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From: Alexandre Eremenko (no email)
Date: Tue May 24 2005 - 13:59:05 EDT
George,
On Tue, 24 May 2005, George Huxtable wrote:
> There's a superb Troughton circle, on the lines I have described, and
> mounted adjustably on a pillar, at the History of Science museum in Oxford.
> I think such pillar-sextants must have been intended for precise
> measurement of lunar distance by a land-based observer.
I forgot to mention that the circle I saw in Dresden
was also mounted on a pillar.
(I was not permitted to handle the instrument:-(
of course:-)
but my impression was that it should be too heavy for
observations "from hand".
However it had the usual U-shaped handle of most reflecting circles.
(I recall, the diameter of the circle was 1.5 ft,
and it was entirely made of solid bronze or brass).
I recently had an opportunity to try the brass sextants
of Fred (CP and a small Husun/Mate). I found them extremelly heavy:-)
My hand was tired.
And Fred said he liked my aluminium SNO-T, because of its lightness.
A
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