Black to move
The diagram is upside down (Black on bottom).
This lesson series was created for Chess Mentor by Thomas Wolski. It contains many lessons from the games of Wilhelm Steinitz. In addition to enjoying the tactics practice, I am becoming impressed with Wolski's ability to extract lessons from Steinitz's play. I am beginning to think that a more sustained study of the first official World Champion's games might be in my future.
I spotted the first several moves of this combination in one second, that is, instantly. This instant recognition of most of the solution, and the confidence that the rest would be forthcoming stemmed from having seen essentially the same ideas in two other problems that I put in front of youth players in the past two weeks. See "Carlsen's Queen Sacrifice," problems 3 and 6.
This instant recognition strikes me as evidence of pattern recognition as an element in the development of chess skill (see "Patterns and Calculation").