Maryland Heights, MD. June 19, 1863.

Major-General HOOKER:

General Scammon has his headquarters at Charleston, W. Va. If Harper's Ferry is to be attacked, it will probably be to-morrow morning. We have done all we can to be ready.

DAN. TYLER,

Brigadier-General.

Headquarters Army of the Potomac,

June 19, 1863-3. 45 p. m.

Brigadier-General TYLER, Sandy Hook:

It is impossible to get any clear and connected idea of the position of the enemy or any of his troops on your side of the river. The newspapers say much more than we have ever learned from any other source. Can you make a concise statement of the position as it exists; your troops, their character, number, and position; whose department they are in; and the position of the enemy, his actual advances into Maryland or Pennsylvania, and the force?

DANL. BUTTERFIELD,

Major-General.

June 19, 1863-8 p. m.

General TYLER, Harper's Ferry.

General Hooker desires to know how long you can hold your position, if attacked by 30, 000 men; also if you are satisfied in your own mind that Ewell's corps has crossed the Potomac and are now in Maryland.

DANL. BUTTERFIELD,

Major-General, Chief of Staff.

MARYLAND HEIGHTS, MD., June 19, 1863.

(Copy received, War Department 6. 10 p. m.)

Major-General BUTTERFIELD:

I have reported everything ascertained as to the rebel troops and their position. Everywhere within my reach, I reported what I considered ascertained facts as to rebel position at and near Sharpsburg. This morning my position and amount of troops you can obtain from Baltimore, and I do not wish to enter into details, for fear of accident, as I am not sure the rebels have not our cipher, as all the dispatches coming on to me are confused. I expect to hold this position very considerably longer than it was held last year.

DAN. TYLER,

Brigadier-General.

Baltimore, June 19, 1863-5. 50 p. m.

Brigadier General DANIEL TYLER, Harper's Ferry:

General Schenck has kindly furnished us with a copy of your dispatch to him of this morning, about clearing the wreck of our train burned by the enemy at Point of Rocks.