When in his turn Rust sought diffidently to penetrate the mystery surrounding Madame Gilbert, she overflowed with untruthful particulars. She resembles her master Dawson in this--it is unwise to believe one word which she wishes you to believe. Of her early life in Paris she spoke with emotion. She was the beloved only child of a French doctor--ah, the most learned and pious of men! He died early smitten by disease contracted during his gratuitous practice amongst the friendless poor. A most noble parent! Her mother, too, a saint and angel, had gone aloft shortly after seeing her daughter, Madame, happily married to a maker of calorifères (anthracite stoves). "I am unworthy of those so noble parents," wailed Madame in broken tones. It was not until they were about to separate that Madame Gilbert herself threw him a bone of truth designed to test his appetite for curiosity. "I must fly," exclaimed she; "I am a woman _très occupée_. I work, oh, so very hard, for my belle France and to avenge the death of my glorious husband." The blown-up stove maker did not seem to Rust to be a figure of glory, yet he forced himself again to express the deepest sympathy. "Yes," went on Madame, "I would avenge him. I work,"--she glanced round cautiously, and then whispered--"I work for the _gouvernement anglais_. I am an _agent de police_." "Were you not rather rash," I asked of Madame Gilbert, "to give yourself away so completely? He might not have been so thorough an ass as you thought." "My friend," said Madame calmly, "I had taken tea with him twice, and had satisfied myself that he was not, what you call, very bright. A dear fellow, handsome, a gentleman of the English pattern, but not bright. If I had not helped him to get a move on, I might have lunched with him, had tea, dined with him, attended theatres, traversed in motors your pleasant countryside, flirted, until I had become a very old woman, and there would have been nothing to show for all my exertions. I remembered the instructions of Mr. Dawson, I recalled to myself my duty, I was compelled to discover who and what was this Capitaine Rouille, and I could only succeed by forcing him to reveal himself--to give himself away. When I said that I was an agent of the English police, he did not believe me; but he was curious--he watched me. I gave him much to watch and to imagine that he had discovered. Then one began to get forward." * * * * *