Enough rain has fallen to permit Union engineers to construct a pontoon bridge of seventy-five boats across the swollen Potomac River near Berlin, Virginia.

For the past several days, the Army of the Potomac has been marching across this bridge from Maryland into Virginia, where General Lee’s forces retreated after their September defeat at Antietam.

General Burnside’s corps is leading the advance into Virginia while General McClellan’s camp has been established in Berlin, near the river.

[Ed: Lincoln will complain that it took McClellan eight days to cross the Potomac while it took Lee only one. Lincoln will remove McClellan from command in six days.]

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