MDMD2: Transit of Venus

[Dave Monroe]

"As I have the honor of being nam'd your Second, upon
the propos'd Expedition to Sumatra, to observe the
Transit of Venus ..." (M&D, Ch. 2, p. 12)

>From Lisa Jardine, Ingenious Pursuits: Building the
Scientific Revolution (New York: Nan A. Talese, 1999),
Ch. 4, "Running Like Clockwork," pp. 133-76 ...

"... those who established land claims in places like
the new American colonies found that the
unsophisticated ways in which boundaries had been
decided quickly led to disputes between adjacent
owners.  [Edmond] Halley's [as in 'Comet'] interest in
magnetic variation and in the fact that magnetic
variation at any given point varied over time arose
out of disputes of this kind; territory originally
surveyed using a simple compass method had to be
resurveyed because of local alterations in magnetic
variation.
   "Following his own productive trip to St Helena,
Halley had repeatedly urged the Royal Society to take
advantage of a transit of Venus, which he knew would
occur in 1761, to organise simultaneous measurements
of the transit from points widely distanced on the
globe, and thence calculate the true distance of the
sun from the earth.  Almost twenty years after
Halley's death, two expeditions were duly dispatched
by the Royal Society, with funding from the King,
George II.  The fifth Astronomer Royal Nevil Maskelyne
returned to St Helena to observe a yet more infrequent
astronomical occurrence--a Transit of Venus (the
passage of the planet Venus across the disc of the
sun).  Meanwhile two enterprising amateur astronomers,
Charles Mason and Jeremiah Dixon, set off for
Bencoolen [Bengkulu] in Sumatra...." (p. 140)

This is merely the most concise account I had at hand.
 For fuller accounts, see, e.g., ...

Danson, Edward.  Drawing the Line: How Mason
   and Dixon Surveyed the Most Famous Border in
   America.  New York: John Wiley & Sons, 2001.

Howse, Derek.  Nevil Maskelyne: The Seaman's
   Astronomer. New York: Cambridge UP, 1989.

>From which I'll undoubtedly be posting as the occasion
arises (which should be shortly).  But in the
meantime, see also ...

http://www.dsellers.demon.co.uk/venus/ven_ch1.htm

... and keep clicking for further chapters.  This site
not only gives an excellent and well-illustrated
explication of said Transits, but also contains ...

Halley, Edmond.  "A New Method of Determining
   the Parallax of the Sun, or His Distance from
   the Earth."  Philosophical Transactions of the
   Royal Society, Vol. XXIX (1716): 45.

http://www.dsellers.demon.co.uk/venus/ven_ch8.htm

As well as a nifty bibliography ...

http://www.dsellers.demon.co.uk/venus/ven_ch7.htm

For the various expeditions to observe the Transits,
inc. Mason and Dixon's, see ...

http://www.dsellers.demon.co.uk/venus/ven_ch6.htm

The next such Transit will occur 8 June 2004 ...

http://www.dsellers.demon.co.uk/venus/ven_ch5.htm

And, while I'm at it, on that Expedition to Sumatra
...

http://www.gimonca.com/sejarah/mapsum2.html

http://www.lonelyplanet.com/mapshells/south_east_asia/sumatra/sumatra.htm

Bencoolen = Bengkulu ...




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