Astrolabe Catalogue

The back contains 11 scales of the following types:

Type (click to view scale details)	Range & Units	Numbered	Geometry	Location
Altitude	0 - 90, Degrees of arc	Every 5 degrees	Circular, concentric	Upper right quadrant of outer circular on back of instrument.
Altitude	0 - 90, Degrees of arc	Every 5 degrees	Circular, concentric	Upper left quadrant of outer circular on back of instrument.
Sine/Cosine	None	Not numbered	Angle	Upper left quadrant (inside circular scales)
Declination	None	Not numbered	Arc	Upper right quadrant (inside circular scales)
Cotangent	Fingers	Every 5 fingers	Circular, concentric	Lower right quadrant of outer circular on back of instrument.
Cotangent	Feet	Every 5 feet	Circular, concentric	Lower left quadrant of outer circular on back of instrument.
Terms	Zodiacal divisions, equal or unequal		Inner Circular, concentric	half circle inside the outer circle (on mashriqi astrolabes) - covering LL and LR
Zodiacal signs	Zodiacal divisions, equal or unequal		Inner Circular, concentric	half circle inside the V circle (on mashriqi astrolabes) - covering LL and LR
Faces	Astrological face		Inner Circular, concentric	half circle inside the VI circle (on mashriqi astrolabes) - covering LL and LR
Lunar Mansions	Lunar mansion		Inner Circular, concentric	half circle inside the VII circle (on mashriqi astrolabes) - covering LL and LR
Shadow square	None		Box	None
Triplicities	Zodiacal divisions, equal or unequal		Inner Box	Box 'inside' the shadow square. Common site for triplicities, etc.

The back is inscribed:

Transcription	Translation	Notes	Type
العلي عبد صنعه	‘Abd al-‘Ali made this		Maker's signature