|---------------------------------------|
3 | | | | | | | ^P | |
|---------------------------------------|
2 | ^P | ^P | | | | | | ^P |
|---------------------------------------|
1 | | | | | | | ^K | |
+---------------------------------------+
a b c d e f g h

DIAGRAM 42.

White on the move can force the mate by (1) R-d8, a very
surprising sacrifice indeed, for not only can Black take the Rook
with either Queen or Rook but he can also take White's Queen. In
the latter case, however, he would be mated in two moves by (2)
Rxe8+, Q-g8; (3) Kt-f7. This is one example of the "throttled
mate" by the Knight. Another one, which is really the typical
one, occurs if Black takes the Rook instead of the Queen. The
mating process then is: (2) Kt-f7+, K-g8; (3) Kt-h6 double check,
K-h8; (4) Q-g8+, Rxg8; (5) Kt-f7+/-. White could not have played Q-
g8+ right on the second move because then Black would have taken
the Queen with the King, while he could not do so with White's
Knight on h6.

Sacrifices made with the view of a direct mating attack are, as a
rule, the easiest to figure out, as there is no guesswork
connected with them. In those cases the player does not face the
question as to whether the position attained after the sacrifice
will be strong enough to insure a gain of material at least
equivalent to the amount of material sacrificed, a question which