On the night of the 28th, Hancock's corps was secretly withdrawn from the north side, and every preparation was made for the great forthcoming event.

Grant had constructed a mine under one of our forts in front of Petersburg, the main gallery of which was five hundred and twenty-two feet in length, with eight side galleries; in each of these galleries was placed about fourteen hundred pounds of powder. Gen. Burnside, in charge of this new feature of warfare, was to explode the "infernal machine," and walk into Petersburg with his colored troops, supposedly unmolested.

About daylight on the morning of the 30th, this famous mine—afterwards known as the "crater"—was exploded with a great noise, as of a "rushing mighty wind, and there was a great earthquake, and the sun became black." About one hundred of our men and three or four guns were moved out of their places into the air, and when the smoke cleared away an opening about one hundred and fifty feet long, sixty feet wide, and thirty feet deep appeared in place of our earthworks. Simultaneously with this explosion the enemy opened a terrific fire along their whole front, and the white division selected for this occasion came slowly through the abattis up to this hole, where they were met by a merciless fire from our artillery, enfilading them right and left, with our infantry in their front. They were badly led, and, being demoralized, they faltered and sought shelter in the crater. Next came the "nigger" division, and the "colored troops fought bravely," until the withering fire from our guns created a panic, when into the crater pell-mell they rushed, white and black, a disordered, mangled, quivering mass; our shot, shells, balls, and canister creating a perfect carnival of death. Some few endeavored to leave the crater and run back, but they were immediately shot down. Those who witnessed the scene say it was beyond the power of words to describe. Our lines were soon re-established, and our brigade was sent to relieve the troops holding the lines where the mine was sprung. Thus ended this "miserable affair."

The space between the two lines, as now formed, was so close as to endanger any exposure whatever, and we had to hug our earthworks very closely. Our company was in line immediately at the crater. In our front, and almost under our noses, lay the bloated, festering bodies of their dead, exposed to the scorching rays of a July sun. To make our situation still more interesting, it was supposed that the battery on our right was also mined; and we were daily and nightly in fear of another explosion, and to be landed—no telling where. We remained in this position for a week, when Grant asked for a truce to bury his dead. We were then moved a short distance to our right, where we remained until about the middle of August. While on these lines, we literally lived under the ground. We had to pass to and from the front in covered ways; our rations were all prepared in the rear, and sent to us. We were compelled to sleep in bomb-proofs to avoid their mortar shells, with which they enlivened the scene at night.

On the 18th of August, Warren's corps seized a portion of the Weldon Railroad near Petersburg, when we were withdrawn from our position in front of the city and moved to this point. On the 25th, this success was followed up by an attempt under Gen. Hancock to take possession of Ream's Station, farther south, on the same road. A. P. Hill's corps was selected to drive him from this position. On our arrival we were deployed in line, and ordered to go forward. The undergrowth and fallen trees over which we had to climb our way retarded our advance, and Gen. Cooke ordered the 27th and 48th regiments forward first. When they had gotten sufficiently advanced, he directed the other two regiments of our brigade, the 46th and 15th, to advance. When we reached the enemy's works, we found them heavily manned with infantry and artillery. Nothing daunted, however, we still advanced through shot and shell until we came to a hand-to-hand fight across the breastworks. The two other regiments now came up and in a few moments the enemy broke and fled in confusion, leaving their guns. The colors of the 27th, carried by Sergeant Richards, of the Orange Guards, were the first seen on their works. We pursued them, and turned their own guns upon them; but having no friction primers, we could not use them to advantage. We captured over two thousand prisoners and twelve pieces of artillery.

Our loss in this brilliant dash was very heavy, and North Carolina's troops alone, consisting of Cooke's, McRea's, and Lane's brigades, were engaged. The 27th regiment came out of the fight with less than seventy-five men!

The Grays lost in killed, private John Coltrain; in wounded, Sergeants William U. Steiner and A. C. Cheely, privates Hardy Ayers, James S. Scott, Emsley W. Stratford, and Wash. Williams.

Warren had now made good his hold upon the railroad, and these events did not materially affect the general result. The enemy's left gradually reached farther westward, until, in October, it was established on the left bank of Hatcher's Run, eight miles southwest of Petersburg.