Ben and Jim visit Jed Turner's trading post, which is located on an island in a lake. They find the post deserted and upon investigation find Jed's wife and child in a canoe. Jed has been captured by hostile Huron Indians. Later Ben and Jim narrowly escape capture by an Algonquian war party. Late in the night, Ben and Jim rescue Ned and in the morning the Hurons and Algonquians engage in a battle.; Ben and his men escort two government surveyors into the uncharted Northwest Territory to reach the 82nd Meridian.