y General Barnard say that "it was one
of the most formidable obstacles that could be opposed to the advance of
an army,--an obstacle to which an ordinary _river_, though it be of
considerable magnitude, is comparatively slight."

The labors of the engineers in bridging this formidable swamp are
detailed with considerable minuteness. Ten bridges, of different
characters, were constructed, though some of them were never used,
because the enemy held the approaches on his side of the river.

We are glad that General Barnard has elaborated this part of his Report.
There is a melancholy interest attaching to the Chickahominy. To it, and
to the events connected with it, history will refer the defeat of
General McClellan's magnificent army, and the failure of the Peninsular
campaign. And what a lesson is here to be learned! The fate of the
contending armies was suspended in a balance. The hour when a particular
bridge was to be completed, or rendered impassable by the rising floods,
was to turn the scales!

That mistakes were committed on the Chickahominy the country is prepared
to believe. Our army was placed astride of that stream, and in this
situation we fought two battles, each time with only a part of our
force; thus violating, not only the maxims of war, but the plainest
principles of common sense.

The Battle of Fair Oaks began on the thirty-first of May. At that time
our army was divided by the Chickahominy. Of the five corps constituting
the Army of the Potomac, two were on its right bank, or on the side
nearest to Richmond, while the other three were on the left bank. There
had been heavy rains, the river was rising, and the swamps and
bottom-lands were fast becoming impassable. None of the upper bridges
had yet been built. We had then only Bottom's Bridge, the
railroad-bridge, and the two bridges built by General Sumner some miles
higher up the river. Bottom's Bridge and the railroad-bridge were too
distant to be of any service in an emergency such as a battle demands.
At the time of the enemy's attack, which was sudden and unexpected,
completely overwhelming General Casey's division, our sole reliance to
reinforce the left wing was by Sumner's corps, and over his two bridges.
It happened to be the fortune of the writer to see "Sumner's upper
bridge,"--the only one then passable,--at the moment the head of General
Sumner's column reached it. The possibility of crossing was doubted by
all present, including Gene