military department . Transportation is provided for your regiment via the Philadelphia, Wilmongton, and Baltimore Railroad .

By command of Major-General Halleck, general-in-Chief:

C. F. RUFF,

Lieutenant-Colonel Third Cavalry, U. S. Army, Comdg, Philadelphia. Although I had your order to proceed to Harrisburg, I could not doubt, you would desire me to where there was the most need of my services, and at once marched regiment forward, sending you the following notification of this change:

PHILADELPHIA, June 17, 1863-Midnight .

J. T. SPRAGUE,

Adjutant-General:

I have received orders from Major-General Halleck to proceed to Baltimore, and the regiments is now on the cars ready to proceed to that city . I presume this will receive the sanction of the Governor .

M. LEFFERTS, Colonel,

Commanding Seventh Regiment .

Upon arrival at Baltimore, I reported to Major-General Schenck, and was ordered on duty in the city for that night and following day, when we were directed to relieve the One hundred and twenty-ninth Regiment New York State Volunteers, Colonel Porter, at Fort Federal Hill . We remained at this fort until the 5th of July, during which time were actively engaged on outpost and other duty, being frequently reduced to 150 men in the fort . On the 5th of July, we were ordered to report to general Briggs, and proceed to Frederick, Md., in light marching order, leaving tents, knapsacks, and baggage behind . This order was received during the night, and although two or four outpost were distant 9 and 12 miles, respectively, they were called in, and the regiment moved from the fort at 8 a. m., in a drenching rain . At Monocay Junction, we were detained some time awaiting the decision of, I believe, Major-General Meade, whether the troops then on the road should go to Harper's Ferry . Finally, we received orders to march to Frederick City (by order), leaving two detachments for duty near that city . The regiment went into camp on the road to Harper's Ferry . We were here assigned to the Third Army Corps, Army of the Potomac . On the 8th of July, by the following, order I assumed command of Frederick, relieving General French, who was ordered to the command of the Third Army Corps:

SPECIAL ORDERS, No. 24.

HEADQUARTERS, Frederick City, July 8, 1863.

* * * * * * *

II. Colonel Lefferts, Seventh New York Regiment, is detailed on special duty in Frederick City . Colonel Lefferts will make such arrangements for guarding the depots, and for the police required for the city, as he may deem necessary . III. Major H. A. Coole, Maryland cavalry, will report to Colonel Lefferts for instruction . IV. The battalion. Fourteenth [First] Massachusetts Heavy Artillery, under Major Rolfe, now on duty at Monocacy Junction, will be relieved by a detachment from the Seventh New York Regiment, after which Major Rolfe will report to these headquarters in person . By order:

FRENCH,
Major-General .

As Monocacy Junction was made grand depot for the Army of the Potomac, and a large portion of the army then moving through