http://agathe.gr/democracy/the_speakers.html
The Speakers Litigants spoke on their own behalf, although occasionally using speeches prepared by trained professionals; skillful rhetoric was necessary in order to sway a jury. The speeches written by ... Of these, perhaps the best known for his ability in forensic speaking was Demosthenes, a statesman who led Athenian opposition to the rising power of Philip of Macedon in the 4th century B.C. Demosthenes' skills as a public speaker in the assembly were honed by training and considerable self-discipline: They say that when he was still a young man he withdrew into a cave and studied there, shaving half of his head to keep himself from going out; also that he slept on a narrow bed in order to get up quickly and that since he could not pronounce the sound of R he learned to do so by hard work, and since in declaiming for practice he made an awkward movement with his shoulder, he put an end to the habit by fastening a split or, as some say, a dagger from the ceiling to make him through fear keep his shoulder motionless. ... Fragmentary waterclock (klepsydra), late 5th century B.C. H.: 0.172 m. ... Centered above the spout, just below the rim, is a hole that would permit the pot to be filled to the same level each time.