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Subject: Re: Is Sextant an Optical Device?
From: Rodney Myrvaagnes (rodneym@XXX.XXX)
Date: Fri Oct 04 2002 - 15:16:34 EDT
The horizon, mountain peak, mast, or whatever else are only connected
to the sextant by light, i.e. optically. The telescope is not part of
the essential nature of the sextant, nor is it what makes it optical.
It does indeed measure angles, but angles between optical images of
distant objects.
If you remove the mirrors from a sextant, it is no longer a sextant. A
car is still a car without rear-view mirrors, or with a dozen.
On Fri, 4 Oct 2002 10:31:41 -0700, David Weilacher wrote:
>Well, no. A horizon isn't a light source.
>
>If you use it to determine distance off from a mountian peak or tall tower,
>those aren't light sources. I've used mine in a regatta to determine if I was
>gaining or losing on a mast in front of me, not light sources.
>
>
>
>Unless you mean that if you use your eye, it must be optical.
>
>
>
>I'm pretty sure that what it does is measure angles. Angles that can be
>measured with or without the telescope.
>
>
Rodney Myrvaagnes J36 Gjo/a
"If Brecht had directed 'Waiting for Godot,' he would have hung a large sign at the back of the stage reading 'He's not going to come, you know. ' " -- Terry Eagleton
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