Engineers in Union blue and Confederate gray played a prominent role in the Vicksburg campaigns of 1862-1863. Although their contributions have largely gone unnoticed in published works on the campaign, the stories of these men and the fatigue parties that toiled under their supervision are worthy of note and will be detailed in this series of articles.
Part 20: Ax and saw, pick and shovel
The truce May 25 that enabled the Union dead and wounded to be removed from the field also provided engineers of both armies an opportunity to more closely examine the terrain in their fronts. Among them was Maj. Samuel Lockett, chief engineer of the Confederate army, who stood on the parapet of Stockade Redan. While attempting to evaluate enemy operations along Graveyard Road, Lockett recalled, “a Federal orderly came up to me and said that General Sherman wished to speak to me.”
Following introductions, Sherman, who prior to the war had been president of what is today Louisiana State University, pulled from his pocket some letters entrusted to him by Northern friends of members of the garrison and asked Lockett if he would deliver them before they “got too old.”
“Yes, general,” replied the engineer. “It would have been very old, indeed, if you had kept it until you brought it into Vicksburg yourself.”
“So you think, then, I am a very slow mail route,” commented Sherman.
“Well, rather, when you have to travel by regular approaches, parallels, and zigzags,” responded Lockett, whose statement accurately detailed the manner by which the men in blue would reduce Vicksburg.
Grant, too, came to the same conclusion. The ease with which his two assaults were repulsed convinced the commander of the Union Army of the Tennessee to lay siege to Vicksburg. By Special Orders Number 140, issued on May 25 by Lt. Col. John A. Rawlins, the army’s assistant adjutant general, Grant directed:
Corps commanders will immediately commence the work of reducing the enemy by regular approaches. It is desirable that no more loss of life shall be sustained in the reduction of Vicksburg and the capture of the garrison. Every advantage will be taken of the natural inequalities of the ground to gain positions from which to start mines, trenches or advance batteries. The work will be under the immediate charge of corps engineers, corps commanders being responsible that the work in their immediate fronts is pushed with all vigor.
Capt. Frederick Prime, chief engineer of the department, was charged with general superintendence of the whole work. In reference to Prime, Grant emphasized to his subordinates, “He will be obeyed and respected accordingly.”
For the remainder of May, Union engineers and fatigue parties that labored with ax and saw, and pick and shovel, slowly extended the lines to the left and right until the flanks were anchored on the Mississippi River above and below Vicksburg. Once the line of circumvallation was completed, the citizens and soldiers trapped in Vicksburg were cut off from all supply and communications with the outside world.
“With the navy holding the river, the investment of Vicksburg was complete,” boasted Grant in his memoirs. “As long as we could hold our position the enemy was limited in supplies of food, men, and munitions of war to what they had on hand.” With certain conviction he noted, “These could not always last.” Thus, Grant’s decision to “out-camp the enemy,” as he expressed it, was the sure course to follow.
Once the line of circumvallation was established, the engineers in blue opened thirteen approaches at various points toward the city’s defenses in textbook fashion. For the next six weeks, Federal soldiers toiled under a broiling Mississippi sun to sink approaches, parallels, and zigzags just as Lockett had foretold. Once siege operations began, the surrender of Vicksburg became a mathematical certainty.