He was counting the minutes now before he would be relieved, when suddenly, as he was passing the entrance that opened on the corridor, he heard a sound that startled him.
He stood stock still, every trace of sleepiness gone in an instant and all his faculties keenly on the alert. But nothing happened and he relaxed.
"Pshaw!" he said to himself impatiently. "What's the matter with me? Am I letting what Tom said about ghosts get on my nerves?"
Then the sound came again, and this time Bart knew that he was not mistaken.
CHAPTER V
CONSPIRATORS
What Bart heard was the sound of human voices.
At first the thought flashed across him that they might be those of some of his comrades, sent back by Lieutenant Winter to look for the missing men.
But he dismissed this thought almost as soon as it was formed. There was a peculiar quality about the tones that was not American, a coarse guttural sound such as he had grown only too familiar with in the streets of Coblenz. Those who were talking were Germans.
He listened intently.