Built by Grand Duke Leopold II, the Tribuna di Galileo was opened for the Third Congress of Italian Scientists held in Florence in September 1841. Designed by the architect Giuseppe Martelli inside the Museo di Fisica e Storia Naturale, it is decorated with frescoes and bas-reliefs representing the instruments, discoveries, and historical figures that marked the advancement of experimental science. At the center of the Tribuna stands Galileo's statue, and to its right, in a niche, were originally exhibited the proportional compasses, an armed magnet, and the middle finger of the right hand of the Pisan scientist. On its left were displayed two Galilean telescopes and the objective lens with which Galileo discovered Jupiter's moons. Behind the statue today there are still the busts of his disciples: Benedetto Castelli, Bonaventura Cavalieri, Evangelista Torricelli, and Vincenzo Viviani. The Renaissance instruments and those used by the members of the Accademia del Cimento were housed in specially designed cases. In the adjoining rooms was the Museum of Ancient Instruments.