ford. He ordered two howitzers under Captain (Capt.) Romeyn B. Ayres to bombard the Confederates he could see—guns of the Alexandria Artillery and the Washington Artillery—but the fire had no visible effect. As a result, Tyler ordered Colonel (Col.) Israel B. Richardson and part of his brigade forward. Richardson sent out a portion of the 1st Massachusetts Infantry towards the Confederate line. The Massachusetts regiment wore gray uniforms instead of the standard Union blue, which caused initial confusion, as the Confederates were also clad in gray. After the 1st Massachusetts, Richardson deployed the 1st Michigan Infantry, 2nd Michigan Infantry, 3rd Michigan Infantry, and 12th New York Infantry regiments. The Union advance met initial resistance from the 1st Virginia Infantry, 11th Virginia Infantry, and 17th Virginia Infantry regiments of Longstreet's brigade. Tyler ordered Ayres to move his guns closer to the action, accompanied by cavalry, and he sent the rest of Richardson's brigade toward the ford. The 12th New York Infantry began to retreat under heavy fire, exposing the rest of Richardson's line, particularly the 1st Massachusetts, to Confederate fire. Ayres, his battery having used up much of its ammunition, withdrew his two howitzers from the field. During the exchange, Union cannons fired an estimated 415 shots, and the Confederate cannons fired an estimated 310. Tyler realized that the Confederates had a strong force at the ford, and ordered the rest of his infantry to withdraw. After Richardson's brigade had completed its withdrawal, a second of Tyler's brigades commanded by William T. Sherman arrived on the field, although Sherman's brigade was only subjected to light shelling. Col. Jubal A. Early arrived with his Confederate brigade after marching two miles north from Beauregard's headquarters at Wilmer McLean's house. The availability of this additional firepower completed the Confederate victory, and a reinforced Washington Artillery kept the Union troops under fire as they retreated. Col. Patrick T. Moore of the 1st Virginia Infantry, later a Confederate brigadier general, received a severe head wound in the skirmish and was incapacitated for further field service. Tyler's Union division suffered 83 casualties in the action, while the Confederates lost 68 men. Aftermath The failed reconnaissance-in-force at Blackburn's Ford led McDowell to decide against a frontal assault along Bull Run Creek. He decided to attempt to cross the stream beyond the Confederate left flank, the maneuver he employed at the First Battle of Bull Run on July 21.