-> I haven't heard from the good Dr Sprott yet,  either - I found his  
-> email and relayed your dial-drawing programme,  but have received  
-> nothing back ay yet....   hope the Remuera sun-dial in benefitting  
-> regardless. 
  
I found an earlier, and much shorter, version of that program. It just 
calculates the directions of the hour-lines on the sundial plate, 
without doing any graphics. I guess it should run on any computer that 
can handle BASIC. In case you're interested, here it is. 
  
Let me know if you hear from Dr. Sprott. 
  
                                dow 
  
---------------------------------------------------------- 
  
' SUNDIAL.BAS.  David Williams. 2001 
CLS 
DEFDBL A-Z 
PRINT "This program calculates the positions of the hour lines" 
PRINT "on a horizontal sundial." 
PRINT 
PRINT "Should the dial show lock or local olar time? "; 
DO 
  K$ = LCASE$(INKEY$) 
LOOP UNTIL K$ = "c" OR K$ = "s" 
PRINT K$ 
PRINT 
PI = 4 * ATN(1) 
PI2 = PI / 2 
DR = PI / 180 
RH = PI / 12 
PRINT "Use negative numbers for directions opposite from those shown." 
INPUT "Latitude (deg. N)"; LT 
IF K$ = "c" THEN 
  INPUT "Longitude (deg. E)"; LG 
  INPUT "Time Zone Offset (hours ahead of GMT)"; TZ 
  A0 = TZ * RH - DR * LG 
ELSE 
  A0 = 0 
END IF 
ST = SIN(DR * LT) 
PRINT 
PRINT "Hour line angles are in degrees, measured around gnomon base" 
PRINT "clockwise from poleward direction (e.g. North in N hemisphere)." 
PRINT 
PRINT "Hour", "  Angle" 
FOR X% = 5 TO 19 
  A = RH * (X% - 12) - A0 
  Q% = SGN(A * LT) 
  D = ABS(A) - PI2 
  IF ABS(D) < .0000000001# THEN 
     AZ = PI2 * Q% 
  ELSE 
     AZ = ATN(ST * TAN(A)) 
     IF D > 0 THEN AZ = AZ + PI * Q% 
  END IF 
  PRINT X%, CSNG(AZ / DR) 
NEXT 
END 
  
------------------------------------------------------------ 
--- Platinum Xpress/Win/WINServer v3.0pr5