The back contains 6 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 | outermost scale on the front of the limb |
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 | Days of year | days | Circular, concentric | None |
Unequal hours | 1 - 6, 1/12 of daylight | Every 1 hours | Arc | Upper left quadrant (inside circular scales) |
Unequal hours | 1 - 6, 1/12 of daylight | Every 1 hours | Arc | Upper right quadrant (inside circular scales) |
Shadow square | 1 - 12, Fingers | Every 2 fingers | Box | Left hand vertical 'face' of the shadow square (in LL) |
Shadow square | 1 - 12, Fingers | Every 2 fingers | Box | Right hand vertical face of the shadow square (in LR) |
Shadow square | 1 - 12, Fingers | Every 2 fingers | Box | Left hand bottom face of the shadow square (in LL) |
Shadow square | 1 - 12, Fingers | Every 2 fingers | Box | Right hand bottom face of the shadow square (in LR) |
Transcription | Translation | Notes | Type |
---|---|---|---|
الحمد لله هذا الأسطرلاب حبس على المسجد الأعظم من ثغر طنجة علاه الله بمنه آمين | Praise be to God. This astrolabe was given as a bequest to the Grand Mosque of the port of Tangiers, may God elevate it with His grace. Amen. | Miscellaneous |