Decorated with "Signals at the Portland Observatory" of Portland, Maine with 24 flags and "Explanation" below (McCauley No. 260), the reverse decorated with two ships at sea, one flying an American flag and "Washington" inscribed on stern, both flying house flag with a "W"
note The Portland Observatory, a 86-foot high tower, became operational in 1807. Financed by a group of investors organized by Captain Lemuel Moody (1767-1846), the Observatory was used to alert ship owners and merchants that their vessels were approaching with the use of the signal flags, identifying type and location of ship.