Their rendezvous was at noon, but two hours earlier Tignol took the train at the St. Lazare station.  And with him came Caesar, such a changed, unrecognizable Caesar!  Poor dog!  His beautiful, glossy coat of brown and white had been clipped to ridiculous shortness, and he crouched at the old man’s feet in evident humiliation.

“It was a shame, old fellow,” said Tignol consolingly, “but we had to obey orders, eh?  Never mind, it will grow out again.”

Leaving the train at Auteuil, they walked down the Rue La Fontaine to a tavern near the Rue Mozart, where the old man left Caesar in charge of the proprietor, a friend of his.  It was now a quarter to eleven, and Tignol spent the next hour riding back and forth on the circular railway between Auteuil and various other stations; he did this because Coquenil had charged him to be sure he was not followed; he felt reasonably certain that he was not, but he wished to be absolutely certain.

So he rode back to the Avenue Henri Martin, where he crossed the platform and boarded a returning train for the Champs de Mars, telling the guard he had made a mistake.  Two other passengers did the same, a young fellow and a man of about fifty, with a rough gray beard.  Tignol did not see the young fellow again, but when he got off at the Champs de Mars, the gray-bearded man got off also and followed across the bridge to the opposite platform, where both took the train back to Auteuil.

This was suspicious, so at Auteuil Tignol left the station quickly, only to return a few minutes later and buy another ticket for the Avenue Henri Martin.  There once more he crossed the platform and took a train for the Champs de Mars, and this time he congratulated himself that no one had followed him; but when he got off, as before, at the Champs de Mars and crossed the bridge, he saw the same gray-bearded man crossing behind him.  There was no doubt of it, he was being shadowed.

And now Tignol waited until the train back to Auteuil was about starting, then he deliberately got into a compartment where the gray-bearded man was seated alone.  And, taking out pencil and paper, he proceeded to write a note for Coquenil.  Their meeting was now impossible, so he must fasten this explanation, along with his full report, under Caesar’s collar and let the dog be messenger, as had been arranged.

“I am sending this by Caesar,” he wrote, “because I am watched.  The man following me is a bad-looking brute with dirty gray beard and no mustache.  He has a nervous trick of half shutting his eyes and jerking up the corners of his mouth, which shows the worst set of ugly yellow teeth I ever saw.  I’d like to have one of them for a curiosity.”

“Would you?” said the man suddenly, as if answering a question.

Tignol stared at him.

“Excuse me,” explained the other, “but I read handwriting upside down.”

“Oh!”

“You say you would like one of my teeth?”