When the British forces arrived from Savannah, General Clinton ordered his ground troops to encircle the city and make the major attack from the west against the strong fortifications. The Americans still had access to the mainland by crossing the Cooper River. On April 1, the British began the slow, tedious, and inexorable process of breaching the city’s defenses by using ancient siege techniques. This was a procedure that could have let d’Estaing and Lincoln take Savannah had the French not been so impetuous in making the disastrous frontal assault. The siege was simple in its execution, but costly in time and casualties. First, a deep, wide trench was dug parallel to the main fortification, just outside artillery range, at about eight hundred yards. The excavated dirt was thrown forward, creating a breastwork that protected men and weapons in the trench. Next, one or more narrow ditches were dug back and forth in a zigzag pattern toward the target fortifications, but always at an angle to the defending guns. The forward points of these ditches, or saps, soon became the focus of mortar and cannon fire, so the “sappers” were always in great danger.

After fourteen days of zigzag ditching, work was begun on a second parallel trench, dug at a range of about four hundred yards. Like the first, it was wide, deep, and protected by the parapet of excavated earth. Now, in closer range from the defenders’ guns, the sappers’ work became even more difficult, and every effort had to be made to keep the points of their ditches deep, narrow, and protected by frames of logs or thick timbers that were pushed ahead to absorb the hail of incoming bullets and shrapnel. As much of the work as possible was done at night. The British maintained a strong body of infantry and artillery in the closest parallel trench to repel any American sorties against the sappers.