| Date |
1221/2 (A.H. 618) |
| Maker |
Muḥammad ibn Abī
Bakr |
| Place |
Iṣfahān |
| Material |
Brass |
| Inventory no. |
48213 |
| Acquisition |
Presented by Lewis Evans in
1924 |
The rete is of the indicator-line (quatrefoil) type.
There is a single rotation knob and two sighting vanes on the
front of this rete. A single quatrefoil decorates the center
of the ecliptic..There are three zoomorphic star pointers on
this rete. The first is the typical bird (falcon ?) that
indicate the star Vega. The second is another bird, this time
depicted as if in a dive, which points to the star al-Tayir.
The third is a horse that points to the star Mankib.The
zodiac on the rete is labelled: الحمل , الثور , الجوزا ,
السرطان , الاسد , السنبله , الميزان , العقرب , القوس , الجدي
, الدلو , الحوت
Stars
There are 0 stars on the rete marked with
dagger pointers. Unless otherwise indicated the star name,
mediation and declination are as marked/measured on the
rete.
Click on the star name or modern star name to search for
other astrolabes with the same star.
Star name
(on instrument) |
Modern star
(if known) |
Mediation |
Declination |
Pointer |
Pin & Wedge
The rete is attached using a pin
& wedge. The pin is in fact an axle that rotates with the
rete to drive the gears. These, in turn, cause the phase of
the moon diagram and the solar-lunar diagram to change
accordingly. It looks to be a replacement..
