Long Island Sound Triangulation INDIGO
**Long Island Sound Triangulation INDIGO, 1881** This U.S. Coast Survey chart documents the triangulation network used to map Long Island Sound, spanning waters between New York, Connecticut, and New Jersey. The indigo colorway distinguishes this edition from the standard black and white versions of the same survey data. Printed on heavy paper stock with crisp line definition throughout the geometric plotting marks.
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Ready-to-hang
Designed with elegant margins by our cartographers and printed on master’s edition, museum-quality 250 gsm (110 lb) paper—off-white, uncoated, and chosen for its exceptional archival quality.
Our ready-to-hang premium wooden frames, handcrafted from responsibly sourced oak or ash, showcase unique natural grain patterns, adding warmth and character to every piece.