...y of the Potomac. Not satisfied with the tardy movements of McClellan, Lincoln supplanted him in command, at Warrenton, with Burnside, who at once hastened to execute an on to Richmond, by way of Fredericksburg , thinking that by taking advantage of a shorter line of movement he could reach his objective without being intercepted by Lee; but when, on the 15th, he pressed his advance toward Fredericksburg, th...