 The 21st crossed the Rappahannock on December 12 via the pontoon bridges that had been constructed by the Union army and spent the night along the west bank of the river . On the morning of the 13th , the regiment was ordered to the west part of the city , near the base of the heights . Here they removed the grey overcoats that had been issued to them for fear of being mistaken for Confederates . From this position , the 21st watched an assault by a portion of the II Corps over the open plain leading to heights and were shocked by the carnage that resulted from the failed attack . Just after this assault , Ferrero 's brigade was ordered to attack the heights and the 21st formed a line of battle on the open ground slightly after noon . The 21st advanced , according to Walcott , " under the best directed artillery fire we had ever suffered or seen . " Color bearers were repeatedly shot down . One , Sgt. Thomas Plunkett , was hit by an artillery shell that took off his right arm and left hand . Despite his wounds , he managed to keep the colors from falling . The flag is today in the collection at the Massachusetts State House and still bears the stains from Plunkett 's wounds . Plunkett was awarded the Medal of Honor for his bravery at Fredericksburg . 
