"Edgar" wrote in message
...

"Capt. JG" wrote in message
news:J8ednTRMl5onF5bVnZ2dnUVZ_gqdnZ2d@bayareasolut ions...
Can you navigate (lat and long) at night with a sextant and a compass,
but without a nautical almanac, sight reduction tables, the time of day,
and without knowing the names of the stars? The sextant has an error, but
you don't know what it is, just that it's off. You can keep your modern
watch, but you just replaced the battery and the time is wrong.

I say that you cannot.
Firstly because at night you probably cannot see exactly where the horizon
is.Even if you got an aeronautical sextant with a bubble level they are
very hard to read on a boat if it is at all rough
Secondly because you cannot derive longitude without an accurate watch.


Does someone own a sextant? What model? I'm thinking about picking one
up.

You do not say what you want it for. For use aboard or just as a talking
point at home?.
You can get various plastic sextants that do a good enough job for use on
a small boat where pinpoint accuracy is hard to achieve.
But a proper sextant is a thing of beauty and mine is a Kelvin Hughes
dating from 1959 which is in pristine condition in its box with all
accessories. I take the odd reading with it from time to time to keep my
hand in in case both my chartplotter and my DR on paper charts fail me.
Mine is a micrometer type but retains the silver engraved scale which is
somewhat overkill for a micrometer since you only need to use the scale to
read whole degrees. But it is very nice to look at an inlaid silver scale.
Vernier sextants are older and are collectable antiques now and
regrettably mostly end up in museums or hanging on someone's wall.
There are a lot of authentic looking but purely decorative ones about
which are not suitable for navigation. Make sure yours comes with an
authentic test certificate.



I never said it would necessarily be a boat that was in rough conditions.
That is always difficult.

The sextant would be a backup, a talking point, and something to mess with.


--
"j" ganz @@
www.sailnow.com