What is ironic about Mr. Avery's allusion to the Rosetta Stone? How does Scout show that she does not know his purpose for using this allusion?

    In Chapter 8 of Harper Lee's novel, To Kill a Mockingbird, Mr. Avery's declaration concerning the season's changing when children were bad came true, much to the chagrin of Jem and Scout.

Mr. Avery said that it was written on the Rosetta Stone that when children disobeyed their parents, smoked cigarettes and made war on each other, the seasons would change.

Shortly after, Scout awoke to a sight she had never seen: Snow. Mr. Avery's prediction had come true, and Jem and Scout felt that it was partly their fault. Later, Mr. Avery made another affirmation:

    "See what you've done," he said. "Hasn't snowed in Maycomb since Appomattox. It's bad children like you makes the seasons change."

Scout responds that

"... I did not wonder where Mr. Avery gathered his meteorological statistics: they came straight from the Rosetta Stone."

Since Mr. Avery had twice predicted correctly, Scout was sure that he had again gotten his information from the Rosetta Stone. She obviously did not know the true origins of the stone, one of history's first forms of written communication.