A Straight Line over Arcs

One summer night I and some friends stopped by this stone arc bridge on Mississippi river.  When we were walking along the river, I was suddenly attracted by the structure of the bridge – a perfect combination of curve and the straight bridge edge above.

I snapped the picture, just as they were without any editing.  Later whenever I looked at the picture, I always remember a Chinese proverb, the world is built by mixing curved shapes and straight lines, with certain norms and standards.

Structure