Springing the Mine
The Tunneling Operations of Petersburg

     Ninth Army Corps headquarters announced at 2:45 pm on the 25th of June 1864 the commencement of its work on mining operations to extend itself below the Confederate batteries on that portion of the Petersburg line. Lieutenant Colonel Henry Pleasants; commanded the 48th Pennsylvania Infantry, made up largely of Western Pennsylvania coal miners, determined that such a scheme could be pulled off in breaking through the rebel defenses.

     No sanctioning had been received by general headquarters, Army of the Potomac regarding this surprise feat of engineering. Major General George Gordon Meade simply authorized the continuance of its operation; but had not thought the location of it a proper one. It was his opinion, the Confederate position on both flanks was too strong and their interior lines along the Jerusalem Plank Road equally as formidable.

     It was not surprising for Lieutenant General Ulysses S. Grant to buy into what may have been believed to be a hair brained scheme developed by these Pennsylvania soldiers. He had seen the success of such an endeavor more than a year earlier at Fort Hill inside Vicksburg; and desired only that the mine be used in connection with the current operations against that portion of the line.

     The materials used to excavate the mine had to be improvised. The picks were made in like fashion to those used by the pioneer companies. The initial planks supporting the shaft were used from a torn down bridge until a saw mill some distance away was able to furnish more. The soldiers of the 48th Pennsylvania Infantry used cracker boxes and hand barrows to remove the freshly dug earth. The work itself went steady until early July when the ground being dug through became extremely wet and nearly caused a collapse. Work had been temporarily stopped in order for it to be re-timbered.

     The main gallery had been reported to 2nd division headquarters, Brigadier General Robert B. Potter, as being completed on the 20th of July; and was reported as being 510.8 feet in length. The right gallery was extended a little beyond the works of the enemy. The left was reported as being 37 feet in length and completed at midnight on the 22nd. The right was 38 feet in length and work stopped on it at 6 pm on the 23rd.

     Two hundred ten soldiers were detailed to the operation at one time and labored continually around the clock while only two personally attended to the mining itself. Eight magazines were dug out opposite each other along the two galleries, on each end and half way between. It was determined to place between 1,200 and 1,400 pounds of gunpowder in each, connected with a trough between them in order to fire it.

     Brigadier General Robert B. Potter; reported to corps headquarters that the mine had been ready to spring. From below, the enemy had been heard working within the batteries themselves, and likewise beneath the surface. The discovery of the Confederates attempting to countermine the operation gave the division commander a sense of urgency as that time would eventually cause its detection and measures taken to defeat it.

     Pursuant to orders received by Major General George Gordon Meade's headquarters, Brigadier General Robert B. Potter issued the necessary orders for the mine to be charged. One hundred eighty men were detailed to transport the powder from the wagons to the mine and placed under Captain Charles E. Mallam. Sticks four to six feet in length were issued to support the kegs that came in one hundred pound quantities.

     By 9:00 pm on the 27th of July, Lieutenant Colonel Pleasants reported that the right lateral gallery had been fully charged and was expecting the left gallery to be charged two hours later, tamped and completed by 4:00 am on the morning of July 28th.

     The usage of the black troops for the main assault once the mine was sprung initially did not meet with the approval of the Lieutenant General commanding. Only the meeting between Major General Meade and Major General Burnside on the 29th of July; when 9th Corps brought in its inspector general, Lieutenant Colonel Charles G. Loring, whose opinion was that after forty days of siege operations the only troops up to such an assault at that time were those of the coloreds. These, had drilled for it, and were already geared up to perform the task. His argument was convincing, the army commander conceded, and the General in Chief gave his approval.

     The morning of the big event, the 9th Corps Commander received a last minute reprieve signed by the army's chief of staff, Major General Andrew Humphreys that the 3:30 am hour initially designated to detonate the mine, was still terribly dark and gave the commander an option of a later hour. Burnside reassured army headquarters that the mine would go at the originally agreed on time.

     Lieutenant Colonel Henry Pleasants, himself lit the fuse at 3:15 am, but as sufficient time had passed and no explosion followed, an officer accompanied by a sergeant volunteered to investigate as to the reason. The fire had gone out at the splice and the fuses had to be relit. After much anxiety up and down the chain of command, the earth rumbled and shook at 4:44 am blowing the gaping hole in the earth.

     The infantry assault that followed had not provided the slightest semblance of success. The rebels were obviously stunned for more than a half hour after the detonation but the assaults that followed were completely uncoordinated. The results of which disappointed both army commander and General in Chief alike.

     It was Major General George Gordon Meade, who on August 3, 1864 preferred charges against the 9th Corps Commander, Major General Ambrose Burnside and furthermore informed him that he had asked of the Lieutenant General commanding the armies to have him relieved of any further duty with the army.

     Major General Ambrose Burnside would face the embarrassment of a court of inquiry composed of officers he had been serving with inside his own army for the past two years. The charges against him, disobedience to orders would have been better served presented to unbiased officers from outside of the army itself; but the War Department and White House did not agree.

     In spite of the court that was about to convene, Lieutenant Colonel Henry Pleasants, 48th Pennsylvania Veteran Volunteers, received the praise of the entire army for his masterpiece in engineering. Likewise on August 3, 1864, the following congratulatory was published:

          GENERAL ORDERS,            Hdqrs. Army of the Potomac,
               No. 32                               August 3, 1864
     The commanding general takes pleasure in acknowledging the valuable services rendered by Lieutenant Colonel Henry Pleasants, Forty-eighth Regiment Pennsylvania Veteran Volunteers, and the officers and men of his command, in the excavation of the mine which was successfully exploded on the morning of the 30th ultimo under one of the enemy's batteries in front of the Second Division of the Ninth Army Corps. The skill displayed in the laying out of and construction of the mine reflects great credit upon Lieutenant Colonel Pleasants, the officer in charge, and the willing endurance by the officers and men of the regiment of the extraordinary labor and fatigue involved in the prosecution of the work to completion is worthy of the highest praise.
          By command of Major General Meade:
          S. WILLIAMS,           Assistant Adjutant-General

     In theory the concept was brilliant. In operation, the idea was to take ground from an entrenched enemy. The execution of half a plan that cost so many more lives in the mismanagement that would follow; lead to the unfinished work of discovering the responsibility of its failure. Major General Ambrose Burnside was about to be sent home to await further orders; and the Federal Army of the Potomac would remain behind endeavoring to succeed another way in driving the Confederate forces out of Petersburg, Virginia.

Dan (Aldie) Daniel Moran
© 2005

Editors Note: Mr.Moran is a feature writer on the US-Civilwar.com writers staff. He may be contacted with your questions, ideas and requests at dmoran@us-civilwars.net