Book excerpt: ASCLEPIODOTUS, philosopher and pupil of the Stoic Posidonius, wrote a rather dry but ordered work on Tactics as if a subject of the lecture-room, based not on personal experience but on earlier manuals. His main subjects were the branches of a military force; infantry; cavalry; chariots; elephants; arms ; manoeuvres; military evolutions; marching formation. The work ends with words of command. He wrote also a work on natural phenomena.