Monday 30 June 1997
The total uselessness of 32 black-squared bishops raises the question of what precisely is the optimum number of same-coloured bishops. The above study by Alexei Troitsky (first published in 1905) gives a surprising example in which five of them come in handy. It is White to play and win.
At first glance, it looks impossible, because White has only his king that can control a white square.
There is only one hope: to persuade Black to advance his pawn to a2, then force him to play Ka1 when White has a bishop on the long diagonal and his king on c3. White will then be able to play Kc2 mate. For this to work, however, he will need a bishop on a1 to prevent the black pawn from advancing there itself.
OK, here goes: 1.B(c7)e5 a5 (or 1...Ka2 2.Kc2 a5 3.Ba1 a4 4.B(b8)e5 a3 5.Kc3 leading back to the main line) 2.Ba1 a4 3.B(b8)e5 Ka2 (best) 4.Kc2 a3 5.Kc3! (necessary to prevent stalemate) 5...Kxa1 6.Kb3+ Kb1 7.Ba1 a2 8.Kc3 Kxa1 9.Kc2 mate!
The remarkable thing is that White needs all five of his bishops: two have to be sacrificed on a1, one is needed to cover the c1 square, a fourth has to lurk on the a3-f8 diagonal to prevent Black's king from moving to a3 at a crucial moment, and the last one has to be in place on the long diagonal to deliver the final discovered mate.
We all know about the power of major pieces tripled on an open file. This position is the only known example of bishops tripled on an open diagonal.
Most expensive city to live in for expatriates: Luanda, Angola takes number one spot with Hong Kong and Zurich in top three
If Surrey were Syria: Social experiment shows what it's like to live under siege
Video of Irish 'professional boxer' fighting Istanbul neighbourhood goes viral in Turkey
Irish tourist filmed fighting with shopkeepers in Turkey says they 'messed with the wrong man'
House of Lords: Outcry as donors, fixers and MPs caught up in expenses scandal get peerages
- 1 Hair loss explained: How and why men go bald
- 2 Game of Thrones season 6: Jon Snow theorists believe the Stark may have a twin sister
- 3 Artist takes LSD, draws herself over different stages of the 9-hour trip to show its effects
- 4 A pint of water every day is the key to losing weight, scientists say
- 5 Russia 'accidentally reveals' number of its soldiers killed in eastern Ukraine
COMPETITIVE + Excellent Benefits: Guru Careers: A Lead Systems Developer / Sof...
Negotiable: Recruitment Genius: The world's leading financial services careers...
£28000 - £30000 per annum: Recruitment Genius: The Digital Marketing Executive...
40-45K DOE + Benefits: Guru Careers: An Account Manager / Senior Account Manag...