HEMERODROMI were also a sort of couriers amongst the ancients, who only travelled one day, and then delivered their packets or dispatches to a fresh man, who ran his day, and so on to the end of the journey. The Greeks had couriers of this kind, whom they derived from the Persians, as appears from Herodotus. Augustus also established couriers, who, if they did not relieve each other from day to day, yet did it from space to space, and that space was not very great.