The Medici Collections

Over the years the Medici Family, patrons of art and science, formed a superb collection of scientific instruments. Some elegant, refined pieces from this collection are displayed in this room. For nearly two centuries the instruments were kept in the Uffizi Gallery, alongside masterpieces of ancient and modern art. Begun by the founder of the Grand Duchy of Tuscany, Cosimo I de' Medici, the collection was further enriched by his sons and successors: Francesco I, interested mainly in natural-history collections and alchemy, and Ferdinando I, who bought numerous mathematical, nautical and cosmographical instruments. Cosimo II had the honour of adding Galileo's revolutionary instruments to the collection. Later, superbly original glass thermometers blown in the Palazzo Pitti glassworks were fabricated for the Accademia del Cimento, founded by Grand Duke Ferdinando II and Prince Leopoldo de' Medici. Memorable among the later Medici rulers is Cosimo III, patron of the mathematician Vincenzo Viviani, Galileo's last disciple.

This room contains a rich array of instruments designed to measure time: sundials, nocturnals and astrolabes that showed the hour by day or by night.Without clarifying what time is, astronomy has always striven to define its units on the basis of celestial phenomena, and to develop precise timekeeping instruments.Displayed here, along with commonly used scientific objects, are highly refined instruments fabricated in the artisans' shops that began to flourish in the 16th century. In the Germanic states, for instance, the members of the Schissler family were renowned, and many of their products entered the Medicean collections. Among the Italian instrument-makers, Giovanni Battista Giusti, Stefano Buonsignori and the Della Volpaia family were outstanding. Especially important in this room are the instruments from the legacy of Viviani, Galileo's last disciple. This collection includes objects of many kinds, revealing Viviani's specific interests in the field of the astronomy.

A singular form of assimilation and updating of Ptolemy's Geography, one of the founding texts of modern geographical studies, was the ambitious project for the Guardaroba Nuova in Palazzo Vecchio, conceived by Cosimo de' Medici as a grandiose theatrum mundi. This project was then emulated by Ferdinando I in the Uffizi Gallery, with a Cosmographic Room containing representations of the Medicean domains and a great Ptolemaic model of the universe designed by the cosmographer Antonio Santucci. It is the great armillary sphere that dominates this room, surrounded by terretrial and celestial globes of the finest workmanship.In the adjacent room are four globes by the Venetian cosmographer Vincenzo Maria Coronelli. Famous for the great size of his creations, he built enormous globes, nearly four meters in diameter, for Louis XIV, King of France,.As Coronelli explained in his Epitome cosmografica published in 1693, these globes are formed of many hand-written or printed sheets of paper, called gores, glued onto a large ball made of wood and papier-mâché coated with plaster.

Having consolidated their power over Tuscany, the Medici turned their gaze toward the sea, hoping to win a place in oceanic navigation and develop trade with the East and West Indies. These ambitions favoured the development of maritime science in Tuscany, making Leghorn a major centre in the Mediterranean, equipped with arsenals, naval shipyards, nautical schools and workshops for the production of nautical instruments and geographical charts, destined mainly for the captains of the Medicean fleet, the Knights of St. Stephen. The entry of the English Admiral, Sir Robert Dudley, into the service of Ferdinando I marked the consolidation of nautical science at the Medicean court. His important collection of nautical instruments, displayed in this room, along with his imposing treatise on the art of navigation, Dell'arcano del mare (The Secrets of the Sea), published in Florence in 1646-1647, became part of the Medicean collection.

In this room, numerous instruments linked to the science of warfare and military architecture are displayed. In the Renaissance, the spread of firearms had transformed battlefields into the theatre of geometric studies. Powerful mortars had compelled modifying the geometry of fortresses. Moreover, suitable knowledge of the ratio between the weight and range of cannonballs was now required, calling for the greatest precision in measurement and computation. Men of arms were thus obliged to acquire the basic mathematical principles needed for the perfect management of military operations. The display cases at the centre of the room contain instruments designed by the military engineer Baldassare Lanci, at the service of Cosimo I de' Medici from 1557. In the last display cases are the instruments bought in Germany by Prince Mattias while fighting in the Thirty Years' War as commander of the Medicean army.

