[Inclosure.]

OFFICE PROVOST-MARSHAL-GENERAL, April 22, 1863.

Brigadier General S. WILLIAMS,

Assistant Adjutant-General, Army of the Potomac:

GENERAL: I have the honor to report that on yesterday I made an examination in person of the picket lines along the river from Snowdon up to town, with special reference to the subject of the communication from Major Jenckes.

I learn at Mrs. Seddon's and Mrs. Gray's that the withdrawal of the cavalry was noticed by the families when they rose in the morning, and that such withdrawal was apparently noticed from the other side, as the Confederates had our cavalry pickets and some of the reserves in full view. I understood that several officers of Confederates in the early part of the day rode down the lines, apparently to see what changes had taken place. I find, from the persons living along the river, from servants, and from certain men of my own, posted along two or three points in the vicinity of the picket line, that communications are kept up between the pickets across the river much of the time. These informants do not like to say much about it, for fear of the consequences to themselves from the parties of whom they speak.

From April 9 to the 12th, Lieutenant Castle Sixty-second New York Volunteers, had command of the pickets, and during that time both he and his men had frequent conversations with the enemy's pickets by means of small sail-boats, the lieutenant assisting in rigging boats, and both night and day had conversation with them. The day before the lieutenant was relieved, I went down to the river and took a boat which had been used to send across the river, up to Morsson's house, and broke it up. The lieutenant asked me what business I had to break the boat. He said he had sent sugar in return.

On the night of the 15th a conversation was carried on near Dr. Morsson's house, after 9 o'clock, between the pickets of the One hundred and sixty-ninth Pennsylvania Volunteers and the rebels. The first part of the conversation was about rations. Secesh them asked, "Any signs of a move?" We have three days' rations in our haversack and five in our knapsacks." Secesh then asked, " Where is the move to be? Reply, "Up to the night." Secesh then asked how we were going to get transportation, or whether we would hold the railroad. Our picket replied that he thought the trains would be kept up by pack-mules. This ended the conversation. Has know of no conversation since the 15th instant between the pickets; had there been, should have known it.

The above is from a statement made me by Private Collins, Eighth Regulars, one of my own men on duty at and near Dr. Morsson's, corroborated by the doctor himself.

The visit of Surgeon Wyncoop to Mr. Pollock's was, as I understand, on the morning of the 14th, the cavalry pickets having been withdrawn on the 13th and an infantry guard from the Eighth sent down to Snowdon the same day, on the application of the signal officer, after the cavalry left. If this be so, Major Jenckes is in error as to the manner in which information of the cavalry move was obtained.

I may add that I have frequently made reports of the irresponsible manner in which picket duty is performed from some 4 or 5 miles down the river, but from the fact, I suppose, that these reports generally grew out of complaints made by citizens, the conduct of the company and regimental officers has not, in my opinion, received the attention demanded.

Very respectfully, your obedient servant,

M. R. PATRICK,

Provost-Marshal-General.