It will be noticed the line k through the cue meets the spot h on the ball which is the point of aim, and this should be the case in every description of stroke. Only a part of the surface of the leather impinges upon the ball in this stroke, and the quantity of surface is governed by the strength used, for the stronger the blow the greater the indentation of the ball in the leather. The effect of delivering the cue-ball on the object-ball right or left of full will become apparent to the student early in his practice.
The cue may be delivered still farther above the centre—a ⅝ delivery, which imparts excessive rotation, and which is as far above as the leather will hold on the ball surface. The “follow” can also be executed with the cue delivered as far as one-fourth below centre, but the latter delivery should be with a “slow” strength of stroke, that the ball may rotate naturally; if it be full upon the object-ball and with strength exceeding “medium,” the cue-ball will stop, or will perform a right angle if played a fraction off the centre, as shown in Plate IV., Balls 1 and 6.
The Draw-Stroke.
Turn the diagram so the letter B may come beneath it and the draw-shot is illustrated.
The delivery as shown is one-half below centre, with the central line k through cue meeting the point of contact, h, on ball, and imparting to it three distinct forces, that of impulsion, rotation, and retrograde, the latter causing the cue-ball to rotate in direction of the arrow b; the strength of this force is such as to counteract the natural tendency of the impulsion, prevent the forward rotation, and cause the ball thereby to slide over the cloth without the rolling motion. This stroke holds the ball (thus preventing for the instant its natural rotation) in a position corresponding with the line e to i, the moment the impelling force is communicated to the object-ball, which is at the instant of contact, the retrograde power acts with all its remaining strength, and it returns in the direction of the player. The distance between the balls must regulate the strength of the stroke, but greater distance between cue- and object-ball requires greater force, that the cue-ball may retain its retrograde tendency which prevents its being displaced by friction in sliding over the cloth, which inertia in the cue-ball acts in the direction of dotted line i to j. A delivery ½ below, with the object-ball the length of the table away, will act as a “slowed” ball only. The quick, sudden delivery movement of the cue made with the aid of the wrist is what imparts the retrograde or “draw” tendency to the ball; there should be no spasmodic motion, but a free and horizontal blow direct at the calculated spot on the surface of the cue-ball, permitting the cue to pass naturally beyond where the cue-ball has rested, as the grip of the hand upon the cue will stop the latter when the limit of its swing is reached, except where cue- and object-balls are near together; in the latter case, that a foul may be avoided, a “twist” or “English” is imparted to the cue-ball, which carries the cue naturally off the side of the cue-ball.
Do not withdraw the cue; it is an awkward habit many persons have acquired. The limit of the swing of the cue is governed by the strength of the stroke. Full instructions in regard to the cue and its delivery have already been given.
The “English” or “Twist”-Stroke.
Bringing C beneath the diagram, we have the “English” stroke, with the cue delivered at ½ right of centre, which imparts to the cue-ball a perpendicular axis. A variation to the slightest degree in twist makes a difference in the direction of the cue-ball, which can only be appreciated by those who have studied it carefully.
A player, when instructed to deliver a ⅛ cue-ball, for instance, will disregard the direction and deliver a ¼ or even a ½ ball, apparently unconscious or careless of the value of the change. When it is understood that a cue-ball may be made to carom upon a ball placed anywhere upon the bed of the table by the application of the proper degree of twist, then the player will recognize the necessity or advisability of so fixing the various degrees in his mind as to have them always ready for use. A twist secures, of course, a false angle, and is used generally when the natural angle will not accomplish the result desired, and again, often is employed to control the object-ball.
The velocity of the cue-ball in the twist-stroke is governed by the divergence from the centre at which delivery of cue is made. There is a method in employing twist which is effective, that of combining it with the division of the object- and cue-balls, giving an exact line of aim to be had in no other way. When the twist is applied to that side of the cue-ball coming in contact with the object-ball, the aim will be more positive, as the cue covers the exact line of aim through the two balls.