Three guys, one Irish, one English, and one Scottish, are out walking along the beach together one day. They come across a lantern and a Genie pops out of it. "I will give you each one wish, that's three wishes in total", says the Genie.
The Scottish guy says, "I am a fisherman, my Dad's a fisherman, his Dad was a fisherman and my son will be one too. I want all the oceans full of fish for all eternity." So, with a blink of the Genie's eye FOOM! the oceans were teaming with fish. The Englishman was amazed, so he said, "I want a wall around England, protecting her, so that no one will get in for all eternity."
Again, with a blink of the Genie's eye POOF! there was a huge wall around England.
The Irishman asks, "I'm very curious. Please tell me more about this wall." The Genie explains, "well, it's about 150 feet high, 50 feet thick, protecting England so that nothing can get in or out."
The Irishman says, "Fill it up with water."