to move at a moment's notice. At 7.30 o'clock we took up our line of march with 582 muskets, including First Company Andrew Sharpshooters, Captain J. Saunders, attached to this command, being the third regiment in the brigade line. We moved in a direct line toward the ground held by the forces under command of General Hooker, fording, in the march, Antietam Creek. On reaching the field, a line of battle was formed, in which my command occupied the position of third regiment of the first line. We then moved forward in line under a severe artillery fire about one mile over the ground gained by General Hooker, passing fences, fields, and obstacles of various descriptions, eventually occupying a piece of woods, directly in front of which, and well covered by the nature of the ground, field of grain, hay-stacks, buildings, and a thick orchard, were the enemy in strong force.

At this time we were marching by the right-oblique, in order to close an interval between my command and that of Colonel Hudson, Eighty-second New York Volunteers, and as we gained the summit of a slight elevation my left became hotly engaged with the enemy, covered as before mentioned, at a distance of not more than 15 yards. A section of the enemy's artillery was planted upon a knoll immediately in front of and not more than 600 yards distant from my right wing. This was twice silenced and driven back by the fire of my right wing, concentrated upon it. The engagement lasted between twenty and thirty minutes, my line remaining unbroken, the left wing advancing some 10 yards under a most terrific infantry fire.

Meanwhile the second line of the division, which had been halted some 30 or 40 yards in our rear, advanced until a portion of the Fifty-ninth Regiment New York Volunteers, Colonel Tidball, had closed of my men were by this maneuver killed by our own forces, and my most strenuous exertions were of no avail either in stopping this murderous fire or in causing the second line to advance to the front. At this juncture General Sumner came up, and his attention was immediately called by myself to this terrible mistake. He immediately rode to the right of the Fifty-ninth Regiment, ordered the firing to cease and the line to retire, which order was executed in considerable confusion.

The enemy soon appeared in heavy columns, advancing upon my left and rear, pouring in a deadly cross-fire on my left. I immediately and without orders ordered my command to retire, having first wit nested the same movement on the part of both the second and third lines. We retired slowly and in good order, bringing off our colors and a battle-flag captured from the enemy, reforming by the orders of General Gorman in a piece of woods some 500 yards to the rear, under cover of our artillery. This position was held until I was ordered to support a battery planted upon the brow of a hill immediately in our rear, the enemy having opened again with artillery. His fire being silenced, the position was held throughout the day.

I desire to say that my entire regiment behaved most gallantly during the engagement, evincing great coolness and bravery, as my list of casualties will show. Although suffering terribly from the fire of the enemy, it was with great surprise that received the order to retire, never entertaining for a moment any idea but that of complete success, although purchased at the cost of their lives. The order forbidding the carrying wounded men to the rear was obeyed to the very letter.

Of my line officers, without exception, I cannot speak in too high praise. They were all at their posts, bravely and manfully urging on