An experiment in the Accademia del Cimento
An experiment in the Accademia del Cimento
Image 1. ‘Esperimento all'Accademia del Cimento’, a fresco by Martellini Gaspero (1785-1857) painted in 1841 in Romantic style, within a lunette in the Tribuna di Galileo in Florence. Source: Storia di Firenze.
Image 2. Palazzo Pitti, garden facade (ascribed to Brunelleschi) facing the anfiteatro of the Boboli Garden. Photo by Stefan Bauer, 13 September 2004. Source: Wikimedia. Licence: CC BY-SA 2.5.
Image 3. Boboli Garden seen from Palazzo Pitti. Photo by Ricardo André Frantz, 2006. Source: Wikimedia. Licence: CC BY-SA 2.5.
Image 4. Palazzo Pitti and Biboli Garden, c. 1599. Lunette in the Museo di Firenze com’era. Public domain. Source: Wikimedia. Licence: public domain.
Image 5. Boboli Gardens in the 18th century. Source: Wikimedia. Licence: public domain. The palace is in the bottom left, and the amphitheatre in the top left.
Description. Image 1 depicts one of the most famous experiments conducted by the Accademia, which was designed to test whether cold was transmitted by rays which could be reflected and concentrated by a concave lens in the same manner as the rays of the sun. The experiment is described in section VII.9 of the Saggi (p. clxxvi; Essayes, p. 103) as follows:
Of Reflected Cold. We were willing to try [sperimentare], if a Concave Glass set before a mass of 500 l. of Ice made any sensible repercussion of Cold upon a very nice Thermometer of 400 deg. placed in its Focus. The truth is, it immediately began to subside, but by reason of the nearness of the Ice, ‘twas doubtful, whether the direct, or reflected rays of Cold were more Efficacious: upon this account, we thought of covering the glass, and (whatever may be the cause) the Spirit of Wine did indeed presently begin to rise; for all this we dare not be positive; but there might be some other cause thereof, beside the want of the reflection from the Glass; since we were deficient in making all the Trials [reprove] necessary to clear the Experiment [esperienza].
Resources. In 1843, Vincenzo Antinori produced a Guida per la Tribuna di Galileo which described all the paintings and sculptures which it contained. A video produced by the Museo Galileo uses this text to analyse the depiction of this famous experiment within the painting of 1841. A similar analysis in still images is provided by Internet culturale.
Commentary. A noteworthy feature of the text above is the caution of the academicians in deriving principles from an inconclusive experiment. The finely graduated tall themometer is crucial to the experiment: the point of a thememometer divided into 400 degrees is not that it was capable of measuring a huge range of temperatures but that it could measure tiny changes within a narrow temperature range.
The most striking feature of the painting is the central presence of the co-founder of the academy, the Grand Duke of Tuscany, Ferdinando II de' Medici (1610-1670). This reflects the eagerness of the patron of the Tribuna, Grand Duke Leopoldo II (1797-1870), of the recently established ruling House of Lorraine-Habsburg, to associate his dynasty with the scientific prestige of this past era. Yet the active engagement of Ferdinando and his younger brother Leopoldo is a strikingly distinctive feature of the Cimento, which links it to prince-practitioners in Kassel and Prague of the earlier era: the academy even met within their Florentine residence, the Palazzo Pitti and its magnificent gardens (images 2-5). This active involvement of the prince himself offered great advantages and also significant constraints on the activities of the Accademia. Appreciating this balance is crucial to understanding the strengths and weaknesses of the Cimento as a whole.
Credits: Howard Hotson (November 2016)