The man at the dry cleaner's had looked at the hat, then at Dirk, then at the hat again. He had suggested that Dirk buy a new hat. When that was met with flat disapproval, the man had kindly, gently, explained that any process they might us that had a fair chance of truly removing the offending matter would also stand a fair chance of removing portions of the hat. Mere felt could only withstand so much.
Now he sat at home, at the kitchen table, with a dishrag, warm water, and the gentlest detergent he had been able to find. As he cleaned-carefully, gently, painstakingly, Dirk crooned to his hat. "Poor thing, don't you worry, I'll get them back, you'll see. If I have to hire a bloody helicopter to dump feces on every popular statue in the park, I'll get them back. Mean old pigeons."