"When you open a book," the sentimental library posters said, "anything can happen." This was so. A book of fiction was a bomb. It was a land mine you wanted to go off. You wanted it to blow your whole day. Unfortunately, hundreds of thousands of books were duds. They had been rusting out of everyone's way for so long that they no longer worked. There was no way to distinguish the duds from the live mines except to throw yourself at them headlong, one by one."