Private signals by day for the ships of war of the United States, July 12, 1798
Sailing ships could look very similar at a distance. It was critical for ships to identify each other as soon possible to avoid friendly fire, but at the same time, ships often sought to deceive the enemy about their identity. Complex signal arrangements like the ones listed in this document were intended to provide clear identification while making it impossible for an enemy to present themselves as a friendly vessel. In addition, the U.S. Navy had separate coded signals for identifying friendly British ships [see 2506.1, Box 1, Folder 105] and for merchant ships being escorted as part of a convoy [see 2506.1, Box 1, Folder 104].