Rare blue back chart of Martha's Vineyard and Nantucket Sound. The larger chart extends from Holme's Hole, Nobska Pt., and Fallmouth Village in the west to Nantucket and the Shoals to the east, and Chatam. The second chart is an excellent highly detailed chart of Boston Harbor. First Edition of a very scarce chart. . The Blunts published very few charts after the Coast Survey started publishing its charts, and nearly all were large general charts, making this example highly unusual. Phillips, Maps of America, p. 389. Not in Crosby, Nantucket in Print. No example has appeared in a dealer catalogue or at auction in the past 20 years, except this example. JH Colton was one of the pre-eminent American map publishing firms in the mid-19th Century.