“Walk,” said Tab promptly. “Only the detectives of fiction take cabs, Carver. The real people know that when they present their cab bills to the head office, a soulless clerk will question each item.” “Tab, you certainly know more about the interior economy of thief-catching than an outsider ought to know,” responded the detective gloomily. Between them and Trasmere’s house was the better part of a mile. Mayfield, the dwelling place of old Jesse, was the one ugly building in a road which was famous for the elegance of its houses. Built of hideously yellow brick, without any attempt at ornamentation, it stood squat and square in the middle of a cemented “garden.” Three microscopic circles of earth had been left at the urgent request of the builder, wherein Mr. Jesse might, if he so desired, win from the sickly earth such blooms and blossoms as might delight his eye. To this he reluctantly agreed, but only after there had been pointed out to him the fact that such an alteration to his plans would save a little money. “It isn’t exactly the Palace of the Fairy Prince, is it?” said Tab, as he pushed open the cast iron gate. “I’ve seen prettier houses,” admitted Carver, “I wonder--” So far he got, when the front door was flung violently open and Rex Lander rushed out. His face was the colour of chalk, his big baby eyes were staring wildly. They fell upon the two men on the concrete walk and his mouth opened to speak, but no words came. Tab ran to him. “What is wrong?” he demanded and that something was badly wrong one glance at Babe Lander told him. “My uncle,” he gasped. “Go look.” Carver rushed into the house and through the open door of the dining-room. It was empty, but at the side of the fireplace was a narrower door. “Where is he?” asked the detective. Rex could only point to the narrow aperture. There was a flight of stone stairs which terminated in a narrow passage, barred by yet another door, which was also open. The corridor was well-lighted by three globes set at intervals in the ceiling, and the acrid smell of exploded cordite filled the confined space of the passage, which was empty. “There must be a room opening from here,” said Carver, “whose are these?” He stooped and picked up an old pair of gloves that lay on the floor and pushed them into his pocket. He looked round for Rex Lander. That young man was sitting on the top step of the stairs, his face in his hands. “There’s no sense in questioning him,” said Carver in an undertone, “where is his uncle?” Tab walked rapidly down the passage and came to a door on the left. It was a narrow door painted black, and deeply recessed in the thick wall. There was no handle and only a tiny keyhole. Four inches from its top was a steel plate pierced with small holes for the purpose of ventilation. He pushed the door, but it was locked. Then he peered through the ventilator.