On the afternoon of April 11 the 63d Pennsylvania Volunteers, while on picket duty in the woods to the left of the Yorktown road, was attacked by the enemy. The 57th was ordered to its assistance and advancing at double quick, formed in line of battle, moving over the open field in face of a hot fire and quickly putting to flight the columns of the enemy, driving them back to the protection of their heavy batteries. In this short but exciting engagement, the regiment lost by wounds two men, Samuel Merven, of Company E, and John Cochran, of Company F. Cochran subsequently died from the effects of his wound and Merven was discharged. In this engagement, insignificant as it was, compared with its after battles, the regiment exhibited great coolness and gave token of its ability and readiness for future duty and service. An incident occurred about this date, while the regiment was on picket duty, that is worthy of passing notice. Lieutenant Wagner, of the topographic engineers, was engaged in making drawings of the Confederate works. He had placed a camp table in an exposed position and spread his drafting material upon it. The white paper made an excellent target for the enemy's gunners. One of their shots struck the table and fatally wounded the lieutenant. A few moments after he rode along the rear of our lines, his shattered and bleeding arm dangling at his side. This shot is referred to, after these many years, by General Longstreet in his recent work, as one of two of the most remarkable shots, for accuracy of aim, of the war. He says: "An equally good one (shot) was made by a Confederate at Yorktown. An officer of the topographical engineers walked into the open in front of our lines, fixed his plane table and seated himself to make a map of the Confederate works. A non-commissioned officer, without orders, adjusted his gun, carefully aimed it, and fired. At the report of the gun all eyes were turned to see the occasion of it, and then to observe the object, when the shell was seen to explode as if in the hands of the officer. It had been dropped squarely upon the drawing table and Lieutenant Wagner was mortally wounded."--Gen. Longstreet, in "From Manassas to Appomattox." This shot appears, by a note to the text written by Capt. A. B. Moore, of Richmond, Va., to have been fired by Corporal Holzbudon, of the 2d company, Richmond Howitzers, from a ten-pound parrott gun. Another incident more immediately connected with the regiment, worthy of a place in its history as an exhibition of accurate firing, occurred here. On the left of our regimental picket line was stationed a section of a field battery whose duty was to shell the enemy's works and prevent their annoying our lines. For some time Colonel Campbell watched with manifest disgust the green cannoneers blazing away at random, and with evidently little effect. At length stepping to one of the guns the colonel said: