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From: George Huxtable (no email)
Date: Sat Dec 10 2005 - 04:31:10 EST
> George H, you wrote:
> "Yes, a "makeshift Royal Observatory", in Frank's words, could have been
> useful for Baffin's mapping, but the time wasn't ripe for it then."
>
> Yes, alas that's true. I was thinking more in terms of a "what if" here,
> George. IF European astronomy had devoted more effort to precision naked
> eye
> observatories, then the idea of observing simultaneous with exploration
> voyages
> might have seemed more obvious. It would have worked much better than
> comparing with the relatively poor ephemeris calculations available at
> that date.
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Comment from George-
That's taking "what if" rather far.
Why were ephemeris calculations so poor then?
Frank mentions "precision naked-eye observatories". But that in itself is
somewhat contradictory. Precision observation was not possible until
telescopic sights were evolved, and the telescope wasn't invented yet, in
Baffin's time, around 1612, late in the 17th century..
But a bigger problem, even for naked-eye observation, was the difficulty of
dividing an arc into a precise angular scale. Arcs divided so as to allow
averaged readings to within a minute didn't appear until 150 years later.
Another difficulty that affected observatories was the lack of proper
clocks, until Huyghens invented pendulum clocks.
And precise calculation was impossible until the laws controlling the
planet's motions were understood, which had to wait for Newton.
So Frank is telescoping more than a century of scientific and technical
achievement into nothing, with that "what if"!
George.
contact George Huxtable at
or at +44 1865 820222 (from UK, 01865 820222)
or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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