Double-sided planispheric astrolabe

Double-sided planispheric astrolabe

Copper alloy with engraved decoration. The kursi (throne) and limb, cast in one piece with a cleat to accommodate the legs of the plates, house nine discs comprising the mater (mother), six double-sided tympanums, and two spiders. Four hooks fixed to each face of the limb hold the discs on either side of the astrolabe. Engraved alidade and horse-shaped pin. H. with suspension chain: 29 cm D. 13 cm Full-size copy of a two-sided Indo-Persian astrolabe for the northern and southern hemispheres from the original formerly in the collections of the Time Museum, Rockford, Illinois, now in the Adler Planetarium, Chicago. Very well executed, this brass astrolabe is the same size (D. 127mm) as the original, but with a few slight differences (incorrect spider projections, awkward divisions, weak calligraphy). Astrolabes with projections for both hemispheres are extremely rare. The one in the Time Museum is the most complete known. For a detailed description, see A. J. Turner, The Time Museum: Catalogue of the Collections, I. 1 Astrolabes and astrolabe related instruments, Rockford 1985, pp. 74-83. Provenance : Former collection of Mr D. M. (1942-2017) A double-sided planispherical astrolabe We thank Mr. Anthony TURNER for the description of this lot.