order of battle. Our object seemed to be accomplished, for it was not until late in the evening that he advanced, feeling his way cautiously, and making no assault, invested our defenses. My scouts had reported two corps d'armee in front of us (the Thirteenth and Sixteenth), Major-General Canby commanding. From information derived from the prisoners, and from drawings and maps captured with one of the engineers of the Sixteenth Corps, I estimated the force to be not less than 20,000 muskets strong; perhaps much larger. On his first advance the succeeded at some points in pushing his skirmishers to within 200 yards; on the center and right he was driven back. Our artillery fire was reserved until his light batteries came well up, when it was suddenly opened, and it appeared to be with decided effect. On the left the ground wa more favorable to the enemy, and to this fact and the want of works may be ascribed the nearness with which he was enabled to establish himself. On the right and center he was held at bay to the very close of the operations, nor did he at any time gain any decided advantage without severe contests and heavy losses. He sat down before us and developed rapidly a system of regular approaches by parallels. He gradually converted his advanced lines into heavy works, and after the first week displayed an exceedingly large armament of artillery. The absolute necessity of first completing our lines and the smallness of my force prevented the attempt to meet his approaches by any system of advance. There was a great deficiency of tools. Spades, axes, and every available instrument that could be of service in any way, were kept busy night and day from the commencement to the close.
In the first days of the investment (the third, I believe) Thomas' brigade of Alabama Reserves was relieved by Holtzeclaw's and Ector's brigades, both together exceeding Thomas's by about 100 muskets. Large detachments from these commands did not rejoin them. While the transfer was being made my force was greatly swollen, but the troops were for the most part out of position awaiting transportation. Sickness and constant heavy details diminished the number of muskets. For the first ten days my artillery, aided by well-trained sharpshooters, was able to cope with that of the enemy, sometimes silencing his guns, and often broke up his working parties in handsome style; but after this time it was evident, from his overwhelming resources in men and guns, that it would be impossible with the means at my disposal to arrest his gradual advance. While he was steadily digging up to our front and flanks, his fleet kept up a well-directed and heavy fire in our rear, and mortars dropped over the entire surface shells of the largest size; his batteries in rear of his right flank bombarded Batteries Huger and Tracy, exposing our communication, and sweeping the woody flat upon the left flank, enfiladed for several hundred yards that part of the line, and took in reverse-the center and right-the batteries and rifle-pits, so his batteries in front of Redoubt McDermott, No. 2, looked down upon our whole right, and took in reverse the left center and left. Our works were shaped a good deal like a horseshoe pressed open, and those batteries at the toe and heels could command every part of the line, and these batteries were of the weightiest metal. An expedition between us and Blakely in Bay Minette was daily growing more formidable, and it became necessary to guard our water flanks by picket-boats, and to dispose a considerable force to protect our rear and the telegraph lines and the headway against fleet and barges. Several attempts were made by concentrated bombardment from day to day to demoralize the troops, with the intention to take advantage of any accident,