The French painter George Seurat used mathematical ideas to structure his compositions. In his painting of musicians outside a circus of around 1888, now in the Metropolitan Museum of Art in New York, he included lots of horizontal and vertical lines. The effect is very calm. You can measure out La parade de cirque to discover the structure.

Seurat did not follow the lines too tightly but still made them show. The centre line goes through the trombone player – down his hat, along the line of the trombone and down his straight leg. The horizontal centre line goes through his waist, across the shoulders of the musicians to the left and along a bright horizontal line on the far right. Many objects or shapes show the golden section lines.

## Task

Work in small groups with print-outs of the image, a ruler, pens and a calculator, or find a way of measuring the image as a whole class.

- Measure the width of the picture.
- Divide the width by 1.618.
- Check the height to see if it is the figure you worked out. If it matches, you have a golden rectangle. If not, try measuring the height to the bottom of the row of gaslights. Is that area a golden rectangle?
- Use the same figure to measure across the width of the picture from each end and draw in the two vertical golden sections.
- Do parts of the composition fit your lines?
- Measure the height and divide that figure by 1.618.
- Use this figure to draw in the two horizontal golden sections.
- Do features in the picture fit your horizontal lines?

Your lines should make a grid of squares and smaller golden rectangles. Try measuring again to divide the rectangles with more golden sections and see if more objects and shapes line up.