I received a special order directing me to assume command of this district. I presumed that General Peck had been notified of this order, but as during the whole of yesterday, 21st instant, General Peck had not intimated to me any knowledge of the order, I thought it proper to inclose him a copy of it, and in a conversation which I have had with his this day he has declared his readiness to turn over the command.

You have probably before this time received General Peck's dispatch announcing the capture of plymouth with its garrison on the 20th instant. The rebels will either hold it or evacuate it. If they attempt to hold it, I shall make no attempt to recapture it at present, and if they evacuate it, I shall not re-establish a post there at present. The mouth of the Roanoke River will be held by our gunboats, and I am of the opinion that the rebel ram, which has been the principal cause of the fall of plymouth, will not be able to get out into the sounds.

It is my impression that the success of the attack upon Plymouth will induce the rebels to attack Little Washington. That place has in it a respectable force, and will, I think, be able to resist any attack, although I do not consider the garrison sufficiently large if it be attacked by the force that has captured Plymouth. At present, however, no further re-enforcements can be sent to that place from here. At this place, exclusive of the outposts, the troops for its defense consist only of the garrisons of the different forts, with five companies of infantry (white) and a portion (250 men) of the Twenty-fifth Regiment U. S. Colored Troops, all the other troops having been sent to re-enforce either Washington, Plymouth, or Roanoke Island. I do not consider that it was necessary to re-enforce Roanoke Island, and i shall therefore withdraw the re-enforcements that were sent to that place by General Peck's order, and order them again to this place.

The rebels are making every preparation to bring the ram, which has been for some time at Kinston, down the river. I am kept constantly advised of the progress of the work upon it. She is completed and a few days since a party wa sent by the rebels to sound the channel, coming as low down as the blockade which we have constructed. The work upon this blockade is punched day and night, and it will be made as effectual as possible. It is under the fire of several heavy guns and carefully watched.

The First U. S. Colored Troops will be forwarded to Fortress Monroe at the earliest possible moment. The steamers that leave to-night will probably return with that portion of the regiment that went to Roanoke by the morning of the 24th instant. The Twenty-third New York Battery will also be withdrawn from Washington and sent to Fortress Monroe at the earliest possible moment.

I regret that I can give no particulars of the affair at plymouth. Colonel Dutton, chief of staff to General Peck, who returned from the moth of the Roanoke yesterday, informed me that he heard from persons who had escaped that our casualties were small; that the defense was vigorous; that the garrison made prisoners had been sent away, but that General Wessells was on parole in the town.

I am, major, very respectfully, your obedient servant,

I. N. PALMER,

Brigadier-General.

Major R. S. DAVIS,

Asst. Adjt. General, Dept. of Virginia and North Carolina.