History of the Peloponnesian War

The tactics of Demosthenes had divided them into companies of two hundred, more or less, and made them occupy the highest points in order to paralyze the enemy by surrounding him on every side and thus leaving him without any tangible adversary, exposed to the cross-fire of their host; plied by those in his rear if he attacked in front, and by those on one flank he moved against those on the other.

In short, wherever he went he would have the assailants behind him, and these light-armed assailants, the most awkward of all; arrows, darts, stones, and slings making them formidable at a distance, and there being no means of getting at them at close quarters, as they could conquer flying, and the moment their pursuer turned they were upon him. Such was the idea that inspired Demosthenes in his conception of the descent, and presided over its execution.