Oh just had one more thought or two really. If the exotic matter is causing a balloon blow hole effect around the island it could also explain how the island is "moved". Two options:

1. When Ben cranks the wheel round to move the Island maybe he's not moving the Island but is instead shifting the exotic matter around the Island to move the position of the "blow hole". What this would do would be to let the Island stay exactly where it is inside its spacial area and simply move the "blow hole" around the Island with a new position in the pacific (relatively near to the original position) and a brand new compass bearing in and out of the Island's spacial area. The new position of the "blow hole" would still remain within a few square miles of its original position because the Island hasn't actually moved but would still be small enough to be very hard to find PLUS would require a whole new set of compass points to enter and exit.

or

2. Not sure if its even possible but by moving the wheel inside the Island maybe Ben squeezed the points in space at the enter/exit point of curved space together and pulled the Island from its original point in space altogether. This would cease to be a balloon effect and instead would mirror the characteristics of a bubble breaking away on its own. The bubble would be completely self contained with the Island at its centre. If this were so I would imagine that what would need to happen is the Island bubble would reintegrate itself back into an ocean at a new position with the original characteristics of the balloon effect (also with its original compass points just at an entirely new spot in one of the worlds oceans). Should this be the case the inhabitants of the Island can either control the Island and keep it in its bubble for as long as they want and bring it back to any location they want or the bubble would instantly transfer from point one to point two and the inhabitants of the Island would shift positions without noticing any change and without any control over final position.

Either of these explanations would also explain the Island disappearing and the water rippling as the original space reasserts itself without the Island.

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