This most important battle plan of the New England theater of war shows, in detail, the American fortifications on Dorchester Heights forcing the British to leave Boston in 1776. This was the best printed plan of the city of Boston and its environs, to date. Finely engraved in aquatint and beautifully printed on heavy paper, this copy is one of perhaps six known examples signed in manuscript by the author. Pelham, a Loyalist, was born in Boston in 1748/9. The note that was engraved in the upper left of this map is a copy of the passport issued to Pelham two months after the Battle of Bunkers-Hill, giving him permission to examine the enemy lines. The aquatint is of interest, because of its high quality. It is known that Pelham consulted John Singleton Copley (Pelham's half brother) regarding the production of this map. Pelham was eleven years Copley's junior, and there is little question that Pelham learned to draw from his accomplished elder. The outstanding result is without question the finest cartographical print relating to the Revolutionary War.