Then he added: “She wore only one ornament, a beautiful piece of apple-green jade suspended round her neck by a narrow black ribbon. When they rose and the waiter brought their coats, I heard him call her Dorothy.”

“Dorothy Cullerton!” I gasped. “I recollect that piece of Chinese jade she wore in Florence! What is she doing here, meeting that man clandestinely?”

“The man slipped something into her hand beneath the table and she put it into her handbag,” Hambledon said. “I have a suspicion that it was a small roll of French bank notes.”

“Payment for some information, perhaps,” I said. “I don’t trust that young stockbroker’s wife. Well?” I asked. “And what then?”

“On leaving the Rotonde they drove to the Rue de Rivoli, where the lady alighted and entered the Hôtel Wagram, while he went along to the Hôtel du Louvre,” was his reply.

I was much puzzled at the secret meeting between the affable Frenchman and young Mrs. Cullerton, and next day by watching the entrance to the Hôtel Wagram, which was an easy matter in the bustle of the Rue de Rivoli, I satisfied myself that my surmise was correct, for at eleven o’clock she came forth, entered a taxi, and drove away.

My next inquiry was at the head office of the Crédit Lyonnais, in the Boulevard des Italiens, but, as I suspected, the name of my French fellow-traveller was unknown.

“We have no official of the name of Suzor,” replied the polite assistant director whom I had asked to see. “The gentleman must be pretending to be associated with us, monsieur. It is not the first time we have heard of such a thing.”

So it was apparent that Suzor was not a bank official after all!

In the meantime Hambledon was keeping watch at the Hôtel du Louvre, and it was not until afternoon that he rejoined me to report what had occurred.