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 was heard by the anti-submarine warfare trawler HMS "Moonstone" who fired a warning signal. At around 16:30, while the submarine was still on the surface, she was attacked by an enemy plane. "Galileo Galilei" was forced to submerge but remained on station considering a rather weak response to her sighting. When the darkness fell, the boat resurfaced to recharge the batteries, but it was discovered by the British ship forcing the submarine to crash dive and go through a brief but intense depth-charge attack which did not cause any damage. In the morning of June 19, while "Galileo Galilei" was