Article 14 says, in part

If the jack, having been hit, is stopped or deviated by a player located in-bounds of the game terrain, his opponent has the choice of:

- (a) leaving the jack in its new position;
- (b) putting it back in its original position;
- (c) placing it anywhere on the extension of a line going from its original position to the place that it is found, up to a maximum distance of 20 meters from the circle (15 meters for the younger players) and such that it is visible.
Paragraphs b) and c) cannot be applied except if the position of the jack had been marked previously. If that was not the case, the jack remains where it is.

14c just cries out for a diagram. So I drew one.

- Point A is the original position of the jack.
- Point B is the new position of the jack.
- Note that we know exactly where point A is, because in order for clause (c) to apply, point A must have been marked. This requirement makes perfect sense — you can’t use a technique that involves drawing a line from point A to point B if you don’t know where point A is.
- The line segment between B and the arrowhead is the “extension” of the line from A to B. The opponent may (if he wishes) relocate the jack to any position along this line segment.

The sort of common-sense philosophy behind 14c is, I think, this.

The arrow drawn from A through B represents the direction in which the jack was travelling before it was improperly interfered with. If the jack had NOT been interfered with, it would have continued to travel in that direction. Eventually it would have come to rest somewhere along that path. So the opponent (the injured party, as it were) has the right (if he wishes) to place the jack at any location along that path where he thinks the jack would eventually have come to rest. In actual practice, of course, this means that the opponent has the right to place the jack anywhere he wishes, assuming he places it somewhere on the line between B and the arrow-head (20 meters from the circle).

14c stipulates that the opponent may not place the jack more than 20 meters from the circle (which would kill it), so on an open terrain, the jack is unlikely to die, regardless of what choice the opponent makes. But in a game played on a marked terrain, there are some situations that can result in a dead jack. If point B is out-of-bounds, and the opponent chooses to leave the jack at point B, then the jack is dead. Or the opponent may choose to invoke 14c and move the jack until it is 20 meters from the circle. On a marked terrain, this will almost certainly place the jack out-of-bounds, effectively killing it.

And of course, if the original position of the jack was NOT marked, then the only option is to leave the jack in its new position (point B). If point B is out-of-bounds, the jack is dead.