Date |
17th century |
Place |
India |
Material |
Brass |
Inventory no. |
33411 |
Acquisition |
Presented by A.E. Gunther in
1986 |
Rule, Regula, Pointer and Alidade Images
Alidade Image:
Alidade Image:
Alidade
Appearance |
Tip |
Sights |
Pinholes |
Notches |
Description |
Double-ended, original. |
Simple |
Rigid |
None |
None |
This alidade
has a sighting rule
like many of the Indian instruments. The alidade might be
a later replacement; the metal is distinctly
different. |
Scales
Range & Units |
Numbered |
Geometry |
Location |
Sine/Cosine |
0 - 60 1/60 of quadrant radius |
Every 6 |
Linear |
Rule, right arm |
Unequal
hours |
1 - 12 Times of day |
Every 10 hours |
Linear |
Rule, right arm |