Saturday, July 26, 2014

The 48th/150th: The Mine Completed, Charged, & Tamped. . . .

Entrance to the 48th's Mine at Petersburg
In all, it had taken just about one month for the soldiers of the 48th Pennsylvania Infantry to complete the tunneling of their mine at Petersburg. Having developed the idea and discussed it with a few of his confidantes in the regiment, Colonel Henry Pleasants next took his proposal of divisional commander Robert Potter who then suggested the Pennsylvania colonel and former mining engineer take the idea directly to General Burnside. Late on the evening of June 24, 1864, Burnside approved of Pleasants's endeavor and, next day at exactly 12:00 noon, Pleasants watched as his men began digging into the Virginia soil.
The actual digging was left to the 99 trained, professional miners in the regiment; every one else, though, played important supporting roles: building the timber framing, and especially removing the dirt. By the time the mine was fully completed, Pleasants estimated that approximately 18,000 cubic feet of earth had been removed from the ground, and either taken far to the rear or used to fill sandbags.
Forced to use improvised and modified tools, Pleasants and his dirt-covered and sore-shouldered soldiers in the 48th Pennsylvania labored under severe disadvantage. They received little, if any, support from the army and especially from the army's engineers, who believed the thing could not be done. The soldiers of the 48th were not even provided with lumber for the framing while even Pleasants's simple request for a surveyor's tool--needed to gauge exact distance--was denied.

But the thing was done. The main tunnel, extending some 510 1/2 feet and ending directly underneath Elliott's Salient, was completed on July 17; the next day, work on the right and left lateral galleries commenced. Respectively, the left and right galleries were 37' and 38' in length and in each of these galleries, chambers were dug for placing the magazines. It took another few days to complete the galleries, but by nightfall on July 23, the mine was finished. All that was left was placing the powder and laying the fuse.

Pleasants reported the completion of his mine to Burnside who, in turn, notified army commander Meade. Meade then requested that Burnside submit his plan for using the mine. Burnside's response, written on July 26, 1864, was the sooner, the better; rain and Confederate countermines might ultimately ruin the entire endeavor.  As the whiskered corps commander wrote, "It is altogether probable that the enemy is cognizant of the fact that we are mining, because it is mentioned in their papers, and they have been heard at work on what are supposed to be shafts in close proximity to our galleries. But the rain of night before last has, no doubt, much retarded their work. We have heard no sound of workmen in them either yesterday or today; and nothing is heard by us in the mine but the ordinary sounds of work on the surface above. This morning we had some apprehension that the left lateral gallery was in danger of caving in from the weight of the battery above it and the shock of their firing. But all possible precautions have been taken to strengthen it, and preserve it intact. The placing of the charge in the mine will not involve the necessity of making a noise. It is therefore probable that we will escape discovery if the mine is to be used within two or three days. It is nevertheless important, in my opinion, that the mine should be exploded at the earliest possible moment consistent with the general interests of the campaign." Following the explosion of the mine, Burnside planned to use his Fourth Division, composed entirely of black soldiers.
Meade received Burnside's plan and agreed that the mine should be charged and exploded sooner rather than later. However, he did not agree with Burnside's choice of using the black troops to spearhead the attack. Meade (and Grant) had paid little attention to Burnside and the 48th's mine throughout the previous month but now, at almost the eleventh hour, they took an interest and literally pulled the rug out from under Burnside's feet, with tragic consequences.
In the meantime, Pleasants received orders on July 27 to begin placing the powder; it took six hours, from 4:00 p.m. that afternoon until 10:00 p.m. that night. Pleasants had requested 12,000 pounds of powder but received 8,000. It arrived in legs, one wagon load at a time. And since the drivers of these wagons did not want to get too close to the front, the soldiers had to carry all 320 kegs of powder from a position roughly one mile to the rear then down the entire length of the tunnel and to the lateral galleries, where Pleasants awaited. As the colonel later explained, "The charge consisted of three hundred and twenty kegs of powder, each containing twenty-five pounds--four tons. It was placed in eight magazines, connected by wooden tubes, half filled with powder. These tubes met from the lateral galleries at the inside end of the main gallery, and from this point I placed three lines of fuses for a distance of ninety-eight feet." The fuses had to be spliced.

Carrying In The Powder Kegs

Placing The Powder In Magazines

As soon as the powder was placed in the magazines, work began immediately on the tamping, which consisted of bags filled with dirt--thousands of them, it seems. The tamping began at 10:00 p.m. on the night of July 27 and continued until 6:00 p.m. the following day. "Thirty four feet of main gallery was tamped," said Pleasants, "and ten feet of the entrance of each of the lateral galleries, but the space between the magazines was left clear of tamping." Oliver Bosbyshell further explained that the tamping "was about forty feet in length, and consisted of bags of sand placed loosely on one another, with long logs laid diagonally across the gallery, so as to be driven into the sides by the recoil of the explosion. Common blasting fuse was furnished, in pieces, instead of one continuous piece, which Colonel Pleasants was obliged to splice together. These lines were used ninety feet long, and placed in a wooden tube lined with canvas to guard it from the dampness. The tamping was finished and the mine was ready to be fired at 6 p.m. of July 28."
It was quite the extensive undertaking but by the evening of July 28--just about one month since the first shovel full of dirt was removed--the 48th's mine was finished, charged, and tamped. . .all Pleasants could do now was await the orders to fire it. 

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