Rule, Regula, Pointer and Alidade Images
Alidade Image:
| Date | ca. 1700 |
| Maker | Khalīl Muḥammad ibn Ḥasan ‘Alī |
| Place | Iṣfahān |
| Material | Brass |
| Inventory no. | 50987 |
| Acquisition | Presented by J. A. Billmeir in 1957 |
Alidade
| Appearance | Tip | Sights | Pinholes | Notches | Description |
|---|---|---|---|---|---|
| Double-ended, original. | Simple | Rigid | Double | None |
Scales
| Type | Range & Units | Numbered | Geometry | Location |
|---|---|---|---|---|
| Degree | 0 - 60 1/60 of quadrant radius | Every 5 | Linear | Rule, left arm |