"He hasn't; but I have. The telephone number which figures in the case is the number of a pay station in an all-night drug store in Washington. Westerfeltner freely gave me the number. Both the proprietor of this drug store and his clerk remember that night before last, shortly before eight o'clock, a rather small, slight woman wearing a black street costume with a dark veil over her face came into the place and said she was expecting a telephone call for Mrs. Williams. Within two or three minutes the bell rang and the clerk answered and somebody asked for Mrs. Williams. The woman entered the booth, came out almost immediately, and went away. All that the drugstore man and his clerk remember about her is that she was a young woman, plainly dressed but well-groomed. The druggist is positive she had dark hair; the clerk is inclined to think her hair was a deep reddish-brown. Neither of them saw her face; neither of them remarked anything unusual about her. To them she was merely a woman who came in to keep a telephone engagement, and having kept it went away again. So, having run into a blind alley at that end of the case, I started in at the other end of it to find the one lady to whom naturally the chief conspirator would turn for help in the situation that confronted him when he ran away from Washington. And I found her--both of her in fact." "Both of her! Then there are two women involved?" "No, only one; but which one of two suspects she is I can't for the life of me decide. I know who she is, and yet I don't know. I'll come to that part of it in a minute or two. I haven't told you the name of the head devil of the whole intrigue yet, have I? You've met him, I imagine. At any rate you surely have heard of him. "You know him, or else you surely know of him, as the Hon. Sidney Bertram Goldsborough, of London, England, and Shanghai, China." "Goodness gracious me!" In her astonishment Miss Smith had recourse to an essentially feminine exclamation. "Why, that does bring it close to home! Why, he is among the persons invited to my cousin's house to-morrow night. I remember seeing his name on the invitation list. That's why you asked me about her party a while ago. My cousin met him somewhere and liked him. I've never seen him, but I've heard about him. A big mining engineer, isn't he?"