13. In playing a shot, if the cue leaves the ball and touches it again, the stroke is foul.
14. If the striker, through stretching forward or otherwise, has not at least one foot on the floor while striking, the shot is foul, and no points can be reckoned.
15. If, when the player’s ball is in hand, he does not cause it to pass outside the string before touching any of the object-balls or cushion (except in the case mentioned in the following rule), the stroke is foul, and his opponent may choose whether he will play with the balls as they are, have them replaced in their original positions, or cause the stroke to be played over; or, should the player make a losing hazard under such circumstances, the penalty may be enforced.
16. Playing at a ball whose base or point of contact with the table is outside the “string,” is considered playing out of the “string;” and the stroke is a fair one, even though the side which the cue-ball strikes is hanging over, and therefore within the “string.”
17. Playing directly at a ball that is considered in the “string” is foul, even though the cue-ball should pass wholly beyond the “string” line before coming in contact.
18. Giving a miss inside the “string,” when the player is in hand, is foul. But he may, for safety, cause his ball to go out of the “string” and return.
19. If a player alters the stroke he is about to make, at the suggestion of any party in the room,—even if it be at the suggestion of his partner in a double match,—the altered stroke is foul.
20. Placing marks of any kind whatever, either upon the cushions or table, is foul; and a player, while engaged in a game, has no right to practise a particular stroke on another table.
ON CASES WHERE THE BALLS ARE IN CONTACT.
[At the request of a majority of the leading players, amateur and professional, the rule observed since 1858, under which no count could be effected unless the striker first played upon some ball other than that with which his own was in contact, has been amended as below. The new rule came into effect January 1, 1867.]