two 6-pounders.

At Union Mills Ford, Brigadier-General R. S. Ewell's Second Brigade, of
three Infantry regiments, three Cavalry companies, and four 12-powder
howitzers--Colonel Jubal A. Early's Sixth Brigade, of three Infantry
regiments and three rifled pieces of Walton's Battery, being posted in
the rear of, and as a support to, Ewell's Brigade.

[Johnston also found, on the 20th, the Reserve Brigade of Brig.
Gen. T. H. Holmes--comprising two regiments of Infantry, Walker's
Battery of Artillery, and Scott's Cavalry-with Early's Brigade, "in
reserve, in rear of the right."]

The disposition and strength of Beauregard's forces at these various
points along his line of defense on Bull Run stream, plainly shows his
expectation of an attack on his right; but he is evidently suspicious
that it may come upon his centre; for, as far back as July 8th, he had
issued special orders to the effect that:

"Should the Enemy march to the attack of Mitchell's Ford, via
Centreville, the following movements will be made with celerity:

"I. The Fourth Brigade will march from Blackburn's Ford to attack him on
the flank and centre.

"II. The Third Brigade will be thrown to the attack of his centre and
rear toward Centreville.

"III. The Second and Sixth Brigades united will also push forward and
attack him in the rear by way of Centreville, protecting their own right
flanks and rear from the direction of Fairfax Station and Court House.

"IV. In the event of the defeat of the Enemy, the troops at Mitchell's
Ford and Stone Bridge, especially the Cavalry and Artillery, will join
in the pursuit, which will be conducted with vigor but unceasing
prudence, and continued until he shall have been driven beyond the
Potomac."

And it is not without interest to note Beauregard's subsequent
indorsement on the back of these Special Orders, that: "The plan of
attack prescribed within would have been executed, with modifications
affecting First and Fifth Brigades, to meet the attack upon Blackburn's
Ford, but for the expected coming of General Johnston's command, which
was known to be en route to join me on [Thursday] the 18th of July."

The knowledge thus possessed on Thursday, the 18th, by Beauregard, that
Johnston's Army is on its way to join him, is of infinite advantage to
the former. On the other hand, the complete ignorance, at this time, of
McDowell on this point,--and the further fact that he has been lulled
i