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Re: Balloon Sextants
From: Geoffrey Kolbe
Date: 2016 Mar 29, 07:14 +0100
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From: Geoffrey Kolbe
Date: 2016 Mar 29, 07:14 +0100
On 28 March 2016 at 17:28, John D. Howard <NoReply_Howard@fer3.com> wrote:
The eyepiece is in the horsontian axis.
....?
Interesting term. I have never seen it, and Google does not seem to be able to turn it up either.
I have seen PiBal theodolites (for that is what they are) referred to as "broken axis" theodolites, or broken theodolites and as such bare a resemblance to the Wild T4 theodolite, with which angles to a tenth of a second of arc could be achieved. Unfortunately, almost all PiBal theodolites will only read to tenths of a degree and so are pretty limited when it comes to celestial work.
This is a nice website about PiBal theodolites. http://web.csulb.edu/~mbrenner/balloon.htm
Geoffrey Kolbe
Dr Geoffrey Kolbe, Riccarton Farm, Newcastleton, Scotland, TD9 0SN
Tel: 013873 76715
Mob: 0773 8069 663
