“I do believe it is,” said Miss Chain, as the man hurried onwards. “Surely he is Filcher who robbed us in Boulogne, anyway he is the ‘spy’—the one who has been tormenting us here.”

During the time that Trigger and Warner were absent at the police station, the amateur aeronaut had a few hasty words with Hawksworth, the so-called detective, who had deigned to listen to a part of the altercation, at a distance, between Warner and his prisoner. Hawksworth appeared to have been highly amused at the feeble attempt to find out something against this little fellow, who had not, he thought, from what little he had heard, done anything worth noticing, beyond mistaking his way while leaving the tower. This self-sufficient officer was of opinion that the paltry evidence elicited by Warner amounted to very little—there was no proof of his guilt.

“I really,” replied the aeronaut, “have no time or mind to enter just now upon a discussion as to detective theories. Warner, whose intelligence I am ready to support on a more suitable occasion, has taken this man in the act of having committed a trespass, and he is acting not upon ‘vague clues or roundabout rumours,’ but on stubborn facts. I believe that Warner knows perfectly well what he is about, and that the prisoner knows more about this tall confederate than you do probably.”

“Most likely, Mr Goodall,” replied Hawksworth, “for I merely caught a portion of what was said; you mentioned something about a second tall man, sir?”

“I cannot spare time to enlighten you any further, Mr Hawksworth.”

“But this silly, card-sharping looking lad merely said,” whispered the tall detective derisively, “that he came from Sussex—had he hailed from the other side of the world, sir, I should have opened my own eyes.”

“Yes, I have heard that you are expecting two clients from Australia; but we had better stop chatting, there are listeners near us, Mr Hawksworth.”

“You are right, sir, and I am wrong in interfering, perhaps. Kindly excuse me for having blundered.”

“I am afraid you have blundered,” cried Simon Warner, “if you think that little man is guileless, for he looked at you as if he knew you.”

“I am perfectly ignorant as to who he is, or what he is doing here!” exclaimed the detective.