Meanwhile, General Warren on Little Round Top saw the importance of the hill as a tactical position on Meade’s left. The signal officers were preparing to leave; he ordered them to remain and to keep waving their flags so as to lead the Confederates to believe that the hill was occupied. He dispatched a messenger to Devil’s Den, where a Union battery was posted, with an order that a shot be fired to produce confusion in the woods in front, through which Hood’s forces were supposed to be advancing. Seeing the reflection of the sunlight from Confederate muskets, he realized that if this important position were to be held, it would be necessary to get troops there without delay. Quickly he sent a member of his staff to Sickles for troops. Sickles said none could be spared. Warren sent another staff officer to Meade, who immediately ordered Sykes to move his Corps to Little Round Top. Barnes’ Division of this Corps had already been called for by Sickles to defend his line, and three brigades, Vincent’s, Tilton’s, and Sweitzer’s, were moving toward the Wheatfield. Learning of the need of troops on Little Round Top, Vincent moved back, skirted the east side of Little Round Top, and went into position between Little and Big Round Top, arriving just before the Confederates from Hood’s right advanced over Big Round Top. Having watched these movements, Warren rode down to the crossing of what is now Sykes Avenue and the Wheatfield Road. There he met Colonel O’Rorke, in command of the 140th New York, and ordered his regiment, together with Hazlett’s battery, to the crest of the hill. With the addition of Weed’s Brigade, the combined forces held the Round Tops. There was a desperate engagement in which both contestants displayed courage of a very high order. The Union soldiers were victorious, and Meade’s left was secured against further attack. The Peach Orchard and the Wheatfield. After the struggle for the possession of Little Round Top, the other Confederate brigades of Hood and McLaws advanced rapidly. A lack of coordination in their movement allowed Meade to bring up supports. Three brigades of Anderson’s Division of Hill’s Corps advanced against Humphreys’ line, in the following order: Wilcox, Perry, Wright. Wounded, General Pender was unable to direct Posey and Mahone in support of Wright, and Wright was obliged to withdraw. Humphreys was compelled to change front in order to meet the assault on his flanks. This maneuver served to stay the Confederate attack for a brief time. The Valley of Death between the Round Tops and the opposite height was now a seething mass of opposing forces, enshrouded in clouds of smoke.