He stuttered to a halt.

"My subject is History of Magic," he said in his dry, wheezy voice. "I
deal with facts, Miss Granger, not myths and legends." He cleared his
throat with a small noise like chalk s!-ping and continued, "In
September of that year, a subcommittee of Sardinian sorcerers -"

He stuttered to a halt. Hermione's hand was waving in the air again.

"Miss Grant?"

"Please, sir, don't legends always have a basis in fact?"

Professor Binns was looking at her in such amazement, Harry was
sure no student had ever interrupted him before, alive or dead.

"Well," said Professor Binns slowly, "yes, one could argue that, I
suppose." He peered at Hermione as though he had never seen a
student properly before. "However, the legend of which you speak is
such a very sensational, even ludicrous tale -"

But the whole class was now hanging on Professor Binns's every
word. He looked dimly at them all, every face turned to his. Harry
could tell he was completely thrown by such an unusual show of
interest.

"Oh, very well," he said slowly. "Let me see ... the Chamber of
Secrets ...

"You all know, of course, that Hogwarts was founded over a thousand
years ago - the precise date is uncertain - by the four greatest witches
and wizards of the age. The four school Houses are named after
them: Godric Gryffindor, Helga Hufflepuff, Rowena Ravenclaw, and
Salazar Slytherin. They built this castle together, far from prying
Muggle eyes, for it was an age when magic was feared by common
people, and witches and wizards suffered much persecution."

He paused, gazed blearily around the room, and continued.