On December 5, General D. H. Hill, with some of his field guns, assisted by Major Pelham, of Stuart's Horse Artillery, attacked the gunboats at Port Royal and caused them to retire. With these exceptions, no important movement took place, but it became evident that the advance of the enemy would not be long delayed. The interval was employed in strengthening our lines, extending from the river about 1 1/2 miles above Fredericksburg along the range of hills in the rear of the city to the Richmond railroad. As these hills were commanded by the opposite heights in possession of the enemy, earthworks were constructed upon their crest at the most eligible positions for artillery. These positions were judiciously chosen and fortified, under the direction of Brigadier-General Pendleton, chief of artillery; Colonel Cabell, of McLaws' division; Colonel E. P. Alexander, and Captain S. R. Johnston, of the engineers. To prevent gunboats from ascending the river, a battery, protected by intrenchments, was placed on the bank, about 4 miles below the city, in an excellent position, selected by my aide-de-camp, Major [T. M. R.] Talcott. The plain of Fredericksburg is so completely commanded by the Stafford Heights that no effectual opposition could be made to the construction of bridges or the passage of the river without exposing our troops to the destructive fire of the numerous batteries of the enemy. At the same time the narrowness of the Rappahannock, its winding course, and deep bed presented opportunities for laying down bridges at points secure from the fire of our artillery. Our position was, therefore, selected with a view to resist the enemy's advance after crossing, and the river was guarded only by a force sufficient to impede his movements until the army could be concentrated.

Before dawn, on December 11, our signal guns announced that the enemy was in motion. About 2 a. m. he commenced preparations to throw two bridges over the Rappahannock, opposite Fredericksburg, and one about 1 1/4 miles below, near the mouth of Deep Run. Two regiments of Barksdale's brigade, McLaws' division (the Seventeenth and Eighteenth Mississippi), guarded these points; the former, assisted by the Eighth Florida, of Anderson's division, being at the upper. The rest of the brigade, with the Third Georgia Regiment, also of Anderson's division, was held in reserve in the city. From daybreak until 4 p. m. the troops, sheltered behind the houses on the river bank, repelled the repeated efforts of the enemy to lay his bridges opposite the town, driving back his working parties and their supports with great slaughter. At the lower point, where there was no such protection, the enemy was successfully resisted until nearly noon, when, being greatly exposed to the fire of the batteries on the opposite heights and a superior force of infantry on the river bank, our troops were withdrawn, and about 1 p. m. the bridge was completed.

Soon afterward, one hundred and fifty pieces of artillery opened a furious fire upon the city, causing our troops to retire from the river bank about 4 p. m. The enemy then crossed in boats and proceeded rapidly to lay down the bridges. His advance into the town was bravely resisted until dark, when our troops were recalled, the necessary time for concentration having been gained.

During the night and the succeeding day the enemy crossed in large numbers at and below the town, secured from material interruption by a dense fog. Our artillery could only be used with effect when the occasional clearing of the mist rendered his columns visible. His batteries on the Stafford Heights fired at intervals upon our position. Longstreet's corps constituted our left, with Anderson's division resting upon the river, and those of McLaws, Pickett, and Hood extending to the