The Microcosm

270 Chapter 6

Chapter 6 The Microcosm

The First Machine-Tool to Cut Gears

Janello Torriani’s fortune is tied to the first planetary clock, the fourteenth century Astrarium made by Giovanni de Dondi for Gian Galeazzo Visconti, count of Virtú, and later first Duke of Milan. This clock was a possession of the Duchy of Milan, and it was kept in a tower of the castle of Pavia.1 In 1566, Bernardo Sacco of Pavia, whose sources are unknown, reported that when in 1529-1530 Charles V was in Bologna for his coronation, he received Dondi’s clock as a gift.2

1 Giuseppe Brusa, following Cardano, considers Janello’s planetary clock to be an improved copy of a planetary clock allegedly made by Zelandinus: “Cardano’s words establish beyond doubt that Torriano restored the planetarium of the Flemish maker and not that of Dondi as other less informed authors wrote afterwards. Indeed Cardano was so interested in the later clock that in 1539 he began to write about it …”. Brusa’s claims are to be taken with caution, as we shall see in this section. Brusa, “Early Mechanical Horology in Italy,” 512. It seems that just after the death of Duke Gian Galeazzo Sforza in 1494, his uncle Duke Ludovico il Moro had the clock moved to the castle of Rosate. The clock remained here for some time between November 1494 and March 1495, when the clock was on display in the castle of Pavia. In 1493, the fief of Rosate had been given to Ambrogio Varesi da Rosate, physician and controversial astrologer of Ludovico il Moro. Bedini and Maddison, Mechanical Universe, 25-37. 2 “Dominante deinde Transpadanis [not Padua like Garcia-Diego reports!] Joanne Galeacio Vicecomite, fabricatum fertur eiusmodi horologium, non solum horam, sed etiam syderum ex- pressis notis, atq; temporibus ac Solis, Lunaeque; meatibus cuius operis autor ignoratur colloca- tumque illud horologium in arce, vel castello Papiae fuit, ubi defuncto principe tam mirabile opus despectum iacuit, circulis etiam a suo loco sublatis. Exacto postea saeculo anni millesimi & qu- ingentesimi, circa annum vigesimum nonum, quo CAROLVS QVINTVS Bononiae Imperialem coro- nam suscepit, allatum eidem Imperatori illud horologium incompositum (ut erat) situ, ac rubigine foedatum, fuit quo conspecto, machinam admiratus, curari tanti operis instaurationem fabris undique evocatis iussit. Quibus circa opoficii restitutionem frustra laborantibus, unus ac- cessit Ioannes Cremonensis, cognomento Ianellus, aspectu informis, sed ingenio clarus qui tan- tum opus speculatus, refici posse machinam dixit: sed nequiequam profuturam, ferris rubigine atritis, exesisque, nisi novum instrumentum ad illius vetusti similitudinem, ac symmetriam com- ponatur. Aggressusque opus, sive priorem artificem immitando, atque aemulando, sive exaquan- do diuturno labore opificium absolvit: quod deferri in Hispaniam Imperator voluit, magistro Ianello simul deducto”: Bernardo Sacco, Bernardi Sacci Patritii Papiensis De Italicarvm Rervm Varietate Et Elegantia Libri X ; In Qvibvs Mvlta Scitv Digna Recensentur, De Populorum vetustate, dominio, & mutatione ; Item de Prouinciarum proprietate, & Ro. Ecclesiae amplificatione … (Pavia: [s.n.], 1565), 150-51. One can recognise the use of Vida from the line “aspectu informis,

At that time Francesco II Sforza was duke of Milan, and after a period of some serious tension with the Emperor, on this occasion he finally made peace with him. Unfortunately, the clock was broken and unrepairable, thus Torriani built a better version of it: the Microcosm. The antecedents of Torriani’s project to create this planetary clock are still quite mysterious: first of all, even if Sacco’s account is the most commonly accepted by historians, Silvio Leydi, with some reason, has observed that a broken and rusted clock was perhaps not an alto- gether apt ducal gift for the new Caesar.3 What we know about the genealogy of Torriani’s Microcosm is that in the winter 1547, after having been summoned, as Gulielmus Zenocarus recorded,4 Janello reached the Emperor in Ulm, arriving at court on the very day of Charles V’s birthday, something that was received as a good omen. On this occasion, Charles gave him the go-ahead, and consequently Ferrante Gonzaga (Governor of Milan since April 1546) gave the order to the treasury of the duchy to provide for the payment of Janello’s new machine.5 In the following years, a globe of rock crystal, made by Jacopo Nizzola da Trezzo, which contained a paper-globe made by the famous Flemish cosmographer Gerhard Mercator, had to be placed on the top of the clock. Janello and Jacopo Nizzola da Trezzo eventually delivered the finished Microcosm in March 1554. However, as the eyewitness Gasparo Bugato wrote, even without the crystal sphere, the Cesar’s Sky, as some people called it, was already working, and it was shown to the resident

sed ingenio clarus”; however, Vida never talked about the clock being given to Charles V as a present in 1529-30. Even the attribution to Cardano of this idea was a misconception, as we are going to see in this section. 3 Indeed, already in the previous century, the Astrarium went out of order, and it seems that nobody could fix it. Perhaps Gulielmus Zelandinus managed to repair it for a while, or even to build a new version of it. It seems that the dukes of Milan, in the years 1440, 1457 and 1488, had him moving to the court for this purpose. We have already met Zelandinus: he was a physician and constructor of astronomical instruments from the Low Countries who later emigrated to Carpentras in Province, and who worked for the crowns of France, Sicily (King René), and for the dukes of Milan. He is the author of the Liber Desideratus, a manual for the use of a planetary instrument; in the year 1494/5, the second edition of Liber Desideratus had been published in Cremona. Bedini, “Falconi,” fasc. 1, 44. 4 We have previously met the Flemish Willem Snouckaert van Schauwenburg, Charles V’s librar- ian and official biographer who had personal knowledge of Torriani. 5 Silvio Leydi has recently published a series of five tranches of payment (600 scudi in total) performed by the treasury of the duchy of Milan (April 1547-October 1548). The Microcosm cost 500 scudi, plus an extra hundred for the decorations in gold and silver. This amount of money was considerable: it was equivalent to 10-years’ wage for a master mason: Leydi, “Un cremonese del Cinquecento,” 134.