‘Well, as it happened, Blenkinsop was not at the club, but I found Mr Pusely-Smythe alone in the smaller reading-room. I’ve had to submit to a good deal of chaff—not particularly amusing—from Pusely-Smythe, and by way of return it seemed appropriate that he should help me to win our one hundred and ten pound prize. Also, if he will forgive me for saying so, he has just the commonplace shrewdness that I required in my victim. ‘After a little preliminary conversation, I produced my sovereign-case. I told him that there was a certain sum of money in gold in that case, and that I was willing to bet him a sovereign I would make him a present of it. He said, as I knew he would, that this meant that the sum of money in the case was half a sovereign, and that in consequence he would lose ten shillings on the transaction if he took the bet. ‘“Yes,” I said, “there is that possibility, but I am willing to protect you against it by a second bet. We will agree that the loser by the first transaction shall have the option to give the other man double what he has lost for double the sum now in my sovereign-case. And I will bet you a sovereign that he will not exercise that option. You see how it works out. If the sum in my sovereign-case is half a sovereign, as you suppose, you will lose ten shillings on the first transaction, but you will win a sovereign on the second transaction by exercising an option to exchange twenty shillings for twenty shillings.” ‘Without taking the time to think, he accepted both bets. I then opened my sovereign-case and showed him that it contained two pounds. I gave them to him, and as by so doing I had won my bet he gave me one of them back again. Kindly observe that I had now solved the first part of Leonard’s problem. I had won an even bet of one pound the net result of which was that I had lost a pound. Having made myself the loser on the first transaction, I now had the option to exchange twice my loss against twice the sum that had been in the sovereign-case—that is, to exchange two pounds for four pounds. I had bet that the loser would not exercise this option. I lost the bet and exercised the option. Thus, I lost an even bet of one pound with the net result that I made one pound. This settles the second half of the problem. I await, sir, with confidence, your decision in my favour.’ Mr Matthews referred once more to the terms of the problem. ‘Yes,’ he said, ‘it seems to me that you have met all Leonard’s requirements. Very smart bit of work, in my opinion. You take the club cheque for one hundred and ten pounds, unless, of course, some claim to share it with you is substantiated. Is there any such claim?’ ‘Naturally, there’s mine,’ said Pusely-Smythe, with his deceptive air of melancholy. ‘Yours? How did you do it?’