Astrolabe Catalogue

The back contains 9 scales of the following types:

Type (click to view scale details)	Range & Units	Numbered	Geometry	Location
Degree	0 - 90, Degrees	Every 5 degrees	Circular, concentric	The entire outer circle on the back of an astrolabe.
Zodiacal signs	0 - 30, Zodiacal divisions, equal or unequal	Every 5	Circular, concentric	Circular scale immediately inside the outer scale - refers to the full circle
Calendar	first day of month - last day of month, Days of year	Every 5 days and end of the month days	Circular, concentric	Circular scale second in from the outer scale - refers to the full circle.
Unequal hours	1 - 12, 1/12 of daylight	Every 1 hours	Arc	Upper left quadrant (inside circular scales)
Sine/Cosine	0 - 90, 1/60 of quadrant radius	Every 5	Angle	Upper right quadrant (inside circular scales)
Shadow square	0 - 7, Feet	Every 2 feet	Inner Box	Left hand vertical 'face' of the shadow square (in LL)
Shadow square	0 - 7, Feet	Every 2 feet	Inner Box	Right hand vertical face of the shadow square (in LR)
Shadow square	0 - 7, Feet	Every 2 feet	Inner Box	Left hand bottom face of the shadow square (in LL)
Shadow square	0 - 7, Feet	Every 2 feet	Inner Box	Right hand bottom face of the shadow square (in LR)
Shadow square	0 - 12, Fingers	Every 2 fingers	Box	Left hand vertical 'face' of the shadow square (in LL)
Shadow square	0 - 12, Fingers	Every 2 fingers	Box	Right hand vertical face of the shadow square (in LR)
Shadow square	0 - 12, Fingers	Every 2 fingers	Box	Left hand bottom face of the shadow square (in LL)
Shadow square	0 - 12, Fingers	Every 2 fingers	Box	Right hand bottom face of the shadow square (in LR)

The back is inscribed:

Transcription	Translation	Notes	Type
صنعه علي بن ابراهيم الجزار المعذ في تازى حرسها الله سنة ذكد	Made by ʿAlī ibn Ibrāhīm al-Jazzār, the muezzin, in Tāza, may God protect her, in the year 724 (?).	Maker's inscription in upper left quadrant	Maker's signature