SANDY HOOK, Md., June 17, 1863-11 a. m.

Major-General SCHENCK,

Baltimore, Md.:

The two regiments (Fourteenth New Jersey and One hundred and thirty-eight Pennsylvania) are on Maryland Heights. I am arranging to scour the country thoroughly, and have cavalry enough to do it. A boatman, who left Williamsport at 2 p. m. yesterday, says there is a strong rebel force at Williamsport. Infantry and cavalry destroying the canal and trying to blow up the aqueduct.

DAN. TYLER,

Brigadier-General.

FIELD ORDERS, Numbers 1,

3rd SERIES

HEADQUARTERS CAVALRY CORPS,
June 17, 1863

I. This corps will encamp at Aldie to-night. To-morrow the First Division will march by the way of Circleville post-office and Hamilton to Waterford, and from thence to Noland's Ferry.

II. The Second Division to-morrow will march by Philomont Purcellville, and Waterford, and thence to Noland's Ferry.

III. The regiment of the Second Division at Middleburg to-night will pass without its wagons to Union; thence to Snickersville; thence to Purcellville and Wheatland, and thence to Waterford and Noland's Ferry.

IV. Each column will have a regiment and a section of artillery as advance guard, and one brigade, with a section of artillery, will form the rear guard; the trains, stragglers, led-horses, &c., will precede this brigade.

V. Headquarters will be at Aldie to-night. Division commanders, on arriving in camp, will send staff officers for orders.

By order of Brigadier-General Pleasonton:

A. J. ALEXANDER,

Chief of Staff, and Assistant Adjutant-General.

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JUNE 17, 1863-midnight.

Commanding Officer Twelfth Corps:

The major-general commanding directs that, on receipt of this order, if after 3. 30 a. m. or at that hour, you move your corps to Leesburg. Hold it, and open communication with the fords on the Potomac in that vicinity, and hold them. Captain McKee, with a detachment of cavalry of this army, ought to be at the mouth of the Monocacy to- night; bridge trains and two regiments of infantry to-morrow noon. General Pleasonton encountered Fitz. Lee's brigade of cavalry at Aldie at 4 o'clock this afternoon. Stuart wa reported at Middleburg. The inclosed dispatch* would lead to a presumption that they are there to cover White's crossing the river, or else to join him. This must be prevented. General Pleasonton may be sending in a force toward Leesburg, as he has been directed to do so. Guard against collision with him. Inform his officers there, should you

meet them, of all you can learn regarding enemy's movements.

DANL. BUTTERFIELD,

Major-General, Chief of Staff.

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*See Tyler to Schenck, 11 a. m., preceding.

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