How do the snakes respond to the snake charmer's music?

The snake seems to dance to the music of the snake charmer but the fact is that a snake is 
actually deaf. It is very sensitive to vibrations. When snake charmer plays music, he also thumps the ground and the basket in which the snake is kept. The snake responds to the vibrations produced by thumping and comes out of the basket. As the snake charmer moves to and fro. The snake also moves so to keep its eyes fixed on the charmer. An on looker thinks
that the snake is actually dancing too the tune of the snake charmer.