... cross the Rappahannock at Fredericksburgh, and to move at once upon Richmond. Delays, resulting from various causes, without fault of the General, permitted the insurgents to occupy the heights of Fredericksburgh , and when, at length, in December, General Burnside crossed the Rappahannock, his assault upon Lee's well-fortified position failed. He skilfully recrossed the river without loss. General Hooker ...