...er to Mystic Pond, through the pond and Symms' River to Horn Pond in Woburn, and through said pond to the head thereof. Meeting here bars they could neither let down nor remove, they went back to Richardson's Mill on Symms' River, and passed up the valley through the east part of Woburn to Wilmington, and found an easy and very regular ascent until they reached the Concord River, a distance traveled, as the su...