Astrolabe Catalogue

 

Small image of astrolabe back with rules or alidades removed. Click to enlarge.
Date 1641 (A.H. 1051)
Maker Ibrāhīm ibn Sharaf ad-Dīn Ḥusain
Place Persia
Material Brass
Inventory no. 43148
Acquisition Presented by Lewis Evans in 1924

Back



The back contains 10 scales of the following types:
Type
(click to view scale details)
Range & Units Numbered Geometry Location
Altitude 0 - 90, Degrees Every 5 degrees Circular, concentric Upper right quadrant of outer circular on back of instrument.
Altitude 0 - 90, Degrees Every 5 degrees Circular, concentric Upper left quadrant of outer circular on back of instrument.
Declination Gemini/Cancer - Sagittarius/Capricorn, Zodiacal sign Not numbered  Arc Upper right quadrant (inside circular scales)
Sine/Cosine 1/60 of quadrant radius Not numbered  Angle Upper left quadrant (inside circular scales)
Cotangent 0 - 36, Feet Every 6 feet Circular, concentric Lower left quadrant of outer circular on back of instrument.
Cotangent 0 - 42, Fingers Every 6 fingers Circular, concentric Lower right quadrant of outer circular on back of instrument.
Shadow square 0 - 7, Feet Every 1 feet Box Left hand vertical 'face' of the shadow square (in LL)
Shadow square 0 - 7, Feet Every 1 feet Box Left hand bottom face of the shadow square (in LL)
Shadow square 0 - 12, Fingers Every 3 fingers Box Right hand bottom face of the shadow square (in LR)
Shadow square 0 - 12, Fingers Every 3 fingers Box Right hand vertical face of the shadow square (in LR)
Terms Zodiacal divisions, equal or unequal Not numbered  Inner Box Box 'inside' the shadow square. Common site for triplicities, etc.
The back is inscribed:
Transcription Translation Notes Type
حسب الفرموده شاه مولانا فضيلت عبد الرزاق گيلانى تمام (؟) في شهر شعبان شنه ١٠٥١ By command of the Shāh, our master, the excellent ʿAbd al-Razzāq Gilānī in Mashhad in the month of Shaʿbān in the year 1051. None
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