Book excerpt: In Letters of Note: New York, Shaun Usher curates a collection of extraordinary written exchanges about the Big Apple, from the marvelling of wide-eyed newcomers and the devoted outpourings of native citizens, to the frustrated outcries of the dispossessed and the fond reminiscences of old-timers. Includes letters by: Italo Calvino, Ralph Ellison Kahlil Gibran, Helen Keller, Martin Scorsese Saum Song Bo, Rebecca West & many more.