nt of which we
have the secret."

M. de Cassaud was doubtful about the propriety of such a procedure.

"After all I found them," Martin urged.

"It would be unusual," said M. de Cassaud. "The regulations, you
know----"

Martin Hillyard smiled.

"The regulations, for you and me, my friend, are those we make
ourselves."

M. de Cassaud would admit nothing so outrageous to his trained and
rather formal mind. But he made a list of these letters and of their
addresses as though he was undecided. He had not finished when a
sergeant entered and saluted. The attendant of the sleeping-car had been
taken to the depot. He had been searched and a pistol had been found
upon him. The sergeant laid a very small automatic Colt upon the table
and retired. M. de Cassaud took up the little weapon and examined it.

"Do you know these toys, Monsieur Hillyard?" he asked.

"Yes. They are chiefly used against the mosquitoes."

"Oh, they will kill at twenty-five paces," continued the Commissaire;
and he looked quickly at Hillyard. "I will tell you something. You ran
some risk last night when you explored that water-tank. Yes, indeed! It
would have been so easy. The attendant had but to thrust the muzzle of
this through the opening of the window, shoot you dead, raise an alarm
that he had caught you hiding something, and there was he a hero and you
a traitor. Yes, that is why I said to you the little opening in the
window was ingenious! Ah, if he had caught you! Yes, if he had caught
you!"

Martin was quick to take advantage.

"Then let me have those letters! I will keep my French colleagues
informed of everything."

"Very well," said M. de Cassaud, and he suddenly swept the letters
across to Hillyard, who gathered them up hastily and buttoned them away
in his pocket before de Cassaud could change his mind.

"It is all very incorrect," said the Commissaire reproachfully.

"Yes, but it is the war," replied Hillyard. "I have the authority of the
attendant of the sleeping-car for saying so."

CHAPTER XVI

TRICKS OF THE TRADE

"Now!" said Hillyard.

Fairbairn fetched a couple of white porcelain developing dishes to the
table. Hillyard unlocked a drawer in his bureau. They were in the
deck-saloon of the _Dragonfly_, steaming southwards from Valencia.
Outside the open windows the brown hill-sides, the uplands of olive
trees and the sun-flecked waves slipped by in a magical clear light; and
the hiss of the beaded water a