Dot’s “letter” today is a postcard with an aerial photo of a section of Lake Sunapee. On it, she’s traced a pencil line hugging the shore  into the mouth of Sunapee Harbor. This, she explains, is the route she took on her early morning canoe trip. She writes that she wishes she had more than a day in her beloved spot, but she’s happy to be there for even that short a time. How she wishes Dart could be there with her. Be patient, Dot. You have years ahead of you…