I once read something to the effect that the apparent diameter of the sun's disk is just about the same as the light curvature due atmospheric refraction (or is it gravity-bending? that sounds unlikely) when it reaches you at a tangent; with the net effect being that when the sun's disk just touches the horizon it's "really" entirely below it. And it's by this means we know that, like the light in your refrigerator when you close the door, the sun doesn't go out when it falls below the world's edge and everything you've been told otherwise is a damned lie.

[Dan] Take it up with CdM or Breadmaster. But before you do, consider: wouldn't your "width" theory mean that you'd be forever smashing the fridge light bulb in the door? Something about that doesn't ring true.

Can't help I'm afraid but do have a very Happy Christmas wherever you are. _, who is now 3, is already as manic as can be. Not sure how to burn off his energy...

(Dan) True. If you see the sun on the horizon it is geometrically just below it. It adds a few minutes to daylight at each end. It's refraction (strictly, differential refraction) not gravity-bending which would need a mind-bogglingly dense earth. On Venus the refraction is so large the horizon is above horizontal and it looks as if you're living in a bowl. A hot one, 460°C. No oxygen. Occasional showers of sulphuric acid.
(rab) See MCIOS, FUQs.

(Dan, Stevie) Nor the light in the boot of your car.

[rab] Isn't there a version of those ball-throwing arm extensions for dogs that you can get for kids? Alternatively, send him off to an aunt and uncle for the afternoon.
Merry Xmas, all.

Unfortunately the only aunt-uncle combo is based in NZ, so it'd be more than an afternoon...

AFAIR playgrounds are good. Choose one with a convenient bench from which to watch. Or join in if you're not self conscious. Something requiring concentration, like Lego can be surprisingly tiring. The best thing is to forget your boring adult lifestyle and simply play all day.

[penelope] I looked everywhere but found no trace of these canine-oriented ball-atlatls you steered rab toward. How would the dog wield such a thing anyway, absent opposable thumbs? What rab needs is a keen, ankle-nipping bull terrier. Half an hour of being chased around the park by the dog will tire the child out nicely, and give him or her a healthy respect for vicious dogs.

Of course, if the dog is too keen there is a chance the plan will backfire as the dog chases you instead of the child.

To help prevent this possibility, soak the child's shoes in bacon grease before releasing the terrier.

Also, to minimize the risk of vigorous shoe-licking instead of ankle-nipping, thrash the dog soundly for five minutes a day with a side of bacon.