Fortification of Dorchester Heights - Fortification

Fortification

Washington first placed some of the heavy cannons from Ticonderoga at Lechmere's Point and Cobble Hill in Cambridge, and on Lamb's Dam in Roxbury. As a diversion against the planned move on the Dorchester Heights, he ordered these batteries to open fire on the town on the night of March 2, which fire the British returned, without significant casualties on either side. These cannonades were repeated on the night of March 3, while preparations for the taking of the heights continued.

On the night of March 4, 1776, the batteries opened fire again, but this time the fire was accompanied by action. General John Thomas and about 2,000 troops quietly marched to the top of Dorchester Heights, hauling entrenching tools and cannon placements. Hay bales were placed between the path taken by the troops and the harbor in order to muffle the sounds of the activity. Throughout the night, these troops and their relief labored at hauling cannon and building earthworks overlooking the town and the harbor. General Washington was present to provide moral support and encouragement, reminding them that March 5 was the sixth anniversary of the Boston Massacre. By 4 am, they had constructed fortifications that were proof against small arms and grapeshot. Work continued on the positions, with troops cutting down trees and constructing abbatis to impede any British assault on the works. The outside of the works also included rock-filled barrels that, while appearing to be a part of the defensive structure, could be rolled down the hill at attacking troops.

"The rebels have done more in one night than my whole army would have done in a month."

Washington anticipated that General Howe and his troops would either flee or try to take the hill, an action that would have probably been reminiscent of the Battle of Bunker Hill, which was a disaster for the British. If Howe decided to launch an attack on the heights, Washington planned to launch an attack against the city from Cambridge. As part of the preparations, he readied two floating batteries and boats sufficient to carry almost 3,000 troops. Washington's judgment of Howe's options was accurate; they were exactly the options Howe considered.