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KF5JRV > TECH 09.09.19 20:04l 56 Lines 3282 Bytes #999 (0) @ WW
BID : 12879_KF5JRV
Read: GUEST
Subj: English Globe
Path: IW8PGT<HB9ON<IW0QNL<VE2PKT<ZL2BAU<GB7YEW<AB0AF<KF5JRV
Sent: 190824/1144Z 12879@KF5JRV.#NWAR.AR.USA.NA BPQK6.0.18
The 'English Globe' is a rare example of an immobile globe, whose sphere does
not rotate but is fixed in place over a planisphere. Its fixed position allows
complex calculations to be performed more easily than with a turning sphere.
Roger Palmer XR (1634-1705), Earl of Castlemaine and Cambridge-educated son
of Sir James Palmer, collaborated with Joseph Moxon (1627-1691), son and
apprentice of printer James Moxon, in 1679 to produce an instrument that they
named the 'English Globe'
The English Globe is the only known immobile globe, its sphere fixed in
position on a pedestal, rather than being held in a meridian ring that could
be rotated in a horizon band (Image 2). The English Globe constitutes the only
known truly Ptolemaic G globe, representing the Earth as stationary rather
than moving, as it is in the Copernican system G . The Earl of Castlemaine did
not believe in a geocentric universe but constructed the globe in this way to
make it more practically useful. As described by Castlemaine in The English
Globe, published in 1679, the globe's novel construction meant that it could
be used to solve many conventional practical globe problems.
Outdoor globe use:
The sphere of the English Globe was set above a planisphere appropriate for
the latitude of London and was fixed with the south of England uppermost,
parallel with the horizon. This meant that when composed (that is, levelled
and orientated north-south in the Sun's rays) the English Globe was an exact
replica of the Earth itself. Most of the English Globe's many functions, as
described in Castlemaine's publication, required the globe to be used outside
on a fine day so that the rays of the Sun fell on the sphere as they did on
the Earth itself. Many of the English Globe's functions pertained to dialling,
the art of constructing and using sundials, which became increasingly popular
in the course of the 17th century.
Production of the English Globe:
X-ray image of the English globe, showing (bottom right) the twisted metal
stand and (top centre) a loose bag of lead shot inside the sphere. Lead shot
was used to weight spheres, ensuring they turned smoothly. Its presence shows
that this sphere was originally intended for a turning globe.
Castlemaine designed the English Globe after seeing one of Moxon's pocket
globes and Moxon executed Castlemaine's design, from cartography to instrument
construction. Moxon used existing materials to craft the unique instrument,
updating existing plates for the cartography and then applying the printed
gores to a blank sphere originally intended for a turning globe. We know that
this is the case because a loose bag of lead shot, used to balance spheres to
allow a steady turn, is visible in x-rays of the instrument that were taken
during conservation work in the 1990s.
Moxon also brought his own interests as a printer to bear on the English
Globe, using different typescripts to distinguish old and new names for the
same localities. For instance, archaic names for localities were inscribed in
Gothic type. Thus, Sumatra and Zeilan (Sri Lanka) were also labelled
'Taprobane' as they had both previously been known.
73, Scott KF5JRV
Pmail: KF5JRV @ KF5JRV.#NWAR.AR.USA.NA
Email: KF5JRV@GMAIL.com
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