HEADQUARTERS ENGINEER BRIGADE,
Near Fredericksburg, Va., December 12, 1862.

GENERAL: I have the honor to report the operations of the Engineer Brigade in throwing bridges over the Rappahannock on the 11th instant.

In obedience to the orders of the commanding general, four bridge <ar31_170> trains were taken to the banks of the river at 3 o'clock on the morning of that day, preparatory to the construction of two bridges at the rope ferry, above the center of the town; one bridge opposite the lower end of the town; one bridge about 1 mile below the town.

All these bridges were commenced soon after 3 o'clock, supported each by a regiment of infantry, placed under the cover of the adjacent low banks, and by numerous batteries of light and heavy guns, planted upon the crests, near the river.

The low bridge, under Major Magruder, Fifteenth Regiment New York Volunteers, was completed, all but the last lay, at 8.15 a.m., when a volley from the enemy wounded 5 of the men, and caused for the time a suspension of the work. The enemy, having no shelter, was soon dispersed by our artillery. The bridge was resumed and finished at 9 a.m., under the immediate superintendence of Lieutenant Slosson. The Fifteenth Regiment afterward assisted in completing the other bridges.

The lower town bridge and one of the upper ones, under Major Spaulding, Fiftieth Regiment New York Volunteers, were about two-thirds built at 6 a.m., when the enemy, availing himself of every possible cover, commenced a strong fire of musketry upon the pontoniers and the infantry supports. Captain Perkins, a fine officer of the Fiftieth Regiment, was instantly killed. Captains Brainerd and McDonald, both excellent officers, and many privates, were soon afterward wounded and disabled. Our artillery tried in vain to silence this fire, a dense fog making it impossible to distinguish objects on the opposite shore. The work was resumed several times during the morning, without making much further progress.

About 10 o'clock, I led 80 volunteers from the Eighth Connecticut, under Captain Marsh, Lieutenant Ford, and Lieutenant Morgan, to the scene of operations, placing one-half of them under cover as a reserve. Before the other half touched the bridge, several of them were shot down, and the remainder refused to work. The fog clearing up soon after noon, our artillery fire upon the opposite banks became very effective, and the fire of the enemy was greatly diminished.

About 3 o'clock, preparations were made for sending over men in pontoons, in accordance with the advice of General Hunt.

After another heavy cannonading, about 120 men of the Seventh Michigan, Hall's brigade, crossed over at the upper bridge in six pontoons, rowed each by three men of the Fiftieth, Lieutenant Robbins steering the leading boat to the point indicated. One of the oarsmen in this boat was shot down, and the boat was, for a short time, arrested. A few other casualties occurred while the men were passing over. As soon as they reached the opposite bank, they formed, and gallantly rushed to the buildings occupied by the enemy, and took some prisoners. Other parties rapidly followed, and the bridges were finished without further opposition. Soon afterward, 100 men of the Eighty-ninth New York crossed at the lower town bridge in four pontoons provided by Major Magruder, with crews from the Fifteenth New York. Others followed, and the sharpshooters of the enemy who still remained were immediately captured. The bridge was soon afterward finished.

I was greatly mortified in the morning to find that the pontoniers under my command would not continue at work until actually shot down. The officers and some of the men showed a willingness to do so, but the majority seemed to think their task a hopeless one. Perhaps I was unreasonable.

It is generally considered a brave feat to cross a bridge of any length under fire, although the time of danger may not last more than a minute <ar31_171> or two. How much more difficult to build a bridge exposed for hours to the same murderous fire, the danger increasing as the bridge is extended.

I found a loop-holed block-house, uninjured by our artillery, directly opposite our upper bridges, and only a few yards from their southern abutment. I also found in the neighborhood a rifle-pit behind a stone wall, some 200 feet long, and cellars inclosed by heavy walls, where the enemy could load and fire in almost perfect safety. There were many other secure shelters.

