Date |
984/5 or 1003/4 (A.H. 374 or
394) |
Maker |
Aḥmad and Muḥammad |
Place |
Iṣfahān |
Material |
Brass |
Inventory no. |
33767 |
Acquisition |
Presented by Lewis Evans in
1924 |
Rule, Regula, Pointer and Alidade Images
Alidade Image:
Alidade
Appearance |
Tip |
Sights |
Pinholes |
Notches |
Description |
Double-ended, original. |
Decorative |
Rigid |
Single |
None |
|
Scales
Range & Units |
Numbered |
Geometry |
Location |
Unequal
hours |
1 - 12 1/12 of daylight |
Every 1 hours |
Linear |
Rule, right arm |
Sine/Cosine |
1 - 60 1/60 of quadrant radius |
Every 5 |
Linear |
Rule, left arm |
Sine/Cosine |
1 - 60 1/60 of quadrant radius |
Every 5 |
Linear |
Rule, right arm |