### Writing Tip for Today: Dominoes

A domino is a small rectangular block, the face of which is divided into two parts, each either blank or bearing from one to six pips (or dots) that resemble those on dice. 28 such pieces form a complete set. The word also refers to the various games played with such pieces. Dominoes can be placed edge to edge in lines and angular patterns to develop snake-line chains of value, or they may be stacked into towers or pyramids. Some sets of dominos use more readable Arabic numerals instead of pips to indicate the values of the ends of each piece.

A dominant, or leading, domino is the tile that begins the chain. The player who draws the most valuable domino for his hand has first choice of playing it. In some games, a domino cannot be played until all the other players have drawn their hands. In other cases, a domino must be played to a double in the same fashion that a double is played to an empty place.

Once a domino has been positioned in this way, the other players must follow it with a play of their own. If a player does not have a domino of the appropriate value in his hand, he must draw another domino from the boneyard and add it to his stack. If a player draws more for his hand than he is entitled to, this excess is called an overdraw. This surplus is then added to the winning total for that game.

The physics of dominos is quite interesting. When a domino is standing upright, it stores potential energy based on the position of its edges. When the domino falls, however, much of this potential energy is converted to kinetic energy in the chain reaction that causes domino after domino to fall. This type of energy is often referred to as the “domino effect.”