---------------------------------------
8 | | | | #R | | #R | #K | |
|---------------------------------------|
7 | #P | #P | | | | #P | #P | #P |
|---------------------------------------|
6 | | | #P | | #P | | | |
|---------------------------------------|
5 | | | | | | | | |
|---------------------------------------|
4 | | | | ^P | | | | |
|---------------------------------------|
3 | | | | | | | | |
|---------------------------------------|
2 | ^P | ^P | ^P | | | ^P | ^P | ^P |
|---------------------------------------|
1 | | | ^K | ^R | | | | ^R |
---------------------------------------
A B C D E F G H

Diag. 3.

must be met in some way or other. This can be done by capturing
the attacker or by interposing a piece (this is not possible in
case of attack by a Knight or a pawn), or lastly by moving the
King to a square which is not attacked. The latter must not be
done by castling. If it is impossible by any of the three methods
above mentioned to avoid the attack upon the King, the King is
said to be checkmated, and the game is ended.