Wednesday, March 20, 2013

Knight Sacrifice

In a game of speed chess, I sacrificed my knight to mate in fourteen moves.  My opponent, who played black, was Lonnavenue of the USA.  Here are the moves of the game along with my commentary:

1. e4 e5
2. Nf3 c6

Black's move is a surprise.  The move Nc6 is very common here.  I suspect black plans d5 with the aim of a strong pawn centre, but the immediate d5 leaves e5 unprotected.

3. Bc4 Qe7

Black protects e5, but this locks in the king bishop.  The move d6 is better.

4. 0-0 Nf6
5. d4 d5
6. exd cxd
7. Bb3 e4

Black has a strong pawn centre, but his king is in the centre and my knight now has a nice square.

8. Ne5 Qd8

Black moves his queen so that he can free the king bishop and then castle.

9. Bg5 Be7
10. Nxf7 Kxf7

I sacrifice my knight.  This prevents black from castling and begins an attack on the kingside.

11. Bxf6 gxf6

I capture the knight because I want to check with my queen on h5.  Black makes a bad move.  The capture Bxf6 is better because it doesn't weaken the kingside.

12. Qh5+ Kf8
13. Bxd5 Qe8

I have control of the light squares.  Black wants to exchange queens, but I have mate in one.

14. Qh6#

Black's eleventh move, gxf6, weakens his kingside and allows me a quick victory.  Another mistake, but not as critical, is his third move, Qe7.  This move locks in the king bishop and prevents black from castling quickly.  My control of the light squares and ability to shatter the black kingside give me mate in fourteen.

Saturday, March 16, 2013

Papal Names

For the first five centuries, popes used their birth names.  However, it is now the custom for popes to choose a name after their election.  As part of tradition, Peter, the name of the first pope, is not chosen.

The ten most common papal names are the following:

John, Gregory, Benedict, Clement, Innocent, Leo, Pius, Stephen, Boniface, Urban.

Double names are an innovation.  The first pope to take a double name was Pope John Paul I in 1978.

Wednesday, March 13, 2013

Metric and Imperial Systems

The metric and imperial systems are very different from one another.  The metric system is the one used by most countries, but the imperial system is the system which was used by the British Empire.  It is still used in the USA.

In the metric system, one kilometre is one thousand metres and one kilogram is one thousand grams.  However, in the imperial system, one mile is 5280 feet and one pound is sixteen ounces.

The metric system also has metres and centimetres.  One meter consists of one hundred centimetres.  In the imperial system, one yard consists of three feet and one foot consists of twelve inches.  The metric system is based on the decimal system.  The imperial system is not.

The metric system is undoubtedly easier to use than the imperial system.  However, those who are familiar with the imperial system often find it difficult to switch to metric.  In Canada, the metric system is official, but many people still use imperial weights and measures in their daily lives.

Tuesday, March 5, 2013

Opponent Blunders

The blunders of my opponent in a game of speed chess enabled me to mate in 18 moves.  My opponent who played black was Dragstar of Serbia.  Here are the moves of the game along with my commentary:

1. e4 e5
2. Nf3 Nf6
3. Nxe5 Qe7

Black usually plays d6 here.

4. d4 d6
5. Nc4 b5

Black attacks my knight again, but this pawn move is committal.  It is better to regain material equality with Nxe4.

6. Ncd2 Bg4

Black makes a bad move.  Now I can attack the black bishop and protect my e-pawn on my next move.  The move Nxe4 is better.

7. f3 Bd7

Now black cannot capture the e-pawn.

8. Bd3 Nc6
9. c3 a6
10. 0-0 Nh5
11. Nb3 g5
12. f4 gxf

The black knight is unprotected.  A better move is Nf6.

13. Qxh5 0-0-0
14. Bxf4 h6
15. a4 bxa

With the black queenside already quite exposed, black must not allow me to open the position more.  A better move for black is Na7.

16. Bxa6+ Kb8

The black king has inadequate protection.  Now black cannot prevent mate.

17. Qb5+ Ka7
18. Qb7#

Black makes two blunders in this game.  The first blunder is gxf on the twelfth move, a move which leads to the loss of the knight on h5.  The second blunder is on the fifteenth move, bxa, which exposes the king to a decisive attack.  Both blunders in this game are captures.  This game illustrates that captures are sometimes inferior moves.