This is a scholarly study of the Norse discoveries and explorations in America, from 982 to 1362. The early part of the book deals with the more or less accepted facts about Eric the Red and Lief the Lucky. Then he goes on to the Knutson voyages, less familiar to most readers, and the last part of the book presents all the arguments pro and con, relating to the Kensington Stone in Minnesota, as evidence that the Norsemen got that far. He debates the points, and proves to his own satisfaction that they did, and that the survivors stayed behind and intermarried with the Indians. Can't see a general sale for this as it is a carefully documented study for scholars.