1925-2025: One Hundred Years of the History of Science in Florence

Leonardo Ximenes (1716-1786)
Florence, 1757
Florence, Biblioteca del Museo Galileo, MED 1809

The Florence Cathedral houses a great camera obscura meridian. A gnomonic hole dating to 1475 is found at the base of the lantern of the dome. On the summer solstice, June 21, solar rays passing through the gnomon illuminate a marble disk inlaid on the pavement of the Cappella della Croce. In 1755, the astronomer Ximenes added to the church’s pavement a line marking the hours in correspondence to the local meridian, thus allowing for the possibility of new and more complex astronomical measurements. The plate illustrates, in plan and section, the path of the sun rays at noon on the summer solstice.

Giovanni Oliva (16th-17th centuries)
Livorno or Marseille, 1616.
Florence, Biblioteca del Museo Galileo, MED GF 028

To protect their economic interests throughout the Mediterranean, and wishing to embark on oceanic navigation, the Medici transformed Livorno into one of the most important Mediterranean ports. They also created a workshop intended for the production of scientific instruments and portolans, including maps for collectors. Drawn and colored by hand, these finely decorated maps were destined for princes and potentates, scholars and connoisseurs. In the plate, Central and Southern America with the Amazon River.

Domenico Fontana (1543-1607)
Rome, 1590
Florence, Biblioteca del Museo Galileo, MED GF 018

The framework used to move the Vatican Obelisk in St Peter’s Square in Rome. The competition for proposals as to how to move the Egyptian obelisk from its placement at the left of St. Peter’s to a position in front of the basilica’s façade took place in 1585 and was won by Domenico Fontana. More than three meters high and weighing 300 tonnes, the obelisk was shifted in 1591 thanks to 900 people, 140 horses, and a veritable forest of winches.

Erone Alessandrino (1st century)
Bologna, 1647
Florence, Biblioteca del Museo Galileo, MED 0764/03

Second Italian edition of Heron’s Pneumatica, translated by the architect Giovanni Battista Aleotti (1546-1636). This richly illustrated work explains how to create spectacular water effects and self-propelled apparatuses using energy produced by air, water, and steam. The book stimulated an interest in pneumatics that grew over the course of the 16th century, leading to experiments focused on creating a vacuum.

Reconstruction
Concept: Giovanni Di Pasquale
Construction: Opera Laboratori

The reconstruction shows the operation of one of the most spectacular apparatuses of ancient pneumatics, described in Heron’s Pneumatica. The device consists of a platform on which is placed a branch with some fake birds. Through a series of small tubes, the water forces air into the duct that runs through the branch until it reaches the body of one of the birds and the whistle hidden in its beak, generating the chirp.

Galileo Galilei (1564-1642)
Florence, 1632
Florence, Biblioteca del Museo Galileo, MED 1026/02

The book is written as a dialogue between three characters, Simplicio, Giovanni Sagredo, and Filippo Salviati. Although the Dialogo initially obtained the Catholic Church’s imprimatur, it resulted in Galileo’s trial on charges of heresy for having justified the Copernican system. In October 1632, the Tribunal of the Holy Office summoned Galileo to Rome and at the end of the trial issued a condemnatory sentence. The Tuscan scientist was forced to abjure and the Dialogo was included in the Index of Forbidden Books. The frontispiece depicts an imaginary dialogue between Aristotle, Ptolemy and Copernicus.