P. S.-I am without ammunition for rifled cannon (4-pounder rifled to parrott), also without friction primers. I am without a regular quartermaster, and consequently have my movements greatly embarrassed. If I a m to continue with this command i wound be glad to have the privilege to recommend for appointment, so that I can organize according to what I believe most efficient condition.

OCTOBER 18, 1861.-Reconnaissance towards Occaquan River, Virginia.

Report of Brigadier General Israel B. Richardson, U. S. Army.

HEADQUARTERS RICHARDSON'S BRIGADE,
October 19, 1861.

SIR: In obedience to your instructions, I left this camp yesterday at 3.30 p. m. to make a reconnaissance in the direction of occoquan, my force consisting of two regiment of infantry, of half battery of artillery, and one company of cavalry. The command proceeded as far as Accotink Creek, taking the Telegraph road. On reaching this stream I came to a halt, and sent half a company of cavalry to Pohick Church, the other half to the Accotink Village, and posted a company of infantry to our right on the road leading up the creek. This company on morning up the road fell in with enemy's pickets, who immediately ran into their camp across the creek and gave the alarm. The long roll beat some 20 minutes from three different camps on our right, showing that they were there in some force. After resting the command half an hour I sent to order in both detachments of cavalry, who soon came in, finding no enemy at the village or at the church. The enemy occupy the valley on the right of the road leading from the crossing to the church. from what I could learn, the road from Pohick Church to Occoquan is clear, and but few troops are at the latter place. Having finished the object of the expedition, I moved the command back to camp, where it arrived at 12 o'clock, having marched some 20 miles. I took this opportunity of moving forward our pickets, who occupy a direct line from Windsor Hill to the mouth of Dogue Creek.

I have the honor to be, very respectfully, your obedient servant,

I. B. RICHARDSON,

Brigadier-General.

Brigadier General S. P. HEINTSELMAN, U. S. Army.

[Indorsement.]

HEADQUARTERS DIVISION, FRONT LYON,
October 19, 1861.

This reconnaissance shows that the rebels are in force between Long Branch and Accotink Run, above the Telegraph road. If there are any south of this rod it is not probable that they are in force. Our pickets now extend from the mouth of Dogue Run to Windsor's Hill,m which is a commanding position and overlooks the valley. Accotink Village was abandoned, as well as Pohick Church, several days ago.

Respectfully forwarded.

S. P. HEINTZELMAN,

Brigadier-General Volunteers, Commanding.

The rebels are believed to belong to General Ewell's brigade.