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To start with, White has to chase the enemy bishop from the a3-f8 diagonal. That is done by bringing his own bishop to f8, <1. Bc3 Ba3 2. Bg7 Bb4 3. Bf8>. Now the black bishop has to take up a new post along the f8-h6 diagonal, at g7 or h6. If 3 ... Bd2 4. Ba3 Bh6 5. Bb2, Black runs out of constructive moves. His king must give way, 5 ... Kf5, and that fails to 6. Bg7. So he tries <3 ... Bc3 4. Ba3 Bg7 5. Bc1>, but once again Black runs out of moves, and <5 ... Kf6> is met by <6. Bb2+ Kg6 7. Bxg7> winning."

"That same year, 1856, Centurini topped himself with a sustained eleven-move bishop sequence.

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The ending is won if White can bring his bishop to the b8-h2 diagonal, challenging Black for control. That means the bishop must get to c7 or b8. At present Black is solidly guarding c7, so White tries to bring his bishop to b8. That will force the black king over to a6, momentarily weakening his protection of c7. The initial moves are <1. Bh4 Kb6 2. Bf2+ Ka6>. Now comes the key move <3. Bc5!>. Black is forced to make a move with his bishop, and this in turn will provide White with a vital tempo later on. After <3 ... Bg3 4. Be7> White threatens 5. Bd8 and 6. Bc7, thus forcing the black king to abandon a6 and return to c6, <4 ... Kb6 5. Bd8+ Kc6>. The position in the next diagram is almost the same as our starting position, but the black bishop is at g3, not h2. This small difference allows White to pick up a crucial tempo.

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<6. Bh4! Bh2 7. Bf2>, when the bishop is on his way to a7. Black is one move too late to stop it: <7 ... Kb5 8. Ba7 Ka6 9. Bb8>

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Now the black bishop must give way and relocate to a7, which turns out to be a terrible defensive square: <9 ... Bg1 10. Bg3 Ba7 11. Bf2>, and wins. If 11 ... Bxf2 12. b8=Q. And if <11 ... Kb5> we get twelve consecutive moves by the white bishop, <12. Bxa7>."