in time will be fully explained, make it expedient, in the general's judgment, that he should retire from this position to the north bank of the Rappahannock for his defensible position. Among these is danger to his communication by possibility of enemy crossing river on our right flank and imperiling this army, with present departure of two-years' and three-months' [nine-months'] troops constantly weakening him. The nature of the country in which we are prevents moving in such a way as to find or judge position or movements of enemy. He may cross to night, but hopes to be attacked in this position.

DANL. BUTTERFIELD,

Major-General, Chief of Staff.

HEADQUARTERS CAVALRY, NEAR PHILLIPS' HOUSE, VA.,
May 5, 1863 - 2.30 p. m. (Received 3.15 p. m.)

Major-General BUTTERFIELD,

Chief of Staff:

Have two regiments of cavalry below Fredericksburg, watching river and Neck over 10 miles down. Hear the rebels did have one pontoon train at Hamilton's Crossing. Have sent for another horse battery to be placed, one at Richards' Ford. Will pounce on them if they try to cross in that way to-night below. Would it not be well for the gun-boats to push up the Rappahannock as far as they can? They can help a great deal. All quiet up to 12 m., at last accounts, up the river and to the rear toward Dumfries.

A. PLEASONTON,

Brigadier-General, Commanding.

HEADQUARTERS CAVALRY,
May 5, 1863 - 3 p. m.

Brigadier-General GIBBON,

Second Division, Second Corps, near Philips' House, Va.:

GENERAL: I am here acting under the direct orders of Major-General Hooker, and am in communication with him. I will all I can to assist you, but my own plans cannot be interfered with. I have a regiment of cavalry at Falmouth guarding the river, but I cannot say at what moment circumstances may induce me to withdraw it to some more important point. My line now extends from Rappahannock Station to below Fredericksburg some 10 or 12 miles, besides to the rear as far as Dumfries. Up to this time the reports are quiet from the right and rear. If the rebels have a pontoon train, they will try to use it below to-night. I will do my best to keep you informed of events.

Very respectfully,

A. PLEASONTON,

Brigadier-General, Commanding.

[Indorsement.]

For the information of General Williams. I should like to be informed whether I am in command of the forces in this vicinity for the defense of the river. One thing is certain, if I am, two persons cannot command the troops.

JOHN GIBBON,

Brigadier-General.