Astrolabe Catalogue

 

The calendar is of the Western type. Every tenth day and the last day of the month.The vernal equinox falls on the 9th day of March. [N.B: Date is decimal as date of vernal equinox on some astrolabes can be measured to within 0.25 of a day]Note the error in January. Initially, the maker indicated that there were 30 days in January. He then corrected it.
The calendar is labelled:
Month of the year Labelled on astrolabe
1. January : Ianuari
2. February : Februa
3. March : Marci
4. April : Aprili
5. May : Maius
6. June : Iunius
7. July : Iulius
8. August: August
9. September : Septem
10. October : October
11. November : Novem
12. December : Decem
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