“I don’t see . . .” Francis began. “The postmark, man, the postmark!” cried Desmond. Francis turned to the envelope again. The postmark was unusually clear. It read: [Illustration: ST JOHN’S WOOD NW8, 6 PM 23 MAR 1923] “Yesterday’s date!” said Francis. “I found that letter in the drawer of the typewriting table. It was posted at Saint John’s Wood before six o’clock yesterday evening,” Desmond exclaimed emphatically. “It was, therefore, delivered here by the last post. Now what time is the last delivery in London?” “Nine o’clock . . .” began Francis. Then broke off. “By George, Des.,” he said slowly. “I take my hat off to you. You can give us all points. Of course, this letter knocks the bottom out of old Farandol’s theory. The girl was alone in the flat, therefore to take this letter from the postman she must have been alive at 9 P.M., therefore the murder did not take place while Hollingway was here, that is to say, before eight-twenty. Unless Hollingway came back . . .” “That,” said his brother, “Webb, the porter, must tell us. Here he is, I think!” Webb was a forlorn-looking old man with a shining bald pate and a haggard face intersected with blue veins. “Come in, Webb,” said Desmond, advancing to the front hall to meet him. “I want you to answer one or two questions. What time did Captain Hollingway leave here last night?” “Captain ’Ollingway?” queried the old man. “Yes, the gentleman that brought Miss Bardale home.” The old man appeared to think. “It wor about twenty-five minutes past h’eight, Mister!” “How do you know the time so exactly?” demanded Desmond. Old Webb cast him a sly look. “’Cos for why from where I sets in the front ’all I kin ’ear the clock on Saint Jude’s strike. The quarter ’adn’t long gorn and the ’arf ’adn’t struck w’en the Capting come out. ‘Wish you good-night, Capting,’ I sez . . .” “But why should you have noted the time so carefully?” Desmond broke in impatiently. Old Webb’s rheumy eyes puckered up as a cunning grin slowly broke out over his face. “I was a-waitin’ for my supper-beer,” he replied. “The gal brings it every night at ’arf-past h’eight!” Desmond smiled. “I see!” he said. “Were you on duty in the hall all the evening?” he asked. “I wor, sir, till midnight, w’en I locks up, same as allus!” “And you never left the hall?” “No, sir!” “Did Captain Hollingway come back?” “No, sir!” “You’re sure?” “There worn’t nobody come the whole dratted evenin’ arter ’im, only the pos’man!” “Oh, the postman came eh? At what time?” “Round about nine o’clock or a bit arter!” “Do you take the letters up or does he?” “’E do! I can’t get around much along o’ my bad leg!” “Do you know if there were any letters for Miss Bardale?” “I dunno nothink about that!” “Did the postman say anything?” “’E wor put out ’cos, ’e said, there wor but the one letter and ’e ’ad to carry it to the very top!” “To Miss Bardale’s, you mean?”