NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Observations with pocket sextant in the Baltic CROSS POST
From: Alexandre Eremenko
Date: 2006 Jul 5, 02:02 -0500
Dear Red,
> I could see them measuring by several ways,
In Freiberg factory I saw the measuring device,
and the procedure of measuring.
The sextant clamped horizontally on a table.
The device sends two rays, one into each mirror,
under prescribed angle 10 degrees (then 20 degrees etc).
The operator measures this angle as we measure angles with
the sextant: he looks through the telescope, moves the arm, and then
rotates the drum, until the two rays coincide in his field of view.
Then he records the drum reading.
> Undoubtedbly, but I have corresponded with them
> in the past and the brief
> impression I got was of folks who take price in their craftsmanship
The guy who measured my sextant did not speak English
and I do not speak German:-(
We had a translator, a sales agent of the factory,
but the translator was not familiar with terminology.
> Or perhaps the folks at Robt.White in Boston
This is a good idea. I know Robert White.
Probably I will have this sextant tested by him when I come back
to the US.
> I'm suggesting that you can take a hole puncher
> from a stationery store, punch out a small circle of the tint material,
I will experiment when I come home.
> "The glass of the art horizon can be blackened with a candle."
> Candle soot...well, that's traditional but do you really want to put a flame or
> soot near your sextant??
No! I am talking of the Davis art horizon (of usual construction),
not the sort attached to the sextant.
A Davis art horizon is a plastic container with water,
covered by a simple piece of glass.
It is this glass that I plan to blacken with a candle.
It is not a part of a sextant:-)
To be sure, Davis horizon comes with 4 glass covers, 2 transparent
and two colored. But the colored glasses are not dark enough
to look at the Sun through them. (Actually I do not understand what is the
purpose of these two colored glasses then).
> If you've got a high school with a metal shop
> someplace in the area,
I have my university machine shop. Unfortunately they will
not do something just for money. They need an official order,
to be payed from my research account or research grant.
And my official research area
has nothing to do with sextants of Cel Nav:-)
That's why I would rather try the machine shop on the web
that you suggested in the beginning.
Alex.
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To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
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From: Alexandre Eremenko
Date: 2006 Jul 5, 02:02 -0500
Dear Red,
> I could see them measuring by several ways,
In Freiberg factory I saw the measuring device,
and the procedure of measuring.
The sextant clamped horizontally on a table.
The device sends two rays, one into each mirror,
under prescribed angle 10 degrees (then 20 degrees etc).
The operator measures this angle as we measure angles with
the sextant: he looks through the telescope, moves the arm, and then
rotates the drum, until the two rays coincide in his field of view.
Then he records the drum reading.
> Undoubtedbly, but I have corresponded with them
> in the past and the brief
> impression I got was of folks who take price in their craftsmanship
The guy who measured my sextant did not speak English
and I do not speak German:-(
We had a translator, a sales agent of the factory,
but the translator was not familiar with terminology.
> Or perhaps the folks at Robt.White in Boston
This is a good idea. I know Robert White.
Probably I will have this sextant tested by him when I come back
to the US.
> I'm suggesting that you can take a hole puncher
> from a stationery store, punch out a small circle of the tint material,
I will experiment when I come home.
> "The glass of the art horizon can be blackened with a candle."
> Candle soot...well, that's traditional but do you really want to put a flame or
> soot near your sextant??
No! I am talking of the Davis art horizon (of usual construction),
not the sort attached to the sextant.
A Davis art horizon is a plastic container with water,
covered by a simple piece of glass.
It is this glass that I plan to blacken with a candle.
It is not a part of a sextant:-)
To be sure, Davis horizon comes with 4 glass covers, 2 transparent
and two colored. But the colored glasses are not dark enough
to look at the Sun through them. (Actually I do not understand what is the
purpose of these two colored glasses then).
> If you've got a high school with a metal shop
> someplace in the area,
I have my university machine shop. Unfortunately they will
not do something just for money. They need an official order,
to be payed from my research account or research grant.
And my official research area
has nothing to do with sextants of Cel Nav:-)
That's why I would rather try the machine shop on the web
that you suggested in the beginning.
Alex.
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
