Florence, who read the "Orazioni Toscane" written by the addressee - very likely the first book ("Orazioni") of Dati's "Prose fiorentine"..