19 Dec
2008
19 Dec
'08
7:56 p.m.
Ethan Dicks wrote:
There were moon dialks, and things called Nocturnals which told the time
by sighting stars. IIRC, though, you need to know the date to use either
of those (unlike a normal sundail, where you need the date only for the
equation of time correction, and can get the time to within half an hour
without it.
So many ways to tell time in the modern era.
This is a huge change
from a few centuries ago, when a marked stick was close enough.
Nope ... Looks out side, it is dark but is it after midight yet? Hard to tell with this candle what notch my sundial stick is at.
While you don't get time as accurate as moden clocks
A Heliochronometer will give you the (local apparent) time to within a few
seconds, which is probably as good as most mechanical clocks.
sundial and moondials are still interesting time
telling devices.
Inded they are. The problem with many of the books on making sundials is
that they were written before the avaialbilitiy of computing devices (even
mecvhanical calculators, let alone electronic calculators or personal
computers0, so they give geometical constructions for the hour lines. I'd
perefe to know how they were calculated, then calculate the angles I need
using something electornic and then mark those angles on the dial plate.
Timekeeping devices are (and always have been) an interest of mine. All
types of timekeeping devices -- sundials, mechanical clocks, electic
clocks, electronic clocks, and so on.
-tony