a..mJ.o..aJ.sD.jF.mN.a..mJ.o..aJ.sD.jF
 u..aA.c..pU.eE.uE.aO.u..aA.c..pU.eE.uE
 g..yN.t..rL.pC.nB.rV.g..yN.t..rL.pC.nB
                                        su.mo.tu.we.th.fr.sa
 ......................1..2..3..4..5..6
 .1..2..3..4..5..6..7..8..9.10.11.12.13
 .8..9.10.11.12.13.14.15.16.17.18.19.20
 15.16.17.18.19.20.21.22.23.24.25.26.27
 22.23.24.25.26.27.28.29.30.31
 29.30.31

 This chart will give calendars that are the same as for mar-DEC of the
 historical Year, but the following JAN & FEB as in the Old Style year.
 Thus, all dates for March are given the same year as for its last day.

 Each month appears vertically in lower case above a column of dates,
 except when in pairs, in which case the later month is ALL CAPS. The
 column of dates underneath are those of all corresponding "Key Dates"
 (defined as all dates for which MonthIndex + Day is divisible by 7).
 Thus, the Old Style February 13th is a Key Date.

 A "Key Day" is the day of the week on which Key Dates occur in said
 span of months. Because MonthIndex + Day is divisible by 7, one may
 find the Key Day, as in Step A below. This Key Day is used in Steps B
 & C to display calendars just by sliding the row of days--by adding
 or deleting spaces to the left of 'su'. Copy & paste the chart into a
 text-editor with a monospaced font, e.g. Courier, and do as follows:

A. Calculate the Key Day:

 For a given Date in the Old Style calendar, calculate the day on which
 its Key Dates occur using (YLDM/4 + Year)/7, and apply Hans' keypad
 mapping in Reference 2, or find the remainder of the division by 7.
 (YLDM = the Year on the Last Day of the Month; / = integer division)

B. Display the calendar for March & November:

 Slide the row of days so that the Key Day rests over 28 thereby
 showing the calendar for the March that began the Year with Lady Day.
 One has as well the calendar for the following November.

C. Display calendars for the other months:

 for any month other than March or November: slide the row of days
 to put the Key Day under the month to be displayed.


Q. How would you modify this for the Julian or Gregorian Calendar?

 (There's more than one right answer.)

--

      REFERENCES

http://www.angelfire.com/my/zelime/calendarslide.html
gopher://gopherite.org/0/users/retroburrowers/TemporalRetrology/cc/jg