Procedure for making Permanent Calendar (अक्षय्या दिन-दर्शिका)
1) Take two A4 size papers. Mark the centres by joining diagonals.
2) Draw 10 concentric circles with radii 30, 38, 46, 54, 62, 70, 78, 86, 94, 102 mm
3) Draw diameters at every 100 angle
4) On one paper, say paper A between circles of radii 30 and 38, in every 100 segment write names of days SUN MON TUE WED THU FRI SAT. We have 36 segments. So, we can write five cycles of these.
5) On this paper A names of months as shown in the table
Note :- The months (JAN) and (FEB) in the last column are for LEAP YEARS
6) On the other paper B choose any seven segments and in spaces between circles 38-46 write numbers 1 to 7 in counter-clockwise order, when looking at the circles from outermost circle to innermost. In this manner complete date numbers up to 31 as shown in the table
In spaces between circles
1 to 7
8 to 14
15 to 21
22 to 28
29, 30, 31
7) From paper A cut off all paper outside of circle of radius 78
8) From paper A cut off also paper outside of circle of radius 38, BUT not from the seven segments on which names of months are written.
9) Now, prick a pin at the centre on both papers. Use the pinholes to match the centres of both papers, putting paper A above paper B.
10) Turn paper A around the pin to bring month AUG and weekday SUN opposite to AUG to match with Date ‘1’. In the space on paper B, above AUG in the space between circles 78-86 write by PENCIL “2010”
11) Again turn paper A around the pin to bring DEC below “2010”. It will be seen that 31 DEC 2010 will be FRI
12) Turn paper A around the pin to bring SAT above Date 1. In the segment on paper B above JAN write in the space between circles 78-84 “2011”
13) Turn paper A to bring DEC below “2011”. It will be seen that 31 DEC 2010 will be SAT.
14) Turn paper A around the pin to bring SUN above Date 1. Now since 2012 will be a Leap year, we have to write “2012” above (JAN)
15) To know the calendar for FEB 2012 we have to match (FEB) with 2012.
16) By this logic we can mark years from 2001 to 2099. When two years wil fall into one and the same segment, write the larger year number above the previous one. That is why we have circles of radii 94 and 102 also.
17) For years 2000 and older, we may need more space on paper B and hence circles outside of circle of radius 102. You can make a new larger calendar with adequate space, once you get the hang of it.
18) It will be better to check the year-markings against calendars available in most computers, especially 1 JAN of each year. Once this is correct, everything will be correct. That is why see in item 10, the caution write by PENCIL underlined.
Please do try by yourself !