ANNAPOLIS, April 24, 1861.

To his Excellency ANDREW [G.] CURTIN,

Commander-in-Chief of the Forces of Pennsylvania:

SIR: Should this dispatch be forwarded to you, countersigned by his excellency Thomas H. Hicks, governor of Maryland, you will please to understand that the insurgents have surrendered Pikesville Arsenal, and that it therefore will not be necessary to advance your troops, as you were yesterday requested by me.

B. F. BUTLER,

Brigadier-General.

PHILADELPHIA, April 24, 1861.

Colonel LORENZO THOMAS, Adjutant-General U. S. Army:

COLONEL: The orders of the Lieutenant-General Commanding to secure the forts on the Delaware have been anticipated. Captain Gibson reported last week that he was able to hold Fort Delaware, but requested that the remainder of his company be directed to join him. I have detailed one hundred men (raw volunteers) to be placed under his command.

Fort Miffin is held by a detachment of volunteers. I inclose herewith a memorandum from a source believed to be reliable. I also inclose copy of a letter to Captain Rodgers, of the Navy. Major Thomas, Second Cavalry, has telegraphed the orders received from headquarters. Orders have been given to purchase horses, and I have directed the ordnance officers at Allegheny and Frankford to report as to the ammunition and equipments.

I have respectfully to request that a commissary be sent here without delay, furnished with funds to purchase rations and supply the troops when mustered into service. Three regiments from this State have been sent forward, and the residue of the quota only awaits organization.

Major F. J. Porter, who has carefully examined the ground, concurs with me in the opinion that it is impracticable at present to throw re-enforcements into Washington by the interior of Pennsylvania, and all my efforts shall be directed to the route via Annapolis.

I have directed Colonel Thomas to be ready to organize a wagon train.

Very respectfully, your obedient servant,

R. PATTERSON,

Major-General.

[Inclosure.]

HDQRS. MILITARY DEP'T OF PENNSYLVANIA, Philadelphia, April 24, 1861.

Captain RODGERS, Frigate Constitution:

CAPTAIN: Major-General Patterson learns through S. M. Felton, esq., that you informed him that there is a small fort situate at the entrance of Annapolis Harbor, which it is highly desirable should be taken possession of, armed, and occupied. If you can supply ten guns for the purpose, or a sufficient number to hold it, you are hereby authorized to make a requisition upon the colonel of any regiment on the route to Washington for a detachment of a hundred men to garrison it.

As the troops on the route have little knowledge of guns, you will please detail one or more instructors.

Very respectfully, your obedient servant,
CRAIG BIDDLE, A. D. C.