What did the woman know which enabled her to wield such influence over McDonald?
What was the trap they proposed springing?
The Sergeant felt that he could solve these problems if given an opportunity, but he was handicapped by his position; he could not leave his troop, could not meet or mingle with the suspected parties; was tied, hand and foot, by army discipline.

He could not even absent himself from the post without gaining special permission.

He swore to himself over the hopelessness of the situation, as he tramped through the blackness toward the guard-house.
The sentinel glanced at his pass, scrutinizing it by the light of a fire, and thrust the paper into his pocket.

Hamlin advanced, and at the corner saluted the officer of the day, who had just stepped out of the guard-house door.
"Good evening, Sergeant," the latter said genially.

"Just in from town?
I expect they are having some dance down there to-night." "Yes, sir," hesitatingly, and then venturing the inquiry.