men it had filled his with joy, as he thought of the
innumerable brooks and creeks that were pouring their swollen waters into
the Potomac, already swollen too. He meant now to follow Sherburne's
force, see what plan it would attempt, what point, perhaps, it would
select for the bridge, and then bring the Union brigades in haste to
defeat it.

It is said that men often feel when they are watched, although the
watcher is invisible, but it was not so in Sherburne's case. He did not
in the least suspect the presence of Shepard or of any foe, and the spy,
after he had seen all he wished, withdrew, with the same stealth that had
marked his coming.

An hour after midnight all were awakened and they rode away. The next
day they reached the Potomac near Williamsport, where their pontoon
bridge had been destroyed, and looked upon the wide stream of the Potomac,
far too deep for fording.

"If General Lee is attacked on the banks of this river by greatly
superior forces," said Sherburne, "he'll have no time to build bridges.
If we didn't happen to be victorious our forces would have to scatter
into the mountains, where they could be hunted down, man by man."

"But such a thing as that is unthinkable, sir," said Harry. "We may not
win always, but here in the East we never lose. Remember Antietam and
the river at our back."

"Right you are, Harry," said Sherburne more cheerfully. "The general
will get us out of this, and here is where we must cross. The river may
run down enough in two or three days to permit of fording. God grant
that it will!"

"And so say I!" repeated Harry with emphasis.

"I mean to hold this place for our army," continued Sherburne.

"A reserved seat, so to speak."

"Yes, that's it. We must keep the country cleared until our main
force comes up. It shouldn't be difficult. I haven't heard of any
considerable body of Union troops between us and the river."

They made camp rapidly in a strong position, built their fires for
cooking, set their horses to grazing and awaited what would come.
It was a dry, clear night, and Harry, who had no duties, save to ride
with a message at the vital moment, looked at once for his friends,
the Invincibles.

St. Clair met him and held up a warning hand, while Happy touched his lip
with his finger. Before the double injunction of silence and caution,
Harry whispered:

"What's happened?"

"A tragedy," replied St. Clair.

"And a victory, too," said Hap