Major-General Ambrose E. Burnside’s Ninth Corps of the Army of the Potomac held the center of the Federal siege line outside Petersburg, Virginia. In its front, about 150 yards away, troops of General Robert E. Lee’s Confederate Army of Northern Virginia held a strong redoubt on high ground called Elliott’s Salient. A soldier of the 48th Pennsylvania (a regiment of anthracite coal miners from Schuylkill County) remarked, “We could blow that damn fort out of existence if we could run a mine shaft under it.”
Lieutenant-Colonel Henry Pleasants commanded the 48th and was a mining engineer. He overheard the soldier and developed a plan that he submitted to his superior, Brigadier-General Robert B. Potter. In later congressional testimony, Potter said:
“About the 24th of June, the idea of mining under the enemy’s works in my immediate front was suggested to me; in fact, I had thought of it before, and several others had thought the same thing… Pleasants… came to my quarters and suggested to me that he was familiar with mining, and that many of the men in his regiment were miners, and that they thought they could undermine one of the enemy’s works in my immediate front. After some conversation with him, I wrote a communication to General Burnside… suggesting this plan of mining the enemy’s works, and giving some of the details.”
Potter wrote Burnside that Pleasants–
“–is of the opinion that they could run a mine forward at the rate of from 25 to 50 feet per day, including supports, ventilation, and so on. It would be a double mine, for as we cannot ventilate by shafts from the top, we would have to run parallel tunnels, and connect them every short distance by lateral ones, to secure a circulation of air, absolutely essential here, as these soils are full of mephitic vapors.”
Burnside summoned Potter and Pleasants to his headquarters on the night of the 24th. Pleasants later testified that he “explained to him carefully the mode of ventilating the mine and everything about it. He seemed very much pleased with the proposition, and told me to go right on with the work.”
Burnside then sought approval from Major-General George G. Meade, commanding the Army of the Potomac. Meade knew that the only way to overcome the Confederates’ impregnable fortifications was to place them under siege. But the Federal investment of Petersburg was not truly a siege operation, as there were not enough troops to surround the city. So when Meade was approached with the tunneling plan, he was willing to give it a try. He wrote:
“I sanctioned its prosecution, though at the time, from the reports of the engineers and my own examination, I was satisfied the location of the mine was such that its explosion would not be likely to be followed by any important result, as the battery to be destroyed was in a re-entering part of the enemy’s line, exposed to an enfilading fire, and reverse fire from points both on the right and left.”
When Meade was asked by General-in-Chief Ulysses S. Grant if there was any way to extend the Federal lines to weaken the Confederate defenses, Meade replied that he did not see a way, but he presented the tunneling plan to him as an alternative. Meade wrote that when the mine was completed, “General B. thinks when exploded will enable him by a formidable assault to carry the line of works.”
Grant later wrote in his memoirs that he approved it only “as a means of keeping the men occupied.” Many Federal engineers called the project “claptrap and nonsense” because ventilation limitations prevented shafts from being longer than 400 feet. However, Pleasants’s innovative and undetectable ventilating system enabled this shaft to eventually stretch 511 feet.
Digging started on the 25th, with the men using their bayonets and makeshift tools. A civilian’s theodolite enabled Pleasants to survey for direction and distance. The tunnel would run uphill, thereby allowing for drainage. As he testified, “My regiment was only about 400 strong. At first I employed but a few men at a time, but the number was increased as the work progressed, until at last I had to use the whole regiment, non-commissioned officers and all.”
A soldier of the nearby 13th Ohio watched the Pennsylvanians and later wrote, “The dirt was carried out in cracker boxes and jute bags which had contained grain for the commissary department. The men working in the mine had only shirt and drawers on, and some were minus shirt even. I used to watch them popping in and out of the hole like so many brown gophers.”
The tunneling originated in a steep embankment behind the Federal picket line, out of Confederate view. Even so, on the last day of June, Confederate Brigadier-General E. Porter Alexander warned that Federals were tunneling under Elliott’s Salient. But Confederate engineers, like their Federal counterparts, did not believe that men could dig a tunnel long enough to reach their lines. The work continued into July.
Bibliography
- Bearss, Edwin C. with Suderow, Bryce, The Petersburg Campaign: The Eastern Front Battles, June-August 1864, Volume I. El Dorado Hills, Calif.: Savas Beattie LLC; Casemate Publishers, Kindle Edition, 2012.
- Catton, Bruce, The Army of the Potomac: A Stillness at Appomattox. Garden City, NY: Doubleday & Co., Inc., 1953.
- Davis, William C., Death in the Trenches: Grant at Petersburg (Alexandria, VA: Time-Life Books, 1983), p. 67-68;
- Foote, Shelby, The Civil War, A Narrative: Red River to Appomattox. New York: Vintage Civil War Library, Knopf Doubleday Publishing Group (Kindle Edition), 2011.
- Linedecker, Clifford L. (ed.), Civil War A to Z. New York: Ballantine Books, 2002.
- Long, E.B. with Long, Barbara, The Civil War Day by Day. New York: Da Capo Press, Inc., 1971.
- McPherson, James M., Battle Cry of Freedom: The Civil War Era. Oxford History of the United States Book 6, Oxford University Press (Kindle Edition), 1988.
- Wert, Jeffry D. (Patricia L. Faust ed.), Historical Times Illustrated Encyclopedia of the Civil War. New York: Harper & Row, 1986.