In ancient times, the the Minute was divided into 18 Helek, and the Second was not used until much later, perhaps the 16th Century. The Helek was 3.333 recurring of today’s seconds – which is the time it takes the Earth to rotate 1/72nd of a degree. One beat per Helek corresponds to 0.3 vibrations-per-second - also known as Hertz (Hz)