Self-Adjusting Mystery Clock

The Puzzler

RAY: The hint I gave is that Mark said he didn't have one of these when he lived in Kansas.

TOM: Yeah, I said to myself, "In your house on the Cape you have a tide clock."

RAY: Right, and the tide doesn't care whether it's Daylight Savings Time or not. The tide is the tide is the tide.

TOM: You have that clock in your kitchen, but what is a tide clock?

RAY: It tells you when it's high tide.

TOM: How does it know?

RAY: It's an analog clock that has only one hand, the hour hand. It runs slower than a normal clock because the tides don't come at six-hour intervals. High tides are anywhere from 12 hours and two minutes apart to 12 hours and 50 minutes apart.

TOM: And you certainly don't have to change it when they change all the other clocks.


[ Car Talk Puzzler ]

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