uniform loupe July 18, 1861
The result of the first skirmish will determine the second game: an early attack or the historical one.

uniform loupe July 18, 1861
The first US division has reached Centreville. McDowell has ordered to scout the confederate defenses along the Bull run and to draw enemy's attention to the center.
Never mind ?
The whole army of the Potomac is on the other bank. But the rebel line is stretched and the arrival of the second division will improve the balance of forces.

uniform loupe July 18, 1861, 12:00 PM
Tyler has exceeded his orders. The first US division is crossing the Bull run upstream of the Stone bridge.
Hidden in the wood, Terry's squadron skirmishers engage the Richardson brigade. But they finally give ground under the fire of the light battalion's rifles.

uniform loupe July 18, 1861, 2:40 PM
The 4th South Carolina regiment and 1st Louisiana battalion have been shelled for almost three hours by Tyler's thirteen guns.
The New York and Wisconsin regiments of the Sherman brigade are leading the assault against the Stone bridge entrenchments.

uniform loupe July 18, 1861, 3:20 PM
Meanwhile, Hunter's second US division is deploying in front of Mitchell's ford.
The artillery duel is rumbling.

uniform loupe July 18, 1861, 4:00 PM
The Bonham brigade and the Washington artillery battalion have rushed to the rescue of Cocke's Virginians.
Exposed, the Schenck brigade is routed between Ball's ford and the Stone bridge, but the counterattack is already hopeless.

uniform loupe July 18, 1861, 4:00 PM
The Stone bridge and the heights above Mitchell's ford are secured, but the horsemen of the 30th Virginia regiment are infiltrating along the Cub run.
In the event of a confederate attack from Union mill, Hunter brings back the Burnside brigade to Centreville.

uniform loupe July 20, 1861
After a successful skirmish on July 18, McDowell could have been more aggressive.
Tyler's daring has boosted the morale of the whole federal army. McDowell has waited for supplies before launching the decisive attack. Johnson's confederate reinforcements from the Shenandoah are not all in line.

uniform loupe July 21, 1861
The rebels defense line is strong. Tyler's recklessness has boosted their morale. Now cautious, McDowell has filled two days to plan a flank attack. Meanwhile by railroad, Johnson's army of the Shenandoah has reinforced Beauregard's army of the Potomac.
The artillery of the first US division is pounding the defenses of the Stone bridge. Meanwhile, two other divisions are outflanking the confederate line, north of Henry hill.

uniform loupe July 18, 1861
This scenario lasts 124 turns, until the evening of the 21st. Many reinforcements are expected for both sides

uniform loupe July 18, 1861, 12:00 PM
Tyler's first US division is entrenching on the heights above Blackburn's ford.
At a range of 3000 yards, the five Parrott rifles wreak havoc on Beauregard's headquarters and Washington artillery battalion.

uniform loupe July 18, 1861, 4:00 PM
Hunter's second US division is attacking along the Warrenton turnpike.
Palmer's regular cavalry battalion surprises Terry's squadron upstream of the Stone bridge.

uniform loupe July 19, 1861, 2:00 PM
Heintzelman's third US division has crossed the creek then occupied Matthews hill. Against such a firepower, Evans' one thousand men can't hold the Warrenton/Sudley crossroads.
The confederate lines of communication are seriously threatened.

uniform loupe July 20, 1861, 7:20 AM
While Johnston's reinforcements from the Shenandoah are concentrating in the vicinity, the 1st Virginia cavalry charges the artillery of the 3rd US division on Matthews hill. Two rifles and two smoothbores will be captured.

uniform loupe July 21, 1861, 3:20 PM
Despite frequent showers, the fighting for the Warrenton/Sudley crossroads is intense.

uniform loupe July 21, 1861, 10:00 PM
The 2nd US division still holds the Stone bridge but the rebels have regained the crossroads.