Relief shown by spot heights. "*GPO: 2011--365-615/80636." Title from panel. Includes descriptive list of points of interest, 3 insets showing canal system in 1823, 1836, and 1848, diagram showing vertical drops for locks, and col. ill. Text, ill. (some col.), map showing ethnic enclaves in 1912, and background image consisting of part of 1845 map of Lowell by G.W. Boynton on verso. Available also through the Library of Congress Web site as a raster image.
United States. National Park Service
2011
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