T -90
A 250 -108  # an arc 250 cogs, 108 degrees to the right
A 250 180   # an arc 250, 180 degrees to the left
*           # let the program to close the path
X
W 0.2       # penwidth 0.2 points
S 0.5
D 250       # disc 250 cogs
H 300       # hole 280, constant
V 90 18 20  # deviation 0, increment of deviation 18 degrees 20 times

R 50        # resolution 50 points per segment
N           # compute how many cycles will be required 
            # to close the spirogram
C 255 0 0 >  0 0 255  5   # red -> blue   5 values
+ 0 0 255 >  255 0 0  5   # blue -> red   5 values
G 10

D -250      # And now, in the outside.

G 10