Illuminated Manuscript Carpet Pages

The Geometric Framework for an illuminated painting of a Christian Cross

The first circle

1) Draw a horizontal line. This will be the horizon line that the whole drawing is based on.

 

2) Open the compasses to  about 4 cm. Measure this against a ruler. Place the point of the compasses in the paper at the horizon line. Holding the top of the compasses, draw a circle.

 

3) Move the compasses to the point where the circle cuts the horizon. Make sure that the arms of the compasses are still open at the same distance. Holding the top of the compasses, swing an arc that is just over a semicircle in size.

 

4) Move the compasses to the other side, where the circle cuts the horizon and repeat.

 

5) Now you need to add the vertical line. If you have a set square, use this. Otherwise, move the compasses to the point where the arc of the semicircle cuts the line of the main circle (highlighted in blue). Swing a small arc. Repeat on the other three intersections. Carefully line up the ruler with the points where the two sets of (blue) arcs cross. Draw a line between them.

 

6) With the compasses still at the same radius as the very first circle, move them to the point where the vertical line cuts the main circle. Draw a semicircle. Repeat at the other point, where the vertical cuts the main circle. This gives four ‘petals’. These shapes are known as Vesicas.

Extending the diagonal

7) Line up your ruler across the top of the circle. Draw a line across the top of the circle, from vesica to vesica.


8) Now, line up your ruler across the right hand side of the circle and draw a line across the side of the circle, from vesica to vesica. Extend this line for a little way beyond 

the base of the circle.

9) Repeat on the left hand side.

10) Place the point of the compasses at the very tip of the upper, right hand vesica (ringed in blue). Open the compasses to the very tip of the bottom, left hand vesica (i.e., along the diagonal). Swing an arc so that it cuts the vertical line on the right.

11) Repeat on the other side.

12) Line up your ruler across the bottom of the two arcs, where they cut the laft and right hand vertical lines. Draw a line across. This forms the bounding frame for the painting. The sides of the rectangle are in the proportion 1: √2

Subdivide the page using nested squares

13) Inside the main circle, line up your ruler across the North and East points. Draw a line to join them. Line up your ruler across the East and South points. Draw a line to join them. Repeat with the other two sets of points, South & West and West and North. You now have a square.

14) Now repeat the process, but joining NE to SE, SE to SW, SW to NW and NW to NE. You now have two squares that form an 8 pointed star.

15) Inside these two squares, repeat the above steps. Join the points where the diagonal, horizontal and vertical lines cut the sides of the two squares.

16) Repeat this process again, inside the two, new squares. Repeat once more. This should give you four sets of nested squares.     

Forming the Cross

17) Inside the smallest, nested square, place the point of the compasses at the intersection of the main vertical and horizontal lines, at the very centre of the square.

18) Open the compasses so that the lead just touches the side of the small square. Draw a circle.

19) Keeping the compasses open at the same radius, move the point of the compasses to the point where the central vertical line cuts the side of the biggest square that is inside the circle. This point is marked in blue on the diagram.

20)Draw a circle. Repeat at the opposite side.

21) Move the point of the compasses to where the central horizontal cuts the side of the biggest square that is inside the circle. With the radius the same as before, draw a circle.

22) Repeat on the opposite side.

23) Now move the point of the compasses to the NE corner of the biggest square inside the circle. Open the arms of the compasses along the diagonal, so that the lead touches the SW corner of the same square.

24) Draw an arc so that it cuts the right hand vertical line.

25) Move the compasses to the NW corner. Open them along the diagonal, to the SE corner and draw another arc. Repeat steps 23 &24 but with the square that surrounds the largest circle.

Draw a line across to these two new arcs to complete the outer, bounding rectangle.

The proportions of the Cross

26) Draw a light line across these two arcs (dashed line in the diagram). Place the point of the compasses at the point where the central vertical line crosses it.

27) With the compasses at the same radius as the small circles drawn insteps 18 - 22, draw an arc across the central vertical line.

28) Move the compasses to the point where this new, small arc cuts the central vertical line. Draw a circle.

