"He's a German, anyhow," persisted Trefusis.
The man still hesitated. Then he hailed a seaman.
"Where is the post office?" he asked. "I wish to telegraph. Is there time before the boat sails?"
Receiving an affirmative reply the man hurried off.
"Come on!" exclaimed Ross.
Neither of the lads had now any doubts as to the man's identity. The beard and moustache were false, but the voice was the same—von Ruhle's.
Keeping close to the wall of the line of sheds, the lads followed the spy at a distance of about fifty feet. More than once von Ruhle glanced furtively over his shoulder, as if suspecting that he was being tracked.
Presently a man, reeling along the quay, approached. The spy made no effort to avoid him. As the inebriated one rolled past he whispered a few words. The effect was instantaneous. Instead of continuing his way towards the post office, von Ruhle turned and made off abruptly in the direction of the gate of the Company's premises.
"An accomplice," whispered Vernon. "He's been warned."
They had to wait until the man who had feigned drunkenness had disappeared. By this time the German had gained a considerable distance. To get the assistance of the detective was out of the question.