"I have the honor to be a detective. In that capacity behold me here." I thought this rather dramatic and Frenchified, and I had the pleasure of seeing her turn white to the lips. "A comrade is on watch outside," I continued. She slipped from the counter to the door, and peering cautiously about, saw Wheeler, who, I being by her side, gave me a nod of recognition. "Are you satisfied, madame?" I asked, when she had taken her place again behind the counter. "There is protection for women in this country," she said. "Are you employed by the Government?" "Fortunately for you I am not. You will, perhaps, understand when I say I am a private detective. If a Government official were in my place it would be with a warrant." "A warrant, monsieur?" "A warrant, madame--for your arrest. Shall we converse here or in your private room?" She moved towards the green curtain. "A moment," I said. "Last night, when I had the pleasure of purchasing some of your very excellent provisions, and happened to mention that I was recommended by Mrs. Fordham, you had a visitor in that room, who gave you a signal. Is the gentleman there now?" "There is no gentleman in the room," she said, throwing open the door. "How know you there was one?" "I shall surprise you, madame, with the extent of my knowledge. In order that we may not be interrupted we will turn the key in the shop door." "You are not afraid?" she asked, and there was a look in her eyes resembling that of a cat who is about to spring. "Oh, no, madame," I replied, following her to the inner room, "the English are not afraid of the French." "Nor the French of the English," she hissed. "You are a brave nation," I said, with a polite bow, "so are we. I propose, in your interests, an alliance." "Not in your own, monsieur?" "Not in my own, madame. I am merely an agent, and am not in any danger. You are a principal." "A principal! What is that?" "Your knowledge of our language, Madame Lourbet, is almost perfect; one might take you for a native, you speak English so fluently. But at your wish I will explain what I mean by my use of the word. It is that of a man or a woman who, without actually committing a crime, aids in its perpetration. "I defy you to prove that I knew of it," she cried. "I have not finished--though your denial, being in the past tense (a point of grammar, madame), is partial proof that it does not apply to the present. By the term 'principal' I mean also a man or a woman who, not being a witness of the crime, assists afterwards in keeping those who are guilty out of the hands of justice, and who, at the same time, assists in fixing that crime upon the innocent. That affects you, madame, and if you persist in shielding the guilty, you will see the inside of a prison door. I am going to be quite plain with you. Some years ago you, being then in Paris, entered the service of a gentlemen who is now in prison on a charge of murder." "I did not. I entered the service of a lady."