29) With the same radius, draw a circle at each of the four corners of the outer, bounding rectangle.

30) Inside the central, small circle, draw a square by joining the NESW points at the central horizontal & vertical lines. Inside this draw another square across the NE, SE, SW,NW points where the diagonal lines cut the sides of the square.

31) Draw another square inside this, across NESW and another inside this across NE SE SW NW.

32) With the point of the compasses at the very centre of the nested squares, draw one circle inside the very smallest square and another around the 2nd square.out.

33) Draw circles of these two radii inside the other circles. The circles at the four corners of the bounding rectangle only need the larger of the larger of these two circles

Adding the arms of the cross

34) Add a further circle around the outside of each one of the 6 main circles of the cross. Put the point of the compasses at the centre of the Northern most circle of the cross. Open the arms of the compasses so that the lead just touches the side of the bounding rectangle. Draw a circle.

35) Repeat at each of the other circles of the cross.

36) Draw in the lines of the arms of the cross. Place your ruler across the top of the arc of the smallest circles on the central horizon line. Draw a line from the left hand red circle to the edge of the central red circle. Repeat on the right side. Align the ruler with the base of the smallest green circles and repeat.

37) Align the ruler along the top of the 2nd smallest green circles on the central horizon line. Draw a line from the edge of the big, green circle on the left, to the edge of the central big, green circle. Repeat on the right side.

38) Align the ruler across the left sides of the smallest green circles on the central vertical. Draw a line from the edge of one red circle to the next. DO NOT CONTINUE THE LINE ACROSS THE CIRCLES.

Repeat on the right side.

39) Align the ruler across the left sides of the 2nd smallest green circles. Draw a line from the edge of one big, green circle to the next. Repeat on the right side.

40) The group of arcs at the top and bottom of the bounding  rectangle are optional. The radius is the same as the red circles of the cross. The points for the compass are shown ringed in blue. Find the middle of the space within the arch and draw a small circle so that it touches the arch and the side of the bounding rectangle.

Completing the structure of the Cross

41) To Draw the stepped corners, line the ruler up across the top of the red circles at the four corners of the bounding rectangle. Draw a light line across, from one to the other. Repeat on the other three sides. Align the ruler across the top of the green corner circles and draw a light line from one to the other. Repeat on the other 3 sides.

42) Determine how big these corners are to be. Here, they are lined up with the smallest green circles in the arms of the cross and this measure is then transferred to the other steps with the compasses or a pair of dividers.

43) The arms of the cross can be finished in a variety of ways and a few examples are given here and on the next page. Whatever way you choose, think of the shape of the spaces either side of the arms. The more convoluted the shape, the harder it will be to fill with a pattern.

44) The green grid here shows one way of dividing up the space. The lines of the grid are extensions of the sides of the spade like ends of the arms of the cross. The sub-divisions can be found by measuring or extending lines from the small, green circles. The way that you divide the grid will be largely dictated by what pattern you want to put in the space.

45) Once you have established the layout of the framework, put a piece of tracing paper over it and work out the grid on that. If you make a mistake, or don’t like the result, simply discard the tracing paper and start again. I always end up with layer upon layer of tracing paper.

Examples of Illuminated Cross Carpet Page
Cross with Square Terminals

The  spaces around the red cross are much easier to fill than those surrounding the black/green cross.
A large space can always be further divided. For example, adding a box frame inside the space. With an awkwardly shaped space, this has the advantage of providing a much more regular space for the main pattern and leaving just an awkward border to fill.
Once you have the geometry for a framework, experiment with different layouts by placing tracing paper over it and seeing how many ways it can be developed.
Many of the famous illuminated gospel pages share a geometric framework.

See a finished example of a Celtic Cross Carpet Page

Cross structure with eight pointed stars
  • Pinterest Social Icon
  • Facebook Social Icon
  • Google+ Social Icon
  • Instagram Social Icon
  • LinkedIn Social Icon

© Diane George 2018 illuminatedpages@btinternet.com

39 Stepney Road, Burry Port,SA16 0BE