Mbh 1.135.2

“Vaisampayana said, ‘When everyone had failed, Drona smilingly called Arjuna and said unto him, ‘By thee the aim must be shot; therefore, turn thy eyes to it. Thou must let fly the arrow as soon as I give the order. Therefore, O son, stand here with bow and arrow for an instant.’ Thus addressed, Arjuna stood aiming at the bird as desired by his preceptor, with his bow bent. An instant after Drona asked him as in the case of others, ‘Seest thou, O Arjuna, the bird there, the tree, and myself?’ Arjuna replied, ‘I see the bird only, but nor the tree, or thyself.’ Then the irrepressible Drona, well-pleased with Arjuna, the instant after, again said unto that mighty car-warrior amongst the Pandavas, ‘If thou seest the vulture, then describe it to me.’ Arjuna said, I see only the head of the vulture, not its body.’ At these words of Arjuna, the hair (on Drona’s body) stood on end from delight. He then said to Partha, ‘Shoot.’ And the latter instantly let fly (his arrow) and with his sharp shaft speedily struck off the head of the vulture on the tree and brought it down to the ground. No sooner was the deed done than Drona clasped Phalguna to his bosom and thought Drupada with his friends had already been vanquished in fight.