Chu-Chu's taxi was of precisely the same make and model as Rosali's, the sort most in use in Paris. But from the way he passed us I could see that he was getting a good deal more out of his motor than we were—and this was not surprising when you come to remember that Chu-Chu was a star driver, with a beautiful sense for any sort of machinery, whereas Rosalie was more or less of a novice. Besides, her carburetter was working irregularly, and she was always too impatient about going into the speed ahead. I was afraid that as soon as we struck the fast part of the road beyond St. Cloud Chu-Chu might dig out and leave us wondering. There was also the chance of his be coming suspicious of us if at the end of several kilometres he found us still on his trail. Rosalie's taxi looked like any other taxi, but Rosalie herself did not look like any other taxi driver, and what had been at first an advantage—for Chu-Chu would never suspect me of picking out the most conspicuous driver in Paris to hound him—might easily spoil the whole business.
So I picked up the speaking tube. We were working up the last easy part of the grade.
"Madame Rosalie," I said.
"Eh, well?" she answered.
"I'm afraid he smells a rat. He is going to try to leave us once we get past the railroad crossing."
"Don't be afraid," she answered tartly. "There isn't a taxi in Paris that can make this one feel lonely. Besides, he is carrying one more person."
"But how about your carburetter?"
