It was at the beginning of January, 1865. General Butler, commanding the Army of the James, was expected to reach and capture Richmond by operating on the south side of the James River. His movements were blocked by the sinking of obstructions which rendered it impossible for him to navigate the stream, and by a powerful Confederate battery at French Beach.
To overcome these difficulties the resourceful Butler had caused a canal to be cut through the Dutch Gap peninsula, so that the enemy's batteries could be flanked and the obstructions in the river passed by the navy.
Nothing remained to be done but remove the great earthen bulkhead that separated the two bodies of water. This had been sapped and galleried, and more powder was packed away in it than was used in blowing up the famous "Crater" at Petersburg. The main body of troops had been drawn off from the neighborhood of the vast mine for safety, and it was supposed that none had been left behind but the few whose duty it was to light the fuse and then escape.
The supreme moment had arrived. The fuse had been lighted, and the officers were standing in a group at a safe distance discussing the question whether the work was to be crowned with success.
A member of General Butler's staff galloped up and shouted excitedly: "Has the guard opposite the bulkhead been withdrawn?
Somebody answered, hardly articulately, rather with a sort of gasp: "No!"
There was a score of men in the guard. There were tons of powder beside them. Fire was eating its way up the fuse and might at any second set loose the terrific force of the mine.
The bravery of the officers before whose minds those thoughts flashed could not be doubted — it had been proved too often for that —but to go and warn the squad seemed so utterly beyond reason, so surely a useless throwing away of another life, that they stood there rigid and pale, with one exception - Walter Thorn, first lieutenant of the U. S. Colored Infantry, who hesitated, but only long enough to form a resolve. Then he dashed off in the direction of the bulkhead.
Perceiving his intention, his fellow officers called to him to return — warned him, pleaded with him. Paying no heed, he ran on, reached the bulkhead, climbed to its summit, faced the storm of bullets that the rebels directed at him, and stood there until he had ordered the picket guard to flee to a place of safety.
He leaped from the top of the mine; the explosion took place; the earth was scattered in all directions and a great abyss remained, but the young lieutenant was unharmed.
"It was as deliberate an act of self-sacrifice and valor as was ever performed in our country or any other," said one of his superior officers.
Major
