Report of Maj. Thomas S. Trumbull, First Connecticut Hoary Artillery.
DECEMBER 11-15, 1862.--Battle of Fredericksburg, Va.

December 19, 1862.

Col. R. O. TYLER,
Commanding Reserve Artillery.

    COLONEL: I have the honor to report that, in accordance with orders received, I moved at dusk on the evening of the 10th, with the batteries under my charge, consisting of Companies B and M, of the First Connecticut Artillery, the former of four and the latter of three 4-inch rifled guns. By 10 o'clock I had succeeded in bringing up my ammunition and in planting my guns in the position assigned, being a high bluff opposite the left of the town, and could at that time have opened fire had it been necessary.
    On Thursday morning at daybreak, in accordance with orders received, I directed my batteries to open on the town, which, from my position, was not visible until nearly 12 o'clock. I am satisfied that our shells, thrown into the town, burst with considerable effect, although that great desideratum which should accompany every artillery engagement, viz, the ability to see the object fired at, as well as the effect of the fire, was in this case wanting. I therefore ordered that in no case should the fire be more rapid than one round in from ten to fifteen minutes, until about noon, when the rising of the fog and smoke gave a better target and more satisfactory results.
    On Friday morning I received, through you, a request from General Franklin to silence, if possible, a battery which his picket informed him had been thrown forward during the night in front of his position. I was unable, owing to the dense fog and mist, to make out the precise point indicated, but paid my attention to the batteries skirting the woods and crowning the hills in front of his position.
    Although the firing was exceedingly accurate, I directed but few shots to be fired, since I was satisfied that firing at long ranges, and more especially at batteries of position, was productive of little effect.
    Early Saturday morning I directed the batteries under my command to fire with great caution, which I found to be necessary from the fact that some of our projectiles failed to take the grooves, thereby endangering the safety of the troops composing our advanced line. In firing at the six-gun battery directly in our front, and at the troops in the sunken road defending it, I found the precaution somewhat unnecessary. At this point, therefore, of the enemy's line, as well as at the batteries in front of Franklin's right, I directed my fire with considerable efficiency, many of my shells bursting both in their batteries and among  their troops, and one of their batteries, which had been struck several times in succession, failed to open fire again until nightfall of the same day.
    The main attack on Saturday having failed, and it being evident that it would not be immediately repeated, I directed my batteries to save their ammunition, except in cases of extreme necessity, or where the damage done would amply warrant the expenditure of the same. Acting under these instructions, therefore, my battery commanders reserved their fire until the day after our troops had recrossed the river. Several large bodies of the enemy at that time making their appearance on the plain in our front, I opened fire upon them with such effect that one brigade, at the extreme distance of over 2 miles, broke ranks in great disorder, while several other bodies moved off at doublequick. I consider this not only as an instance of remarkable accuracy of fire, but also as showing that the enemy, when unprotected by breastworks, are unable to equal in steadiness our own troops.
    After this, and until the truce, I held the field in my front under fire, so that large bodies were thenceforward unable to move across it or approach in any considerable numbers the pontoons on our left. I withheld my fire from the extreme right, where our dead were being stripped, in accordance with instructions from you that there might be burying parties among the enemy there congregated.
    I am happy to state that in the late engagement I suffered no loss either of men or animals.
    My whole expenditure of ammunition was 357 rounds, 4 in Schenkl shell, with metallic casing. I consider these defective on two accounts; first, that at least one in every five fails to take the grooves, and, secondly, that many of those thus failing explode in the air. The first defect seems to arise partially, though not wholly, from the metallic casing, which has been latterly adopted to prevent the swelling of the papier-mache. This casing I consider should be made less thick, so as not to interfere with the papier-mache, or of material much tougher than zinc, so as to aid the projectile in taking the grooves. The second defect seems to arise from the fact that the centrifugal force, operating on the plungers of those shells which fail to take the grooves, caused the explosion of the caps in air. Any remedy for the first defect will, of course, remedy the second. With the present projectile I do not feel justified in firing over troops, which batteries of position, like those under my command, are always liable to do. I would, therefore, respectfully suggest, in order to remedy this defect, that, during the few days of inactivity which will doubtless follow the late contest, I be allowed to experiment with some other projectile, as, for example, the Hotchkiss shell.
    While I do not underrate the efficiency of fire of the batteries under my command during the late contest, I cannot fail in conclusion to point out the disadvantage to which they were subjected, viz, of firing at troops protected by covers and sunken roads, and the advantages in such cases of using vertical fire.
    With the highest appreciation of the zeal and efficiency of both the officers and men of my command, I have the honor to remain, your obedient servant,

Major First Connecticut Vol. Arty., Comdg. Butt. Conn. Arty