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KF5JRV > TECH     05.09.16 17:32l 66 Lines 3770 Bytes #999 (0) @ WW
BID : 1484_KF5JRV
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Subj: Pocket-sized Globes
Path: IW8PGT<CX2SA<N0KFQ<KF5JRV
Sent: 160905/1515Z 1484@KF5JRV.#NWAR.AR.USA.NA BPQ1.4.65

Pocket-sized globes

Pocket-sized globes, measuring around 3 inches in diameter, had several 
functions including acting as status symbols for gentlemen and educational 
tools for children. Although the popularity of pocket globes peaked in the 
first half of the 18th century, makers continued to produce the items into the 
19th century.

Joseph Moxon brought pocket globes to England between 1659 and 1670. Pocket 
globes consist of a terrestrial sphere of around 7.5cm in diameter inside an 
outer case, which often bears celestial cartography. 

Much of what we know about the uses of globes comes from instruction manuals. 
However, few, if any, pocket globes had accompanying booklets, so it is 
difficult for us to know who used these objects and for what purposes. It is 
unlikely that pocket globes served precise practical ends; their size makes 
accurate calculations impossible, and they tend to lack the rings and dials 
required for the most common manipulations. Additionally, makers continued to 
use pictorial constellation figures on pocket globes, even after the images 
fell out of use on larger globes as they were considered 'unscientific'.

Pocket globes could have served as status symbols for wealthy gentlemen. 
Alternatively, the small globes could have been used in children's education, 
especially since they were made of cheap materials such as papier mâché. 
Authors suggested that children suspended a 3-inch globe near a candle, 
representing the Sun, to demonstrate the passing of day into night. Some 
pocket globes have a hole drilled through their spindle, which could have been 
threaded with a cord for hanging. The printing firm Darton and Co. specialised 
in children's literature. This supports the idea that children were a 
prominent audience for pocket globes.

Looking out on the heavens

The celestial sphere is an imaginary surface surrounding the Earth onto which 
stars are mapped. The surface of a celestial globe represents the celestial 
sphere. Standard globes have a convex surface, and stars are marked as if the 
observer is looking in on the celestial sphere from the outside. This is 
called an external projection. However, pocket globe cases offered a concave 
surface, so that the heavens were mapped in the way that an observer looking 
out from Earth would see them. This is called a geocentric projection. In 
1731, Richard Cushee became the first maker to use geocentric projections on 
the concave surface of a pocket globe case for a in 1731. Darton used Cushee's 
method for his pocket globes and showed the heavens as they appeared from 
Earth. This gave users the impression of being inside a larger celestial 
globe, or the celestial sphere itself.

Patriotic cartography

Although Darton's pocket globe was probably aimed at children, it dealt with 
some mature themes. Darton depicted the track of George Anson's blighted 
circumnavigation of 1740-1744, a voyage in which around 90 percent of the men 
lost their lives. This voyage recorded an important episode in English 
imperial history. Anson's journey was celebrated as a significant success 
among multiple failures in the war with the Spanish in the Caribbean and on 
the Pacific coast of South America. By showing this route, along with that of 
Captain James Cook's mission to claim the east coast of Australia, Darton 
encouraged children to remember important events in their country's maritime 
history. England is also celebrated on Darton's globe as the home of the 
meridian of zero longitude. Darton shows the Prime Meridian passing through 
the south east of England, even though the meridian was not officially settled 
until the International Meridian Conference of 1884.


73, Scott kf5jrv
KF5JRV @ KF5JRV.#NWAR.AR.USA.NA


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