Bg 1.12

tasya sanjanayan harsam
kuru-vrddhah pitamahah
simha-nadam vinadyoccaih
sankham dadhmau pratapavan

Word for word: 
tasya — his; sanjanayan — increasing; harsam — cheerfulness; kuru-vrddhah — the grandsire of the Kuru dynasty (Bhisma); pitamahah — the grandfather; simha-nadam — roaring sound, like that of a lion; vinadya — vibrating; uccaih — very loudly; sankham — conchshell; dadhmau — blew; pratapa-van — the valiant.

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Then Bhisma, the great valiant grandsire of the Kuru dynasty, the grandfather of the fighters, blew his conchshell very loudly, making a sound like the roar of a lion, giving Duryodhana joy.

Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The grandsire of the Kuru dynasty could understand the inner meaning of the heart of his grandson Duryodhana, and out of his natural compassion for him he tried to cheer him by blowing his conchshell very loudly, befitting his position as a lion. Indirectly, by the symbolism of the conchshell, he informed his depressed grandson Duryodhana that he had no chance of victory in the battle, because the Supreme Lord Krishna was on the other side. But still, it was his duty to conduct the fight, and no pains would be spared in that connection.