The back contains 5 scales of the following types:
Type (click to view scale details) |
Range & Units | Numbered | Geometry | Location |
---|---|---|---|---|
Zodiacal signs | 0 - 30, Zodiacal divisions, equal or unequal | Every 10 | Circular, concentric | The entire outer circle on the back of an astrolabe. |
Calendar | Days of year | days | Circular, eccentric | Circular scale immediately inside 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) |
Unequal hours | 1 - 12, 1/12 of daylight | Every 1 hours | Arc | Upper right quadrant (inside circular scales) |
Shadow square | 1 - 12, Fingers | Every 4 fingers | Box | Left hand vertical 'face' of the shadow square (in LL) |
Shadow square | 1 - 12, Fingers | Every 4 fingers | Box | Right hand vertical face of the shadow square (in LR) |
Shadow square | 1 - 12, Fingers | Every 4 fingers | Box | Left hand bottom face of the shadow square (in LL) |
Shadow square | 1 - 12, Fingers | Every 4 fingers | Box | Right hand bottom face of the shadow square (in LR) |