Delightful Variation

If I have gone to excessive lengths in spelling out every last detail of the preceding adventure, I have done so for the sake of the reader who is an absolute beginner in the art of chess detection. This was the stage I was in at the time. As I grew more and more adept at this type of reasoning, Holmes could afford to give me shorter and shorter explanations of the solutions to these intriguing problems.

Two evenings later, Holmes and I had a pleasant surprise: an unexpected visit from Colonel Marston and our new acquaintance, Sir Reginald. We were always delighted to see Colonel Marston, who is a keen-witted and most amusing chap. And Sir Reginald we liked more and more as we got to know him better.

After a cozy round of warm brandy, Marston said, "It did not take us very long, Holmes, to figure out your little mystification. Of course, since we were the players, this is not very much to our credit. After all, Holmes, it was I who made that highly unorthodox move of promoting to a bishop. But it took us a bit of thought to realize that from the standpoint of that position, no other last move could have been possible."

Holmes, delighted, arose and said, "I knew you would get it, Marston, I knew you would! And now, gentlemen, I should like to tell you of a curious coincidence. The position which I found when you were playing Sir Reginald bears a striking similarity to the following position I saw two years ago in a club I was visiting in Calcutta." And Holmes set up the chessboard as follows:

North

fi

A

&

if:;

ä

gg& vi^v .. ■• .: ... .. .. .j. ,. .-•• . .:.■■' " il" * "' m

South

"As you see, gentlemen, the only difference is that a pawn is on d6 instead of e5. Yet this little difference is enough to make it totally impossible to tell now which side is White."

We all looked at the board with great curiosity. Marston spoke first. "I really don't see how this change is relevant, Holmes. White's only possible last move is a pawn from g2 capturing a Black piece on h1 and converting to a bishop."

"Not so, Marston; this is a possible last move, but not the only one. When I first saw this position, I had the same immediate thought, and was just about to surprise the players by telling them which side was White when I suddenly realized that there was another equally real possibility. Fortunately, just as one of the players was about to clear the board, I asked him, 'Sir, has any promotion taken place in this game?' His hands stopped as he turned to me and said, 'No, there hasn't, but why do you ask?' 'Because,' I replied triumphantly, 'this means that you must have been playing White!' Both gentlemen looked at me rather amazed, though their amazement turned to amusement when I told them how I knew."

We all looked at the position with greater interest than ever. Marston again spoke. "I can't see it, Holmes; I really can't! Since White's last move was not a promotion, it must have been with one of the pawns on d4 or d6. But in either case, Black could not have had any possible last move!"

"Not so, Marston, not so," replied Holmes. "White's last move was indeed with one of these pawns. I'll even give you a hint and tell you that it was with the pawn on d6."

"But," said Marston, "the pawn must have moved from d5 to give Black check from the bishop on h1. So how could the Black king have moved before that? The only square it could have come from is a7, but this would involve an imag-inary check!"

At this point Sir Reginald spoke up. "Brilliant, Mr. Holmes, really brilliant! I see it now! White moved the pawn not from d5, but from e5 capturing a Black pawn on d5 en passant! This Black pawn had, of course, just moved from d7. White's move before that was with the pawn then on e5 from e4, putting Black in check. And Black's move before that was with the king from a7, moving out of check from the bishop on c5, but not being in check from the queen, since the Black pawn would have been on e7."

"I'm afraid that was a bit hard for me to follow," I remarked. "Would you mind going over it again?"

"Why certainly," replied Sir Reginald. "The position a couple of moves ago was something like this." He rearranged the pieces:

Then he made the following sequence of moves to bring the game to its present position:

3 P x P en passant check

And that's how Holmes knew which side was which!

Was this article helpful?

0 0

Post a comment