Hemisferium

For sale 1940’s reproduction of an 18th century perpetual calendar. A perpetual calendar is a calendar that is valid for many years. Usually it allows the determination of a day or a week in the past or the future. This perpetual calendar is valid from January 1, 1600 until December 31, 2799 according to the Sunday letter system. To determine which day of the week for June 29, 1900 falls (from the birth of Antoine de Saint-Exupéry), first the Dominical letter for the year 1900 must be discovered. On the back of the calendar (lunar side, second image above) appears the letter G at the intersection of 19 (on the small century disc) and 00 (on the base disc). In the next step the perpetual calendar is set in rotation. If you rearrange the month of June (on the mobile disk) before the Sunday letter G, V, you can read the day of the week (in Latin Veneris, Friday on German) in column 29. Attention to detail, historical interest and beauty of form characterize this beautiful perpetual calendar. It comes without base. Weight: 330 gram Diameter: 90 mm