Earl Percy’s Map of the Route to Safety

American Heritage just shared a scoop in Edwin S. Grosvenor‘s article “Discovered: First Maps of the American Revolution.”

It’s based on a return visit to the seat of the Dukes of Northumberland, a title bestowed on Earl Percy’s father and inherited by him after his return from the American war.

Grosvenor writes about one document:

On the newly found map, Percy had drawn his route from Lexington to Menotomy and back to Boston. “He's sketching the line of march,” observed local historian Michael Ruderman, studying the new Percy map. “It's the theatre of battle, the hostile territory he had to travel during the afternoon. And he's sketching the landmarks that were significant to him like the Old Powder House tower that he passed on his left."

The Percy map provides many details about the landscape, roads, taverns, and houses that existed in 1775.

Percy averted an even greater disaster by marching his 1,700 men by an unexpected route. Rather than continuing straight to Cambridge, he took a left turn to head to the Charlestown neck, where the ships of the Royal Navy could protect his force with their guns and ferry him across the Charles River, back to Boston.

For nearly 250 years, the maps lay forgotten in a box with dozens of other maps of Revolutionary war battles and encampments brought back by Gen. Percy.

The caption explains: “When rotated with north facing up, the town of Medford is in the upper left, with the home of ‘Col. [Isaac] Royal’ marked outside the town.” At the center, looking like rude high-school graffiti, is the Charlestown powderhouse.

In the lower right corner is Cambridge. Along the bottom is the road from Menotomy village into central Cambridge with several landmarks labeled: “Menotomy mill:g House,” “Adams’s Tavern,” “Brook,” “Grove of Locust Trees,” and “Tavern.”

The last stands at the crucial corner where Col. Percy turned his column onto “Kent’s Lane through which the Troops return’d from Concord” to Charlestown.”