 Complete the following phrase:  The offensive began with a westward move on January 20, 1863, in unseasonably mild weather. Burnside, with a head start, altered his plan to aim at Banks Ford, a closer, quicker crossing. At dawn of January 21, engineers would push five bridges across; after that, two grand divisions would be over the river in four hours. Meanwhile, another grand division would distract the Confederate troops by repeating the 