He set off at a brisk pace in the direction of the Houses of Parliament, and crossing the street I took up a tactful position in his rear.  In this order we proceeded along Whitehall, across Trafalgar Square, and up Charing Cross Road into Coventry Street.  Here George stopped for a moment to buy himself a carnation—­he had always had a taste for buttonholes—­and then resuming our progress, we crossed the Circus, and started off down Piccadilly.

By this time what is known I believe as “the lust of the chase” had fairly got hold of me.  More strongly than ever I had the feeling that something interesting was going to happen, and when George turned up Bond Street I quickened my steps so as to bring me back to my old if rather tempting position close behind him.

Quite suddenly in the very narrowest part of the pavement he came to a stop, and entered a doorway next to a tobacconist’s shop.  In a couple of strides I had reached the spot, just in time to see him disappearing up a winding flight of stone stairs.

There were two little brass plates at the side of the door, and I turned to them eagerly to see whom he might be honouring with a visit.  One was inscribed “Dr. Rich.  Jones, M.D.,” and the other “Mlle. Vivien.”

The moment I read the last name something curiously familiar about it suddenly struck me.  Then in a flash I remembered the pencilled notice on Tommy’s door, and the obliging “Miss Vivien” who was willing to receive his telegrams.

The coincidence was a startling one, but I was too anxious to discover what George was doing to waste much time pondering over it.  Stepping forward to the foot of the stairs, I peered cautiously up.  I could see by his hand, which was resting on the banisters, that he had passed the floor above, where the doctor lived, and was half way up the next flight.  Whoever Mlle. Vivien might be, she certainly represented George’s destination.

I retreated to the door, wondering what was the best thing to do.  My previous effort in Victoria Street had been so successful that I instinctively glanced across the street to see whether there was another convenient restaurant from which I could repeat my tactics.  There wasn’t a restaurant but there was something else which was even better, and that was a small and very respectable-looking public-house.

If I had to wait, a whisky-and-soda seemed a much more agreeable thing to beguile the time with than a third helping of ham and eggs, so crossing the road with a light heart, I pushed open a door marked “Saloon Bar.”  I found myself in a square, comfortably fitted apartment where a genial-looking gentleman was dispensing drinks to a couple of chauffeurs.

Along the back of the bar ran a big fitted looking-glass, sloped at an angle which enabled it to reflect the opposite side of the street.  This was most convenient, for I could stand at the counter with my back to the window, and yet keep my eye all the time upon the doorway from which George would appear.