Middle point

"A more regular system was developed in the schools of Alexandria, its invention being ascribed to Aristophanes of Byzantium (260 B.C.). This was the use of the full point with certain values in certain positions (θέσεις) : the high point (στιγμὴ τελεία), equivalent to a full stop; the point on the line (ὑποστιγμή), a shorter pause, equivalent to our semicolon; and the point in a middle position (στιγμὴ μέση), an ordinary pause, equivalent to our comma. In the Codex Alexandrinus the middle and high points are pretty generally used. But the middle point eventually disappeared; and about the ninth century the comma was introduced."