“Old Smaug is weary and asleep,” he thought. “He can’t see me and he won’t hear me. Cheer up Bilbo!” He had forgotten or had never heard about dragons’ sense of smell. It is also an awkward fact that they can keep half an eye open watching while they sleep, if they are suspicious.
Smaug certainly looked fast asleep, almost dead and dark, with scarcely a snore more than a whiff of unseen steam, when Bilbo peeped once more from the entrance. He was just about to step out on to the floor when he caught a sudden thin and piercing ray of red from under the drooping lid of Smaug’s left eye. He was only pretending to sleep! He was watching the tunnel entrance! Hurriedly Bilbo stepped back and blessed the luck of his ring. Then Smaug spoke.
“Well, thief! I smell you and I feel your air. I hear your breath.

Chapter 12 Inside Information