http://agathe.gr/democracy/practice_of_ostracism.html
Ostracism Soon after their victory over the Persians at the battle of Marathon in 490 B.C., the Athenians began the practice of ostracism, a form of election designed to curb the power of any rising tyrant ... Inscribed ΜΕΓΑΚΛΕΣ ΗΙΠΠΟΚΡΑΤΕΣ, Megakles son of Hippokrates. Aristotle reports the ostracism of Megakles son of Hippokrates, and goes on to say that "the Athenians continued for three years to ostracize the friends of the tyrants, on account of whom the law had been enacted" (Athenian Constitution 22). ... Ostrakon of Hippokrates, candidate for ostracism in the 480's B.C. ... Inscribed twice ΗΙΠΠΟΚΡΑΤΕΣ ΑΛΚΜΕΟΝΙΔΟ, Hippokrates son of Alkmeonides.