The line formed along the salient, though, as a way for Confederate defenders to take advantage of a stretch of high ground that helped them resist the Union attacks on May 8. Confederate engineers who inspected the line found the salient worrisome, but they also feared the consequences of what might happen if they did not deny the high ground within the salient to the Union army. Lee, himself an engineer with an eye for terrain, expressed reservations about the salient. The Second Corps commander, Lt. Gen. Richard S. Ewell, overseeing that portion of the line, assured Lee that his men could hold the position. Confederate officers were convinced that if they could pack enough artillery into the salient they would have very little trouble holding the line. Lee allowed the position to stand.
Soldiers from both armies spent the night of May 8-9 digging fortifications, and by the following morning, lines of breastworks stretched from the Po River on the western flanks to the Mule Shoe on the northeast. “Trees were felled and piled upon each other, and a ditch dug behind them with the earth out of it thrown against the logs,” said Confederate Brig. Gen. James Walker of the Stonewall Brigade, posted along the west face of the Mule Shoe. “The limbs and tops of the trees as cut off from the trunks were used to form abattis, by placing them in front of the breastworks with the sharpened points towards the enemy.” Walker described the “very formidable line of fortifications” as “apparently impregnable.”7
To make the Mule Shoe less susceptible to enfilading fire, Confederates constructed traverses—earth-and-log walls that ran back perpendicular from the main earthworks—every 20-40 feet. Soldiers called the spaces between the traverses “hog pens.”
Neither army passed up the chance to make their position even stronger. “Each army would fortify at night, and through the day, when not fighting, in order to hold the ground they had gained, and resist an attack,” wrote Stonewall Brigade member John O. Casler. Confederates would eventually construct a secondary line of works behind the main line along the northwestern face of the Mule Shoe, as well as a reserve line across the salient between the McCoull house and the Harrison house.
Throughout May 9, the armies continued to probe each other. Grant, continuing to take a more direct hand in the operation of the Federal army, ordered attacks against both Confederate flanks. The fighting along the western flank, although fierce, amounted to little because Lee shifted in reinforcements using his position’s interior lines. The fighting along the eastern flank amounted to even less because of the terrain and foot-dragging by IX Corps commander Ambrose Burnside.
The most notable event on May 9 happened early, around 9:00 a.m., near the center of the Union position. A sniper killed Maj. Gen. John Sedgwick shortly after the VI Corps commander boasted that Confederate sharpshooters “couldn’t hit an elephant” at their range. As his replacement, Meade promoted Maj. Gen. Horatio G. Wright to command the corps.
On May 10, Grant approved an attack against the western face of the Mule Shoe. Col. Emory Upton led twelve regiments in a quick strike across 200 open yards, designed to punch a hole through the Confederate lines (see Map, Pp. 10-11). The tactics were innovative: Instead of deploying his men shoulder to shoulder in a long thin line a half-mile wide, Upton chose to mass his men in a formation three regiments wide by four regiments deep. It allowed Upton to hit on a narrow front, boring through the Confederate line much like a modern bazooka round bores through armor. After Upton’s first line punched the hole, two regiments wheeled to the right and one wheeled left. The second and third lines acted as a phalanx, pushing straight ahead with the weight of the men to exploit the hole. The fourth line acted as a reserve.
Upton’s attack was initially successful, but lack of support forced him to eventually withdraw his men. He did manage to capture some 1,000 prisoners and, more importantly, demonstrate that the Confederate salient was vulnerable. Emory Upton was promoted to brigadier general for his work.
Grant had “but little doubt” that Upton’s assault “would have proved entirely successful” if it had been timed better and properly supported.8 Keeping in mind those mistakes, he began to formulate a new plan quite similar to Upton’s—but on a much larger scale.
