1.—Cue ball struck midway between centre and top and aim taken at edge of object ball when balls are near together. Result: Natural angle instead of finer stroke otherwise necessitated.
2.—Cue ball struck centrally and aim taken at edge of object ball when balls are near together. Result: Slight stun deflection beyond the natural angle.
3.—Cue ball struck centrally and aim taken rather fuller than half-ball when balls are near together, with rather heavier handling. Result: Increased stun deflection.
4.—Cue ball struck slightly below centre and aim taken almost full, when balls are near together, with same handling as No. 3. Result: Object ball driven almost straight and cue ball deflected slightly (a spot and top-of-table stroke).
5.—Cue ball struck midway between centre and bottom and aimed at edge of object ball when balls are near together. Result: Right-angled screw.
6.—Same stroke aimed half-an-inch fine. Result: Fine
7.—Same stroke aimed half-an-inch fine. Result: Screw taking direction midway between right angle and half-ball.
8.—Same stroke aimed half-an-inch thick. Result: half screw-back taking direction midway between right angle and straight draw-back.
9.—Same stroke aimed dead full. Result: Straight draw-back.
Note: Force is only needed in screw strokes when the balls are far apart or the cue ball has cushions to encounter and a desired position to reach after contact. A prime secret in successful billiard play is to make all strokes as gently as possible and work up to greater force only where absolutely needed, instead of vice-versa. In screws the great secret is drawing lightly-held cue well back and sending it right through the ball.