“Yes.”

“Game for a morning drive?”

“Certainly.”

“Then dress. No one is stirring yet, but I know where the stable-boy sleeps, and we shall soon have the trap out.” He chuckled to himself as he spoke, his eyes twinkled, and he seemed a different man to the sombre thinker of the previous night.

As I dressed I glanced at my watch. It was no wonder that no one was stirring. It was twenty-five minutes past four. I had hardly finished when Holmes returned with the news that the boy was putting in the horse.

“I want to test a little theory of mine,” said he, pulling on his boots. “I think, Watson, that you are now standing in the presence of one of the most absolute fools in Europe. I deserve to be kicked from here to Charing Cross. But I think I have the key of the affair now.”

“And where is it?” I asked, smiling.

“In the bath-room,” he answered. “Oh yes, I am not joking,” he continued, seeing my look of incredulity. “I have just been there, and I have taken it out, and I have got it in this Gladstone bag. Come on, my boy, and we shall see whether it will not fit the lock.”

We made our way down-stairs as quietly as possible, and out into the bright morning sunshine. In the road stood our horse and trap, with the half-clad stable-boy waiting at the head. We both sprang in, and away we dashed down the London Road. A few country carts were stirring, bearing in vegetables to the metropolis, but the lines of villas on either side were as silent and lifeless as some city in a dream.

“It has been in some points a singular case,” said Holmes, flicking the horse on into a gallop. “I confess that I have been as blind as a mole, but it is better to learn wisdom late than never to learn it at all.”