During the night of the 10th and 11th, between sunset and 2 o'clock, a corduroy road 1,000 feet long was laid by the Fourth Maine, under the superintendence of Lieutenant Van Brocklin, Fiftieth New York, at a point on the river about 14 miles below town. This ruse seems to have been very effective in deceiving the enemy.

The officers of my staff, Capt. H. W. Bowers, Lieutenants Cassin and Hassler, and Captain Hine, Fiftieth New York, a volunteer aide for the time, were untiring during the night and day, going wherever duty called them, regardless of danger.

I inclose the reports of Major Magruder, commanding the Fifteenth New York, and of Major Spaulding, commanding a detachment of six companies of the Fiftieth New York. These highly efficient officers discharged their duties with great energy. They give more detailed accounts of the operations.

From personal observation, I am able to confirm Major Spaulding in praising the conduct of Captains Brainerd and Ford, and Lieutenants Robbins, Folley, and Palmer. Captain McDonald and Lieutenants McGrath and Dexter are also deservedly praised.

Besides the bridges above mentioned, one was built by the regular Sappers and Miners, under Lieutenant Cross, on the 11th instant, and another has since been built by the Fifteenth New York, a mile below the town, so that six bridges in good order now span the river. The three opposite the town are each 400 feet long. One of those below the town is also 400 feet 1ong; one 420 feet, and one 440 feet.

In conclusion, I take pleasure in acknowledging the assistance of Lieutenant Comstock, chief engineer. He came upon the ground at a critical moment, when the first detachment of infantry had embarked to cross over, and gave a strong helping hand in urging and inducing others to follow.

I send herewith the official reports of the killed and wounded of the Engineer Brigade in the action of the 11th instant, amounting to 50 in all.(*)

Very respectfully,

D. P. WOODBURY,

Brigadier-General of Volunteers

Maj. Gen. J. G. PARKE,

Chief of Staff, Army of the Potomac.

KEY WEST, December 21, 1863.

MY DEAR GENERAL: I have read your interesting report of military operations during the past year, and I wish to thank you for all you have said incidentally relative to myself in connection with Burnside's operations at Fredericksburg. <ar31_172>

I could not fully exculpate myself without demonstrating that my commanding officer, General Burnside, was in fault. The narrative of facts proved this, but some of my friends did not understand the matter and have never been satisfied with my record.

Your clear and explicit statement removes all obscurity and doubt, and I am naturally much gratified. My vindication at your hands is the more gratifying because my own testimony before the Congressional committee was construed in some of the newspapers as imputing fault to you. When I first met Burnside at Fredericksburg, and was asked to explain why pontoons were not at hand when the army arrived, I told him that he commenced his movement before he was ready ; that he ought to have remained at Warrenton some five days longer; and I added, to show that the idea was not new to me, "I told Halleck so." It never occurred to me to say anything about this conversation to the committee, nor did I do so, or even think of it, until one of them drew it out by a direct question. I then seemed, to a careless reader of the record, to desire to throw some blame upon you.

Changing the subject, it seems to me that the rebels have not made, during the past season, all the use of their interior lines which they might have made. In June they undertook two principal operations: First, to invade Maryland and Pennsylvania; second, to oppose Rosecrans with an army nearly equal to his own. Had the army of Bragg been added to that of Lee, the latter might, perhaps, have gained the battle of Gettysburg, and that would have compelled us to withdraw the army of Rosecrans for the defense of Washington. On the other hand, had the army of Lee been added to that of Bragg, Rosecrans might, perhaps, have been overwhelmed far from his base. Too late they attempted the right thing. After losing the use of the railroad connecting Virginia with Chattanooga, after Rosecrans had secured an impregnable position (Chattanooga) to fall back upon in case of defeat, they began to re-enforce Bragg by the very circuitous route of Atlanta, and then gained a battle with very little advantage to themselves.

If the enemy has sometimes been superior in tactics, I think he has been beaten in strategy throughout the year, and it will be hard to rob the General-in-Chief of a principal share of the credit.

Truly, yours,

D. P. WOODBURY.

Maj. Gen. H. W. HALLECK,

General-in-Chief, Washington, D. C.