The room dedicated to the great scientist is the heart of the Museo Galileo. Here are displayed the only two surviving telescopes, among the many built by Galileo; the objective lens of the telescope through which, in January 1610, he observed the satellites of Jupiter for the first time; the military and geometric compasses he developed during his years in Padua; other instruments of his invention and educational models illustrating the crucially important results attained by Galileo in his studies on mechanics. At the centre of the room is the marble bust commissioned of the sculptor Carlo Marcellini by Cosimo III de' Medici. Some relics of Galileo, the secular saint of science, are also exhibited here: his thumb, the index finger and middle finger from his right hand, and a tooth, removed from Galileo's corpse when it was translated to the monumental tomb in Santa Croce.

In January 1610, while exploring the heavens with his telescope, Galileo discovered four small star-like objects around Jupiter. Having soon concluded that these were the planet's satellites or moons, he sought to establish their orbits and periods.The velocities of orbital motion decrease from the innermost to the outermost moon. All four display almost the same brightness. It was difficult, therefore, to work out which was which and calculate how long they took to complete their orbits around the planet.To determine the positions of the moons without having to perform complex calculations each time, Galileo developed a diagram—a sort of analog calculator—called the Jovilabe. The design shows Jupiter and the orbits of the four moons to scale. The orbits are placed in a grid of parallel vertical lines spaced at intervals equal to the radius of Jupiter.While making his telescopic observations, Galileo would estimate the apparent distance of a moon from the planet in units equal to Jupiter's radius. The intersection between the vertical line corresponding to this distance and the circle representing the moon's orbit gave its position instantly. By means of a thread, one could read the value on the marked scale drawn in the margin.However, the moons' observed positions vary with the relative positions of Jupiter and the Earth in the course of their revolutions around the Sun. For example, the timing of a moon's passage in front of Jupiter, as seen from the Earth, differs from the timing of the same phenomenon if it were observed from the Sun. The time difference depends on the Earth-Jupiter-Sun angle, known as the annual parallax.To cancel this continuously variable effect, Galileo recorded the motion of the moons relative not to the Earth, but to the Sun. To avoid complicated calculations, he developed a second diagram consisting of a representation, to scale, of the orbits of Jupiter and the Earth around the Sun. Jupiter is assumed to be immobile at the moment of the observation. The diagram features a graduated scale giving the Earth's position relative to Jupiter. The parallax value could be read instantly on another graduated scale.The two diagrams were combined into a single instrument, known as the Jovilabe. Jupiter's position at the moment of observation was computed by means of a rotating disk. A moving pointer, fixed with an arm to the instrument's plate, served to determine the Earth's position at that same moment. The arm thus represents the Earth-Jupiter link, i.e., the observer's continually changing line of sight. The parallax value for any position of the Earth relative to Jupiter could be read directly on a scale on the upper rim of the instrument.

This room contains many instruments utilized in research conducted by the members of the Accademia del Cimento. Founded in 1657 by Grand Duke Ferdinando II and Prince Leopoldo de' Medici, it was the first European society exclusively devoted to science, preceding the foundation of the Royal Society in London (1660) and the Académie Royale des Sciences in Paris (1666). Following in the footsteps of Galileo, the Cimento conducted experiments to verify some principles of natural philosophy hitherto universally accepted on the basis of Aristotle's authority. The Academy concluded its work in 1667 by publishing the Essays on natural experiments, summarizing its activity. Significant results were attained in observations of Saturn, and above all in the fields of barometry and thermometry (here we see the superb thermometers and glass instruments used by the Academy). Numerous experiments were designed to verify the possibility of creating a vacuum in nature, and observing its effects on animals and objects.

Displayed in this room are various instruments used in some of the scientific disciplines that began to develop in the second half of the 17th century. At this time meteorology was progressing rapidly, thanks to perfected instrumentation for measuring variations in thermometric, barometric and hygrometric values. The systematic use of increasingly improved microscopes led to striking achievements in the fields of biology and entomology. Francesco Redi, a pioneer in these fields of research, brilliantly combined refined strategies of experimentation with scrupulous microscopic observations. Telescopes of ever greater size and more complex optical systems were also being produced by expert instrument makers. With such progress in telescopic instrumentation, astronomical observations led to crucially important discoveries.