MIDDLEBURY — Children’s librarians wear many hats. They are storytellers, teachers, mentors, performers, listeners, event planners. Ilsley Public Library’s Tricia Allen wears many literal hats, too. Every Thursday through the summer she dresses up in a homemade costume — sparkly house fly, rainbow unicorn — loads great piles of books into a trailer and lugs them across town on her bike. She calls it the Book Bike. When she arrives at Middlebury’s rec park, children and their caregivers are milling around th … (read more)