Tyler reached the Stone Bridge before six in the morning and opened fire on a Confederate force under Colonel Evans on the other side of the run. For some time this was kept up, and Evans was much puzzled that the Federals did not attempt to cross the bridge; they merely kept up a desultory fire. The failure of the Union troops to advance led Evans to believe that Tyler's attack was only a feint and that the real attacking force would approach from some other direction. This belief was confirmed when he descried a lengthening line of dust above the tree-tops far in the distance, north of the Warrenton turnpike. Evans was now convinced (and he was right) that the main Union army was marching to Sudley's Ford, three miles above the Stone Bridge, and would reach the field from that direction. Quickly then he turned about with six companies of brave South Carolinians and a battalion of "Louisiana Tigers" and posted them on a plateau overlooking the valley of Young's Branch, a small tributary of Bull Run. Here, not far from the Matthews and Carter houses, he awaited the coming of the Federals. His force was stationed overlooking the Sudley and Newmarket road and an open field through which the Federal troops would be forced to pass to reach the higher ground held by the Confederates. Two 6-pound howitzers were placed to sweep the field of approach, one at each end of Evans' line of defense. With guns loaded, and howitzers ready to pour their charges into an advancing force, the Southerners stood and watched the line of dust that arose above the trees. It moved slowly to the westward. Then, where the Sudley road turns to the southward to cross the Sudley Ford, it followed the trend of the highway. It reached the crossing of Bull Run, and the line of dust faded as the Federals spread into battle-line behind the expanse of woodland that hid each column from the other's view. It was nearing ten o'clock. The rays of the summer sun were beating in sweltering heat upon the waiting troops. Those who could find shelter beneath the trees moved from their places into the shade. Heavy banks of storm clouds were gathering on the horizon, giving promise of relief from oppressive warmth. A silence settled over the ranks of the Confederates as they watched the edge of the woodland for the first appearance of the approaching troops.