Routine biography about an off-the-beaten-tracker. Connecticut-born Ledyard sailed with Cook (1776), noted cultural convergences among the Pacific islanders, and speculated on common origins, trying to connect them to the American Indians. He also realized the fur potential in Pacific waters and tried to establish a trade between the Pacific Northwest and China, a plan involving an abortive trek across Russia. Diverted to Africa, he died shortly after starting to look for the source of the Niger. Here he is introduced as a ""primordial ethnologist""--a grandiose label for a man who made the grand tour the hard way and whose observations reflect beginning theory about relationships between ethnic groups. Straight except for a surfeit of dialogue.