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— Mobile Sun-Dials —

We usually find sun-dials on the walls of buildings or on the tower of churches. But what did man do in the Middle Ages when he or she was travelling? Beautiful times not to be stressed by the fear to miss the train. However, everybody who was anybody had of course, like today, his or her «mobile». Very environment sensitive, powerd by the sun exclusively – with the disadvantage (?) of timelessness when the sky was clouded and at night.

During some visits to the mediaeval town of Carcasson in Southern France I purchased a couple of replica of portable sun-dials. A good investion as it turned out: I haven't had to change any batteries yet …

Note on Usage: Either select the desired type from the list in the column at left — or simply click on the sun-dial in the picture at right.

Time Equation
The Time Equation shows the difference between the «True Sun» and the «Medium Sun». Minutes (Min) rounded and shown for each 15 days.

   Date Min    Date Min    Date Min    Date Min   
   01. Jan - 03    01. Apr - 04    01. Jul - 03    01. Oct + 10   
   15. Jan - 09    15. Apr +- 0    15. Jul - 06    15. Oct + 14   
   01. Feb - 14    01. May + 02    01. Aug - 06    01. Nov + 16   
   15. Feb - 15    15. May + 03    15. Aug - 05    15. Nov + 15   
   01. Mar - 13    01. Jun + 03    01. Sep +- 0    01. Dec + 11   
   15. Mar - 09    15. Jun +- 0    15. Sep + 04    15. Dec + 05   
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