We walked on for about a quarter of an hour in silence in the trail of the mysterious milkman. He walked quicker and quicker, and we had some ado to keep up with him; and every now and then he left a splash of milk, silver in the lamplight. Suddenly, almost before we could note it, he disappeared down the area steps of a house. I believe Rupert really believed that the milkman was a fairy; for a second he seemed to accept him as having vanished. Then calling something to me which somehow took no hold on my mind, he darted after the mystic milkman, and disappeared himself into the area. I waited for at least five minutes, leaning against a lamp-post in the lonely street. Then the milkman came swinging up the steps without his can and hurried off clattering down the road. Two or three minutes more elapsed, and then Rupert came bounding up also, his face pale but yet laughing; a not uncommon contradiction in him, denoting excitement. “My friend,” he said, rubbing his hands, “so much for all your scepticism. So much for your philistine ignorance of the possibilities of a romantic city. Two and sixpence, my boy, is the form in which your prosaic good nature will have to express itself.” “What?” I said incredulously, “do you mean to say that you really did find anything the matter with the poor milkman?” His face fell. “Oh, the milkman,” he said, with a miserable affectation at having misunderstood me. “No, I--I--didn't exactly bring anything home to the milkman himself, I--” “What did the milkman say and do?” I said, with inexorable sternness. “Well, to tell the truth,” said Rupert, shifting restlessly from one foot to another, “the milkman himself, as far as merely physical appearances went, just said, 'Milk, Miss,' and handed in the can. That is not to say, of course, that he did not make some secret sign or some--” I broke into a violent laugh. “You idiot,” I said, “why don't you own yourself wrong and have done with it? Why should he have made a secret sign any more than any one else? You own he said nothing and did nothing worth mentioning. You own that, don't you?” His face grew grave. “Well, since you ask me, I must admit that I do. It is possible that the milkman did not betray himself. It is even possible that I was wrong about him.” “Then come along with you,” I said, with a certain amicable anger, “and remember that you owe me half a crown.” “As to that, I differ from you,” said Rupert coolly. “The milkman's remarks may have been quite innocent. Even the milkman may have been. But I do not owe you half a crown. For the terms of the bet were, I think, as follows, as I propounded them, that wherever that milkman came to a real stop I should find out something curious.” “Well?” I said. “Well,” he answered, “I jolly well have. You just come with me,” and before I could speak he had turned tail once more and whisked through the blue dark into the moat or basement of the house. I followed almost before I made any decision.