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xkcd #2935: Ocean Loop
(imgs.xkcd.com)
Alt text:
I can't believe they wouldn't even let me hold a vote among the passengers about whether to try the loop.
I don't think he's done one with ocean liners but he did one with trains.
I was actually more curious about the water itself and forgot we were even talking about a boat lol. Could you force that much through an open loop without it sloshing back inward?