 He was an unknown 23-year-old working at a Cambridge bookstore when Thomas Taylor got a commission for the cover of a children's book. The author J.K. Rowling was as little known as he was. As the illustrator, Mr. Taylor read the manuscript. So he was one of the first people to get a glimpse of the world of Harry Potter and Hogwarts, where the world is magic and the rest are just muggles.