I entered the booking-office, searching it with eager eyes. Two lines of persons were taking tickets at the pigeon-holes, while a number of loungers were, like myself, awaiting friends. Beyond, upon the platform, all was bustle as is usual at that hour, when the belated portion of business London is bound for the southern suburbs. From that busy terminus of the West End trains were arriving and departing each minute. The big illumined clock showed that it was yet five minutes to the hour. Therefore I strolled out upon the platform, lounged around the bookstalls, and presently returned to the spot indicated in the letter. As I re-entered the booking-office my eager eyes fell upon a figure standing before me--a well-dressed figure, with a face that smiled upon me. An involuntary cry of surprise escaped my lips. The encounter was sudden and astounding; but in that instant, as I rushed forward to greet the new-comer, I knew myself to be on the verge of a startling and remarkable discovery. CHAPTER TWENTY FIVE. THE PERSON WHO KNEW. The encounter was a startling one. At the moment when my eyes first fell upon the figure standing patiently in the booking-office awaiting me, I halted for a second in uncertainty. The silhouette before me was that of a youngish, brown-haired, and rather good-looking woman, neatly dressed in dead black, wearing a large hat and a feather boa round her neck. By the expression of her face I saw that she had recognised me. I had, of course, never seen her before, yet her personal appearance--the grey eyes and brown hair--were exactly similar to those described so minutely on several occasions by West, the cab-driver. I regarded her for a moment in silent wonder, then advanced to meet her. She was none other than the unknown woman who had saved my life on that fateful night at The Boltons--the mysterious Edna! As I raised my hat she bowed gracefully, and with a merry smile, said: "I fear that, to you, I am a stranger. I recognise you, however, as Mr Heaton." "That is certainly my name," I responded, still puzzled. "And you-- well, our recognition is, I believe, mutual--you are Edna." She glanced at me quickly, as though suspicious. "How did you know that?" she inquired. "You have never seen me before. You were totally blind on the last occasion we met." "I recognised you from your description," I answered with a light laugh. "My description!" she echoed in a tone of distinct alarm. "Yes, the description given of you by the cabman who drove me home on that memorable morning." "Ah! Of course," she ejaculated in sudden remembrance. Then, for a few seconds, she remained in silence. It seemed as though the fact that I had recognised her had somewhat confused her. "But I am extremely glad that we have met at last," I assured her. "I have, times without number, hoped to have an opportunity of thanking you for the great services you once rendered me."