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Inventory no. 47674 - Former Display Label

12 Late Gothic ASTROLABE c.1450

Not dated; inscribed, in the mater, 'Jeh Charla'. Brass. Diam.: 282 mm.

Probably had one loose plate, now missing; the mater is engraved as a plate for latitude 40°, and all the
90 almucantars are drawn. The rete, for 37 stars, is weighted by lead placed in the lower semi-quatrefoil,
not so much, perhaps, to cause the rete to return to a central position when the astrolabe is suspended, as
to weight the whole instrument to facilitate observations. However, the ecliptic circle of this astrolabe is
wrongly divided, rendering it useless, and the authenticity of the instrument is not above suspicion. The
back is engraved with an unequal-hour diagram, and a shadow-square, within a zodiac/calendar scale (0°
Aries = 11 March, eccentric type). The rule is probably a replacement. What appear to be dominical
letters are marked at the centre of the alidade and at the beginning of each monthly division on the zodiac/
calendar scale.

[IC 163] Lewis Evans Collection

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