Dear Mac

> Here in Vermont a sundial is lucky to see the
> sun 15% of the hours in a year.

Hmmm, sounds worse than the U.K. :-(

> Heck, half of the time it's night!

Interestingly, this isn't true.  The number of days from
the March equinox to the September equinox is about 8 more
than the number of days from the September equinox to the
(following) March equinox.  This is much more than a
second-order effect!

In the northern hemisphere, therefore, we get more day
than night taking the year as a whole.  Down in the
southern hemisphere the reverse is true.

Only on the equator can you say `half the time it's
night' and even there you risk being told by a pedant
that night excludes the period of twilight.

Frank King
Cambridge, U.K.

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