Thus he gave instructions to all the princes in the (science of) arms. To keep them away for long, he gave them Kamandala (a vessel narrow mouth) for fetching water. But he gave his son a Kumbha (wide mounted vessel to fetch water), so that it may not take him, long (to fill it). When they were thus kept away, Drona instructed his son some superior methods of using arms. Arjuna came to know it.