He leaned forward and glanced over the paper, as he responded: "Eight francs and nine centimes." "What did you sell that brought 23 centimes?" asked the colonel with a scrutinizing gaze. "Are you sure that 23 meant centimes?" The man's face paled, and for the first time he hesitated to reply promptly. The colonel gave him no time to collect his thoughts. "What does the X stand for following 23?" "Ten." "Ten what?" "The profit I made." "On what? On the 8.90?" "Yes," was the relieved reply. "Put him under guard," ordered the colonel. As the man was led away, Ralph said: "While he is dressed differently, and appears to look somewhat unlike the peddler we spotted, I think it is the same man," said Ralph. "That pack might show something. Do you object if we take out all the things?" asked Alfred. "Of course not; that fellow is guilty; I am sure of that," said the colonel. [Illustration: _The Spy's Account Book_] The goods were unpacked. In the bottom, neatly folded, was the identical suit that the peddler wore when the boys first noticed him. "He simply shifted suits somewhere in the grounds, and altered his personal appearance. I regard that as very clever, on your part, boys, and the service shall be rewarded," said the colonel. "Now, tell me about your adventures since you left Dunkirk." For an hour the boys were busy telling the colonel about their experiences, their work in the aerial corps, and in the artillery, to all of which he listened with the most intense interest. At the close of the interview the colonel said: "Where are you now staying?" "Anywhere, and nowhere," said Ralph, with a laugh. "Well, you are entitled to a comfortable place, and you shall have it right here. The orderly will see that you are well taken care of; here, Cameron, put up the boys and see that they get anything they want." "Thank you," replied both. As they were passing out the door, an officer was about to enter. "One moment, boys; this is Captain Rose, in charge of the Secret Service. We have had an interesting experience since you left this morning, Captain. Go over to the quarter with the boys and they will tell you about it, for I shall depend on your co-operation to convict the fellow." CHAPTER IX THE LAWS AGAINST SPIES "Did you notice the colonel said that we could have anything we wanted?" said Ralph, after they were once installed in their room in a wing of the building where the officers were sheltered. "I hope he won't forget it," said Alfred. "Tell him we want to be assigned to the artillery branch." "Perhaps we ought to wait until we get through with the peddler, as Captain Rose said the case would come up in the morning," replied Ralph. "Too bad we haven't told Joe. I wonder where he puts up? Maybe the captain knows," said Alfred.