"I left an umbrella in a taxi last night, a very superior umbrella, with Mark Ashton engraved on the handle. If you're driving down you might look in at the Lost Property Office and see whether it's turned up." "Right you are," said Colin. "I shall be along in about an hour." He hung up the receiver, and, putting away the Professor's cigar in an inside pocket, donned his hat and coat and proceeded to leave the house. A little way down the hill, in a side mews off Vicarage Gardens, he had discovered a new garage, to which he had recently transferred his patronage. The car was ready for him, and a few minutes later he was seated at the driving wheel, skilfully threading his way through the crowded traffic that renders High Street, Kensington, such a stimulating thoroughfare. Big Ben was in the act of striking three as he arrived at Westminster Bridge. He pulled up outside the entrance to the Lost Property Office, and, pushing open the swing door, advanced to the counter, where a stalwart constable was thoughtfully scratching his head with the stump of a pencil. Having listened in silence to Colin's inquiry, the man got down from his seat and disappeared into the back regions, returning almost immediately with the umbrella in his hand. "You'll have to sign your name here," he announced, pushing forward an official-looking paper. "And there'll be two and sixpence reward for the driver." Without entering upon any superfluous explanations, Colin paid over the desired sum, and, after neatly forging Mark's signature, made his way back to the car. He was leaning over the side door, storing away his trophy, when a gruff voice suddenly addressed him from the pavement behind. "Doctor Gray, unless I'm much mistaken!" Turning round promptly, he found himself face to face with the burly, shrewd-eyed figure of Inspector Marsden. "I thought I was right," continued the detective. "It's part of my business to recognize people by their back view." Colin gripped the large and efficient-looking hand which the speaker extended to him. "I'm awfully glad to see you again," he said heartily. "I hope you're none the worse for that little dust-up in the King's Road?" "Still a bit sore in the ribs," was the answer. "I fancy the beauty who got that kick in must have been a footballer at some time or other in his career. I'll give him football if I ever find out which of 'em it was." "How about our ginger-haired friend?" inquired Colin. "I've been expecting to hear every day that I was wanted as a witness."