that eyes watched them from groves and fence corners, keeping cautiously
out of the way, because it was sometimes difficult now to tell Federals
from Confederates. But it did not matter to Sherburne. He kept a
straight course for the Potomac, at least half of his men knowing
thoroughly every foot of the way.

"What time can we reach the river and the place at which they say
McClellan is going to cross?" asked Harry.

"By midnight anyway," replied Sherburne. "Of course, we'll have to slow
down as we draw near, or we may run square into an ambush. Do you see
that grove about two miles ahead? We'll go into that first, rest our
horses, and take some food."

It was a fine oak grove, covering about an acre, with no undergrowth and
a fair amount of grass, still green under the shade, on which the horses
could graze. The trunks of the trees also were close enough together to
hide them from anyone else who was not very near. Here the men ate cold
food from their haversacks and let their horses nibble the grass for a
half hour.

They emerged refreshed and resumed their course toward the Potomac.
In the very height of the afternoon blaze they saw a horseman on the
crest of a hill, watching them intently through glasses. Sherburne
instantly raised his own glasses to his eyes.

"A Yankee scout," he said. "He sees us and knows us for what we are,
but he doesn't know what we're about."

"But he's trying to guess," said Harry, who was also using glasses.