Possible Clues:

• Greek mathematician agreed to be embraced by Greek god
• Ancient Greek scientist (of buoyancy principle)
• Old Greek bridges spanning one huge stretch of water
• Old Greek dares somehow to collect toll
• Greek mathematician ('Eureka')
• Ancient Greek mathematician/inventor
• Syracusan rang during a short break
• Mathematician agreed with god outside
• Old scientist agreed to cut a holiday short
• Man of principle made riches in a way