Rising like a brick lighthouse above the rooftops of Portland, Maine, the 1807 Portland Observatory on Munjoy Hill dominates this early Detroit Publishing Company "Phostint" card — the only surviving maritime signal tower in the United States, its octagonal tapered form still commands the skyline of the Eastern Promenade neighborhood today. Detroit Publishing's brilliant lithochrome process renders the aged red brick in warm amber tones, the cupola's green copper cap glinting above a scalloped widow's walk, while a horse-era streetcar track bisects the cobbled foreground. Issued before the 1907 postal-regulation change that first permitted divided backs, this undivided-back card — with its "message on the left, address on the right" instructions printed in red — dates to the very opening years of the American postcard golden age, and its blank reverse suggests it was kept as a souvenir rather than sent.