Michael took the slip of paper. It was identically worded with its predecessor. “Is your trouble of mind or body incurable? Do you hesitate on the brink of the abyss? Does courage fail you? Write to Benefactor, Box——” “There will be no reply till to-morrow morning. Letters are to be readdressed to a shop in the Lambeth Road, and the chief wants you to be ready to pick up the trail.” The trail indeed proved to be well laid. At four o’clock on the following afternoon, a lame old woman limped into the newsagent’s shop on the Lambeth Road and inquired for a letter addressed to Mr. Vole. There were three waiting for her. She paid the fee, put the letters into a rusty old handbag and limped out of the shop, mumbling and talking to herself. Passing down the Lambeth Road, she boarded a tramcar _en route_ for Clapham, and near the Common she alighted and, passing out of the region of middle-class houses, came to a jumble of tenements and ancient tumble-down dwellings. Every corner she turned brought her to a street meaner than the last, and finally to a low, arched alleyway, the paving of which had not been renewed for years. It was a little cul-de-sac, its houses, built in the same pattern, joined wall to wall, and before the last of these she stopped, took out a key from her pocket and opened the door. She was turning to close it when she was aware that a man stood in the entrance, a tall, good-looking gentleman, who must have been on her heels all the time. “Good afternoon, mother,” he said. The old woman peered at him suspiciously, grumbling under her breath. Only hospital doctors and workhouse folk, people connected with charity, called women “mother”; and sometimes the police got the habit. Her grimy old face wrinkled hideously at this last unpleasant thought. “I want to have a little talk with you.” “Come in,” she said shrilly. The boarding of the passage-way was broken in half a dozen places and was indescribably dirty, but it represented the spirit of pure hygiene compared with the stuffy horror which was her sitting-room and kitchen. “What are you, horspital or p’lice?” “Police,” said Michael. “I want three letters you’ve collected.” To his surprise, the woman showed relief. “Oh, is that all?” she said. “Well, that’s a job I do for a gentleman. I’ve done it for years. I’ve never had any complaint before.” “What is his name?” “Don’t know his name. Just whatever name happens to be on the letters. I send ’em on to him.” From under a heap of rubbish she produced three envelopes, addressed in typewritten characters. The typewriting Michael recognized. They were addressed to a street in Guildford. Michael took the letters from her handbag. Two of them he read; the third was a dummy which he himself had written. The most direct cross-examination, however, revealed nothing. The woman did the work, receiving a pound for her trouble, in a letter from the unknown, who told her where the letters were to be collected.