A manuscript letter of prime significance in maritime history has recently come into the possession of The Marine Historical Association, Mystic, Connecticut. Contained in the letter copybook of Jeremiah Thompson, who took the prime initiative in developing the Black Ball Line of sailing packets and of bringing southern cotton up the coast to New York to provide eastbound cargoes for them, is a letter pertaining to the inauguration of the first line of regularly scheduled sailing packets. In this particular letter, reproduced below, Thompson and his three Quaker associates outline in detail to the two firms who, they hoped, would handle the Liverpool end of the shuttle, their plans for their project which would have the all-important effect of introducing the principle of “line” or “berth” service, with ships sailing on regular schedule between two ports.