Balkline and straight rail

Balkline (sometimes spelled balk line or balk-line) is the overarching title of a large array of carom billiards games generally played with two cue balls and a third, red object ball, on a cloth-covered, 5 foot × 10 foot, pocketless table that is divided by balklines on the cloth into marked regions called balk spaces. Such balk spaces define areas of the table surface in which a player may only score up to a threshold number of points while the object balls are within that region.

The balkline games developed to make the precursor game, straight rail, more difficult to play and less tedious for spectators to view in light of extraordinary skill developments which allowed top players to score a seemingly endless series of points with the balls barely moving in a confined area of the table playing area. Straight rail, unlike the balkline games, had no balk space restrictions, although one was later added. The object of the game is simple: one point, called a "count", is scored each time a player's cue ball makes contact with both object balls (the second cue ball and the third ball) on a single stroke. A win is achieved by reaching an agreed upon number of counts.

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