Galileo Galilei to the biography by Vincenzo Viviani) that these began by watching the swings of the bronze chandelier in the cathedral of Pisa, using his pulse as a timer. Later experiments are described in his "Two New Sciences". Galileo claimed that a simple pendulum is isochronous, i.e. that its swings always take the same amount of time, independently of the amplitude. In fact, this is only approximately true, as was discovered by Christiaan Huygens. Galileo also found that the square of the period varies directly with the length of the pendulum. Galileo's son, Vincenzo, sketched a clock based on his father's
Italian submarine Galileo Galilei and ("General Sanjurjo II"). All four were based at Soller. "Galileo Galilei" conducted several patrols without any success. In February 1938 she returned home, as Italy withdrew their submarines from Spanish service due to international pressure. Upon her return, "Galileo Galilei" was temporarily assigned to the 44th Squadron of the VII Submarine Group based at Taranto, together with "Galileo Ferraris", and the more modern , , , and . During 1939 "Galileo Galilei" and "Galileo Ferraris" were moved to a different location and the 44th Squadron was renamed to 41st Squadron. In March 1940, "Galileo Galilei" together with "Galileo Ferraris"