He sent scouts ahead and threw out flankers.

When they reached the forest the ranks opened out, and, without losing touch, a thousand men rode among the trees as easily as they had ridden in the open fields.
They reached the crest of the last slope and Stuart, sitting his horse with Harry and St.Clair on either side, looked through his glasses at the valley below.
"Our people still hold it," he said.

"I can see their gray uniforms and I have no doubt the besiegers are still in the forest.

Yes, there's their signal!" The heavy report of a cannon shot rolled up the valley and Harry saw a shell burst over the fort.

Carrington was still at work, playing upon the nerves of the defenders.
"While we have ridden through the forest," said Stuart, "a cavalry charge here is not possible.