A Frenchman came to-day from Culpeper, who left Richmond nine days since. There was nothing on the road when he came through but 80 cavalry of the Scott Rangers at Gordonsville. They were talking at Gordonsville, of the return of Jackson, whom he left beyond Richmond. The Frenchman, who has been a resident of Richmond, says they have but six divisions, and that their force amounted to 90,000 at the outside. I sent him to your headquarters. He may arrive to-morrow night.

IRVIN McDOWELL,

Major-General.

HEADQUARTERS ARMY OF VIRGINIA, Washington, July 21, 1862.

Major-General McDOWELL,
Commanding Third Corps d'Armee, Warrenton, Va.:

Move your entire division at Warrenton, with the exception of one regiment, to the crossing of Hedgeman's River, on the road to Sperryville, but do not cross the river till you receive orders to do so from these headquarters. The one regiment above specified will be left at Warrenton.

By command of Major-General Pope:

GEO. D. RUGGLES,

Colonel and Chief of Staff.

HEADQUARTERS ARMY OF VIRGINIA, Washington, July 21, 1862.

Major-General BANKS:

I send you copy of dispatch just received from General King:*

FALMOUTH, VA., July 20, 1862-12 midnight.

Major-General POPE:

The cavalry which left here at 7 o'clock last evening have just returned. They fully accomplished the object of the expedition. Arriving at Beaver Dam early this morning, they broke up the Central Railroad for several miles, burnt the depot at Beaver Dam, cut the telegraph communication, and created a general alarm in the at part of the State. In the depot destroyed were 100 barrels of flour and 40,000 cartridges, besides other goods. The cavalry must have made a march of 80 miles in the thirty hours. They bring back one prisoner, a captain in the Confederate service. They report that about four brigades have passed up the Central Railroad during the last few days, and that the enemy are expecting us to attack them at Gordonsville or Louisa Court-House. Only one private was wounded during the march. I will send full particulars by mail in the morning.

RUFUS KING,
Brigadier-General, Commanding.

You perceive from this dispatch what cavalry can do when led boldly, vigorously, and rapidly. The mistake of General Hatch was in taking infantry and wagon trains, by which he lost and opportunity to distinguish himself greatly and to render immense service to the country. He has still the chance, and I trust for his own sake he will not lose it. Direct him to take four regiments of cavalry, with two days' cooker rations, and nothing else, and make a forced march upon Charlottesville to destroy the railroad between that place and Gordonsville and be-

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*Copy of King's dispatch also sent to McDowell.

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