It was hard to believe there was a ceiling there at all, and that the Great Hall didn't simply open on to the heavens.

Harry quickly looked down again as Professor McGonagall silently placed a four-legged stool in front of the first years. On top of the stool she
put a pointed wizard's hat. This hat was patched and frayed and
extremely dirty. Aunt Petunia wouldn't have let it in the house.

Maybe they had to try and get a rabbit out of it, Harry thought wildly, that seemed the sort of thing -- noticing that everyone in the hall was now staring at the hat, he stared at it, too. For a few seconds, there
was complete silence. Then the hat twitched. A rip near the brim opened wide like a mouth -- and the hat began to sing:

"Oh, you may not think I'm pretty, But don't judge on what you see, I'll eat myself if you can find
A smarter hat than me.

You can keep your bowlers black, Your top hats sleek and tall,
For I'm the Hogwarts Sorting Hat And I can cap them all.

There's nothing hidden in your head The Sorting Hat can't see,
So try me on and I will tell you Where you ought to be.

You might belong in Gryffindor,
Where dwell the brave at heart,
Their daring, nerve, and chivalry Set Gryffindors apart;