CAMP NEAR POOLESVILLE, July 2, 1861.

COLONEL: The six companies of the Ninth New York advanced yesterday afternoon to Point of Rocks; First Pennsylvania Artillery (Colonel Patterson) started for Licksville, but the heavy rain which came on rendered the roads impassable, and he was obliged to halt this side the Monocacy. The battalion Twenty-fifth Pennsylvania Regiment arrived last night. The provision train with much difficulty reached here from Seneca this morning.

Captain Magruder has started on his march to Washington with Company H, Second Cavalry. The President's Mounted Guard is at Edwards Ferry, and will march for Washington via Seneca, to-morrow morning, with the Third Battalion District of Columbia Volunteers. Piper's section of artillery will await the assembling of the District of Columbia Volunteer battalions at Seneca, and then proceed to Washington, accompanied by the President's Mounted Guard.

The movement of the First New Hampshire Regiment from this place will necessarily depend on the progress of the trains. I hope to see Harper's Ferry to-night.

Very respectfully, colonel, your most obedient servant,

CHAS. P. STONE,

Colonel Fourteenth Infantry, Commanding.

Lieutenant Colonel E. D. TOWNSEND, Assistant Adjutant-General.

POINT OF ROCKS, July 3, 1861.

I have just returned from Sandy Hook, opposite Harper's Ferry, to which point a division of the New York Ninth and the First Pennsylvania Artillery have been advanced. A messenger came in to me there from Sharpsburg, bringing intelligence that there was an affair at Falling Waters yesterday, in which the Government troops captured five hundred prisoners and six pieces of artillery. Our loss three killed and some wounded.

The messenger states that there is a battle going on to-day on the road between Falling Waters and Winchester. Harper's Ferry appears to be deserted. I could see but half a dozen people in the town without my glass. Shall I have any further instructions?

CHAS. P. STONE.

Colonel, Commanding.

Lieutenant Colonel E. D. TOWNSEND

POINT OF ROCKS, July 4, 1861.

COLONEL: I reported night before last and yesterday by telegraph. I visited the river opposite Harper's Ferry yesterday and to-day. There are now at that point the Pennsylvania First Regiment, part of the New York Ninth, and Colonel Cake's command. The train of provisions and ammunition has been detained on the road, but will be up to-night.

I have no news from General Patterson since my telegram of last night. Had I only a little artillery and cavalry a good advance could be made, co-operating with General Patterson. I hope to occupy the town of Harper's Ferry to-night or to-morrow morning, in spite of the want of artillery.

The people received the troops at Berlin, Knoxville, and Sandy Hook