The reference to the Monitor is to be explained by the condition previously made in connection with the proposition of going to Fortress Monroe, that the Merrimac, our Virginia, should first be neutralized. The order to bring the "transports" to Washington was due to the fact that they had not dared to run by our batteries on the Potomac, and intended to avoid them by going to Annapolis for embarkation. The withdrawal of our batteries from the banks of the Potomac had removed the objection to going down that river, and the withdrawal of our forces across the Rappahannock was fatal to the programme of landing on that river, and marching to Richmond before our forces could be in position to resist an attack on the capital. Notwithstanding the assurance given that the destruction of railroads and bridges proved that our army could not intend to advance, apprehension was still entertained of an attack upon Washington.
As soon as we ascertained that the enemy was concentrating his forces at Fortress Monroe, to advance upon our capital by that line of approach, all our disposable force was ordered to the Peninsula, between the James and York Rivers, to the support of General John B. Magruder, who, with a force of seven to eight thousand men, had, by availing himself of the Warwick River, a small stream which runs through a low, marshy country, from near Yorktown to the James River, constructed an intrenched line across the Peninsula, and with equal skill and intrepidity had thus far successfully checked every attempt to break it, though the enemy was vastly superior in numbers to the troops under General Magruder's command. Having a force entirely inadequate to occupy and defend the whole line, over thirteen miles long, he built dams in the Warwick River, so as to form pools, across which the enemy, without bridges, could not pass, and posted detachments at each dam to prevent the use of them by attacking columns of the enemy. To defend the left of his line, where the stream became too small to present a serious obstacle to the passage of troops, redoubts were constructed, with curtains connecting them.
Between Yorktown and Gloucester Point, on the opposite shore, the York River is contracted to less than a mile in width, and General Magruder had constructed batteries at both places, which, by their cross fire, presented a formidable obstacle to the accent of ordinary vessels. The fortifications at Norfolk and the navy-yard, together with batteries at Sewell's Point and Craney Island, in conjunction with the navy, offered means of defense against any attempt to land troops on the south side of James River. After the first trial of strength with our Virginia, there had been an evident disinclination on the part of the enemy's vessels to encounter her, so that, as long as she floated, the deep water of the roads and mouth of James River. was not likely to be invaded by ships of war.
As a second line of defense, a system of detached works had been constructed by General Magruder near to Williamsburg, where the width of the Peninsula, available for the passage of troops, was only three or four miles. The advantage thus secured to his forces, if they should be compelled to retreat, will be readily appreciated. I am not aware that torpedoes had been placed in York River to prevent the entrance of the enemy's vessels; indeed, at that time, but little progress had been made in the development of that means of harbor and river defense. General Rains, as will be seen hereafter, had matured his invention of sensitive fuse-primers for sub-terra shells, and proposed their use for floating torpedoes. Subsequently he did much to advance knowledge in regard to making torpedoes efficient against the enemy's vessels.
Such was the condition of the Virginia Peninsula between the York and James Rivers when General McClellan embarked the mass of the army he commanded in northern Virginia and proceeded to Fortress Monroe; and when the greater part of our army, under the command of General J. E. Johnston, was directed to move for the purpose of counteracting this new plan of the enemy.
Early in April, General McClellan had landed about one hundred thousand men at or near Fortress Monroe.[21] At this time General Magruder occupied the lower Peninsula with his force of seven or eight thousand men. Marshes, creeks, and dense wood gave to that position such advantage that, in his report, made at a subsequent period, he expressed the belief that with twenty or twenty-five thousand men he could have held it against any supposable attack. When McClellan advanced with his immense army, Magruder fell back to the line of Warwick River, which has been imperfectly described, and there checked the enemy; and the vast army of invasion, repulsed in several assaults by the most heroic conduct of our troops, commenced a siege by regular approaches. After the first advance of the enemy, General Magruder was reënforced by some troops from the south side of James River and General Wilcox's brigade, which had been previously detached from the army under General Johnston. On the 9th of April General Magruder's command, thus reënforced, amounted to about twelve thousand. On that day General Early joined with his division from the Army of Northern Virginia. It had gone by rail to Richmond and thence down the York and James Rivers in vessels towed by tugs—except the trains and artillery, which moved by land. This division had about eight thousand officers and men for duty. General Magruder's force was thus increased to about twenty thousand. This was the first detachment from the Army of Northern Virginia which arrived on the Peninsula.
General McClellan, in a cipher dispatch of the 7th of April, two days previous, informed Secretary Stanton that prisoners stated that General J. E. Wharton (no doubt, Johnston) had the day before arrived in Yorktown with strong reënforcements, and adds: "It seems clear that I shall have the whole force of the enemy on my hands, probably not less than one hundred thousand men, and possibly more. . . . When my present command all joins, I shall have about eighty-five thousand men for duty, from which a large force must be taken for guards, escort, etc." After some remarks about the strength of our intrenchments, and his conviction that the great battle which would decide the existing contest would be fought there, he urges as necessary for his success that there should be an attack on the rear of Gloucester Point, and adds: "My present strength will not admit of a detachment for this purpose without materially impairing the efficiency of this column. Commodore Goldsborough thinks the work too strong for his available vessels, unless I can turn Gloucester." [22]
In the cipher dispatch of the 7th of April to President Lincoln, General McClellan acknowledges a telegram of the previous day, and adds, "In reply, I have the honor to state that my entire force for duty only amounts to about eighty-five thousand men." [23] He then mentions the fact that General Wool's command is not under his orders, etc.
Subsequent correspondence clearly shows that General McClellan would not risk making a detachment from his army to turn the position at Gloucester Point, and that the navy would not attempt to operate against the battery at that place. He therefore urgently pressed for reënforcements to act on the north side of York River.
General Magruder had, up to and after the time of receiving the reënforcements before mentioned, worked day and night in constructing and strengthening his defenses. His small force had been assisted in this work by a considerable body of negro laborers, and an active participant and competent judge, General Early, thus wrote of his conduct: