8th of March, threatened serious derangement | quiring immediate compliance with the Presidof the plan for the Peninsula movement. But ent's order, but on my again representing that the engagement between the Monitor and Mer- this would compel the abandonment or postrimack on the 9th of March, demonstrated so ponement of the movement to Manassas, he satisfactorily the power of the former, and the finally consented to its postponement. other naval preparations were so extensive and formidable, that the security of Fort Monroe, as a base of operations, was placed beyond a doubt; and although the James river was closed to us, the York river, with its tributaries, was still open as a line of water communication with the fortress. The general plan, therefore. remained undisturbed, although less promising in its details than when the James river was in our control.

On Sunday, the 9th of March, information from various sources made it apparent that the enemy was evacuating his positions at Centreville and Manassas as well as on the upper and lower Potomac. The President and Secretary of War were present when the most positive information reached me, and I exppressed to them my intention to cross the river immediately, and there gain the most authentic information, prior to determining what course to pursue.

The retirement of the enemy towards Richmond had been expected as the natural consequence of the movement to the Peninsula, but the adoption of this course immediately on ascertaining that such a movement was intended, while it relieved me from the results of the undue anxiety of my superiors, and attested the character of the design, was unfortunate in that the then almost impassable roads between our positions and theirs deprived us of the opportunity for inflicting damage usually afforded by the withdrawal of a large army in the face of a powerful adversary.

The retirement of the enemy and the occupation of the abandoned positions which necessarily followed presented an opportunity for the troops to gain some experience on the march and bivouac preparatory to the campaign, and to get rid of the superfluous baggage and other 'impediments" which accumulate so easily around an army encamped for a long time in one locality.

At noon on the 10th of March the cavalry advance reached the enemy's lines at Centreville, passing through his recently occupied camps and works, and finding still burning heaps of military stores and much valuable property.

Immediately after being assigned to the command of the troops around Washington, I organized a secret service force, under Mr. E. J. Allen, a very experienced and efficient person. This force, up to the time I was relieved from command, was continually occupied in procuring from all possible sources information regarding the strength, positions, and movements of the enemy.

All spies, "contrabands," deserters, refugees, and many prisoners of war, coming into our lines from the front, were carefully examined, first by the outpost and division commanders, and then by my chief of staff and the Provost Marshal General. Their statements, taken in writing, and in many cases under oath, from day to day, for a long period previous to the evacuation of Manassas, comprised a mass of evidence which, by careful digests and colla tions, enabled me to estimate with considerable accuracy the strength of the enemy before us. Summaries showing the character and results of the labors of the secret service force accompany this report, and I refer to them for the facts they contain, and as a measure of the ignorance which led some journals at that time and persons in high office unwittingly to trifle with the reputation of an army, and to delude the country with quaker gun stories of the defences and gross understatements of the numbers of the enemy.

The following orders were issued for the examination of persons coming from the direc tion of the enemy:

["Circular.]

HEADQUARTERS ARMY OF THE Potomac,

A march to Manassas and back would produce no delay in embarking for the lower Ches"Washington, December 16, 1862. apeake, as the transports could not be ready for "The major general commanding directs that some time, and it afforded a good intermediate hereafter all deserters, prisoners, spies, 'constep between the quiet and comparative comfort trabands,' and all other persons whatever comof the camps around Washington, and the rigorsing or brought within our lines from Virginia, of active operations, besides accomplishing the important object of determining the positions and perhaps the future designs of the enemy, with the possibility of being able to harass

their rear.

shall be taken immediately to the quarters of the commander of the division within whose lines they may come or be brought, without previous examination by any one, except so far as may be necessary for the officer commanding I therefore issued orders during the night of the advance guard to elicit information regardthe 9th of March for a general movement of the ing his particular post; that the division comarmy the next morning towards Centreville and mander examine all such persons himself, or Manassas, sending in advance two regiments of delegate such duty to a proper officer of his alry under Colonel Averill with orders to staff, and allow no other persons to hold any reach Manassas if possible, ascertain the exact communication with them; that he then immecondition of affairs, and do whatever he could diately send them. with a sufficient guard, to to retard and annoy the enemy if really in re- the provost marshal in this city for further extreat; at the same time I telegraphed to the amination and safe-keeping, and that stringent Secretary of War that it would be necessary to orders be given to all guards having such perdefer the organization of the army corps until sons in charge not to hold any communication the completion of the projected advance upon with them whatever; and further, that the Manassas, as the divisions could not be brought information elicited from such persons shall be together in time. The Secretary replied, re-immediately communicated to the major general

commanding, or to the chief of staff, and to no other person whatever.

About three hundred field guns and from twenty-six to thirty siege guns were with the "The major general commanding further rebel army in front of Washington. The redirects that a sufficient guard be placed around port made on the 17th of March, after the every telegraph station pertaining to this army, evacuation of Manassas and Centreville, corand that such guards be instructed not to allow roborates the statements contained in the report any person, except the regular telegraph corps, of the 8th, and is fortified by the affidavits of general officers, and such staff officers as may several railroad engineers, constructors, bagbe authorized by their chief, to enter or loiter gage-masters, &c., whose opportunities for formaround said stations within hearing of the sound ing correct estimates were unusually good. of the telegraph instruments. These affidavits will be found in the accom"By command of Major Gen. MCCLELLAN.panying reports of the chief of the secret service corps.

"S. WILLIAMS,
"Assistant Adjutant General."

'HEADQUARTERS ARMY OF THE POTOMAC,
"Washington, February 26, 1862.

"GENERAL Order

No. 27.

A reconnoissance of the works at Centreville made by Lieutenant McAlester, United States engineers, on March 14, 1862, and a survey of those at Manassas, made by a party of the United States coast survey, in April, 1862, confirmed also my conclusions as to the strength of the enemy's defences. Those at Centreville consisted of two lines, one facing east and the other north. The former consisted of seven *works, viz: one bastion fort, two redoubts, two lunettes, and two batteries; all containing embrasures for forty guns, and connected by infantry parapets and double caponieres. extended along the crest of the ridge a mile and three quarters from its junction with the northern front to ground thickly wooded and impassable to an attacking column.

It

"All deserters from the enemy, prisoners, and other persons coming within our lines, will be taken at once to the provost marshal of the nearest division, who will examine them in presence of the division commander or an officer of his staff designated for the purpose. This examination will only refer to such information as may affect the division and those near it. especially those remote from general head-one-fourth mile to Great Rocky run, and thence three-fourths of a mile further to thickly wooded, quarters.

The northern front extended about one and

"As soon as this examination is completed- impassable ground in the valley of Cub run. and it must be made as rapidly as possible-It consisted of six lunettes and batteries with the person will be sent, under proper guard, to embrasures for thirty-one guns, connected by the Provost Marshal General, with a statement an infantry parapet in the form of a cremailAt the town of Centreof his replies to the questions asked. Upon lere line with redans. receiving him, the Provost Marshal General ville, on a high hill commanding the rear of will at once send him, with his statement, to all the works within range, was a large hexthe chief of staff of the army of the Potomac, agonal redoubt with ten embrasures. who will cause the necessary examination to be made. The Provost Marshal General will have the custody of all such persons. Division commanders will at once communicate to other division commanders all information thus obtained which affects them.

*

*

"By command of Major Gen. MCCLELLAN.
"S. WILLIAMS,
"Assistant Adjutant General."

In addition to the foregoing orders, the division commanders were instructed, whenever they desired to send out scouts towards the enemy, to make known the object at headquarters, in order that I might determine whether we had the information it was proposed to obtain, and that I might give the necessary orders to other commanders, so that the scouts should not be molested by the guards.

It will be seen from the report of the chief of the secret service corps, dated March 8, that the forces of the rebel army of the Potomac, at that date, were as follows:

At Manassas, Centreville, Bull run, Upper
Occoquan, and vicinity......

At Brooks's station, Dumfries, Lower Occo-
quan, and vicinity

At Leesburg and vicinity

In the Shenandoah valley..

80,000 men.

Manassas station was defended in all directions by a system of detached works, with platforms for heavy guns arranged for marine carriages, and often connected by infantry parapets. This system was rendered complete by a very large work, with sixteen embrasures, which commanded the highest of the other works by about fifty feet.

Sketches of the reconnoissances above referred to will be found among the maps appended to this report.

From this it will be seen that the positions selected by the enemy at Centreville and Manassas were naturally very strong, with impassable streams and broken ground, affording ample protection for their flanks, and that strong lines of intrenchments swept all the available approaches.

Although the history of every former war has conclusively shown the great advantages which are possessed by an army acting on the defensive and occupying strong positions, defended by heavy earthworks; yet, at the commencement of this war, but few civilians in our country, and, indeed, not all military men of rank, had a just appreciation of the fact.

New levies that have never been in battle cannot be expected to advance without cover 18,000 men. 4,500 men. under the murderous fire from such defences, 18,000 men. and carry them by assault. This is work in which veteran troops frequently faulter and are 115,500 men. repulsed with loss. That an assault of the

enemy's positions in front of Washington, with the new troops composing the army of the Potomac, during the winter of 1861-'62, would have resulted in defeat and demoralization, was too probable.

saw fit to make of my services, and so informed him in a note on the 12th of March, in which occur these words:

"I believe I said to you some weeks since, in connection with some western matters, that The same army, though inured to war in no feeling of self-interest or ambition should many battles, hard fought and bravely won, ever prevent me from devoting myself to the has twice, under other generals, suffered such service. I am glad to have the opportunity to disasters as it was no excess of prudence then prove it, and you will find that, under present to avoid. My letter to the Secretary of War, circumstances, I shall work just as cheerfully dated February 3, 1862, and given above, ex- as before, and that no consideration of self will pressed the opinion that the movement to the in any manner interfere with the discharge of Peninsula would compel the enemy to retire my public duties. Again thanking you for the from his position at Manassas and free Wash-official and personal kindness you have so often ington from danger. When the enemy first evinced towards me, I am," &c., &c. learned of that plan, they did thus evacuate Manassas. During the Peninsula campaign, as at no former period, northern Virginia was completely in our possession, and the vicinity of Washington free from the presence of the enemy. The ground so gained was not lost, nor Washington again put in danger, until the enemy learned of the orders for the evacuation of the Peninsula, sent to me at Harrison's bar, and were again left free to advance northward and menace the national capital. Perhaps no one now doubts that the best defence of Washington is a Peninsula attack on Richmond.

My order for the organization of the army corps was issued on the 13th of March; it has been given above.

While at Fairfax Court-house, on March 12, I was informed through the telegraph, by a member of my staff, that the following document had appeared in the National Intelligencer of that morning:

[President's War Order, No. 8.]

"EXECUTIVE MANSION,

"Washington, March 11, 1862. "Major General McClellan having personally taken the field at the head of the army of the Potomac, until otherwise ordered, he is relieved from the command of the other military departments, he retaining command of the department of the Potomac.

"Ordered further, That the departments now under the respective commands of Generals Halleck and Hunter, together with so much of that under General Buell as lies west of a north and south line indefinitely drawn through Knoxville Tennessee, be consolidated and designated the department of the Mississippi; and that, until otherwise ordered, Major General Halleck have command of said department.

On the 14th of March a reconnoissance of a large body of cavalry with some infantry, under command of General Stoneman, was sent along the Orange and Alexandria railroad to determine the position of the enemy, and, if possible, force his rear across the Rappahannock, but the roads were in such condition that, finding it impossible to subsist his men, General Stoneman was forced to return after reaching Cedar run.

The following despatch from him recites the result of this expedition:

* HEADQUARTERS, UNION MILLS,
"March 16, 1862.

Felt

"We arrived here last evening about dark. We got corn for horses; no provisions for men. Bull run too high to cross. Had we stayed an hour longer we should not have got here to-day, owing to the high water in the streams. the enemy cautiously, and found him in force at Warrenton Junction. Saw two regiments of cavalry and three bodies of infantry on the other side of Cedar run. Had we crossed, should not have been able to get back for high water. Had three men of 5th cavalry hit driving in enemy's pickets; one slightly wounded in the head. Enemy acted confidently, and followed us some way back on the road, but did not molest us in any way. Enemy's force consisted of Stuart's and Ewell's cavalry, a battery of artillery and some infantry. Railroad bridges all burned down up to Warrenton Junction; still entire beyond, but all in readiness to burn at a moment's warning, having dry wood piled upon them. Heard cars running during night before last; probably bringing up troops from Rappahannock. Heard of two regiments of infantry at Warrenton engaged in impressing the militia and securing forage. Heard of a large force of infantry this side of Rappahannock river, having come up to Warrenton Junction from Aquia creek day before yesterday. Bridges all deThe aides who

"Ordered also, That the country west of the department of the Potomac and east of the department of the Mississippi be a military department, to be called the mountain depart-stroyed this side of Broad run. ment, and that the same be commanded by take this will give you further particulars. Major General Fremont. "Very respectfully, &c.,

That all the commanders of departments, after the receipt of this order by them, respectively report severally and directly to the Secretary of War, and that prompt, full, and frequent reports will be expected of all and each

of them.

"ABRAHAM LINCOLN."

Though unaware of the President's intention to remove me from the position of general-inchief, I cheerfully acceded to the disposition he

"GEORGE STONEMAN, “Brigadier General, Commanding.

"Col. COLBURN."

The main body of the army was, on the 15th of March, moved back to the vicinity of Alexandria to be embarked, leaving a part of General Sumner' corps at Manassas until other Before it troops could be sent to relieve it. was withdrawn a strong reconnoissance, under

General How ard, was sent towards the Rappa- (suffice. (Keys, Heintzelman, and McDowell) hannock, the result of which appears in the A total of 40.000 men for the defence of the following despatch: city would suffice. (Sumner)."

WARRENTON JUNCTION,

"March 29, 1862.

This was assented to by myself, and immediately communicated to the War Department The following reply was received the same

"Express just received from General How-day: ard. He drove the enemy across the Rappahannock bridge, and.is now in camp on this bank of and near the Rappahannock river.

"The enemy blew up the bridge in his re-
treat. There was skirmishing during the march,
and a few shots exchanged by the artillery;
without any loss on our side. Their loss, if
any, is not known.
not known. General Howard will re-
turn to this camp to-morrow morning.

"E. V. SUMNER,
"Brigadier General.

"HEADQUARTERS ARMY OF THE POTOMAC,

"Fairfax Court-house, March 13, 1862.

"A council of the generals commanding army corps, at the head-quarters of the army of the Potomac, were of the opinion

"WAR DEPARTMENT, March 13, 1862. of operations agreed upon by yourself and the "The President having considered the plan to the same, but gives the following directions commanders of army corps, makes no objections

as to its execution:

"1. Leave such force at Manassas Jnnction as shall make it entirely certain that the enemy shall not repossess himself of that position and line of communication.

"2. Leave Washington entirely secure.

"3. Move the remainder of the force down the Potomac, choosing a new base at Fortress Monroe, or anywhere between here and there, or, at all events, move such remainder of the army at once in pursuit of the enemy by some

route.

"EDWIN M. STANTON, "Secretary of War. "Major General GEORGE B. McClellan.”

My preparations were at once begun in accordance with these directions, and on the 16th of March the following instructions were sent to Generals Banks and Wadsworth:

HEADQUARTERS ARMY OF THE POTAMAC,

"March 16, 1862.

"I. That the enemy having retreated from Manassas to Gordonsville, behind the Rappahannock and Rapidan, it is the opinion of the generals commanding army corps that the operations to be carried on will be best undertaken from Old Point Comfort, between the York and James rivers: Provided, "1st. That the enemy's vessel, Merrimac, cantions with the valley of the Shenandoah. be neutralized.

"SIR: You will post your command in the vicinity of Manassas, intrench yourself strongly, and throw cavalry pickets well out to the front.

"2d. That the means of transportation, sufficient for an immediate transfer of the force to its new base, can be ready at Washington and Alexandria to move down the Potomac; and, "3d. That a naval auxiliary force can be had to silence, or aid in silencing, the enemy's batteries on the York river.

"Your first care will be the rebuilding of the railway from Washington to Manassas and to Strasburg, in order to open your communica

A8

soon as the Manassas Gap railway is in running order, intrench a brigade of infantry, say four regiments, with two batteries, at or near the point where the railway crosses the Shenandoah. Something like two regiments of cavalry should be left in that vicinity to occupy ester and thoroughly scour the country south of the railway and up the Shenandoah valley, as well as "4th. That the force to be left to cover Wash- through Chester gap, which might perhaps be Wash-through ington shall be such as to give an entire feeling advantageously occupied by a regiment of inof security for its safety from menace. (Unan- fantry, well intrenched. Block-houses should imous). be built at all the railway bridges.' Occupy by grand guards Warrenton Junction and Warrenton itself and also some little more advanced point on the Orange and Alexandria railroad, as soon as the railway bridge is repaired.

II. If the foregoing cannot be, the army should then be moved against the enemy, behind the Rappahannock, at the earliest possible moment, and the means for re-constructing bridges, repairing railroads, and stocking them with materials sufficient for supplying the army, should at once be collected, for both the Orange and Alexandria and Aquia and Richmond railroads. (Unanimous).

"N. B.-That with the fort on the right bank of the Potomac fully garrisoned, and those on the left bank occupied, a covering force in front of the Virginia line of 25.000 men would

"Great activity should be observed by the cavalry. Besides the two regiments at Manassas, another regiment of cavalry will be at your disposal, to scout towards the Occoquan, and probably a fourth towards Leesburg.

"To recapitulate, the most important points which should engage your attention are as follows: