Peter,
Indeed, there are two telescopes used to sight stellar objects (of known
sidereal hour angle i.e., RA) and an arrangement of arms that allows the
objects local hour angle to be read via the dial plate. This was to allow the
dial to function at night and appears to me to have been more trouble than it
was worth. Accuracy was claimed within a minute. It hasn't been reprinted as
far as I know.
The title came to my attention when it was mentioned (check your past
e-mails, I'm about with my laptop, sorry) as the first English printing of
Flamsteed's EoT values, Molyneaux includes it as an appendix. Flamsteed's
values were of much greater accuracy than anyone else at the time.
Flamsteed's analytic work on the equation of center may have helped in this
regard, though I'm not certain by any means. At any rate, Flamsteed was a
marvelously gifted mathematician and astronomer.
-Luke
> Luke or other dialists,
> I am quite intrigued by the title of this old book:
> > _Sciothericum Telescopicum or A New Contrivance of Adapting a
> >Telescope to an Horizontal Dial_ by William Molyneaux, 1686
>
> Does Molyneaux describe a sundial that is augmented by an optical system?
> Can you summarize this contraption? Any claims for accuracy?
> Finally, was the title reprinted in modern times?
> thanks,
> Peter
>
> _______________________________________
> Peter Abrahams [EMAIL PROTECTED]
