At the South-Eastern end of Grasmere in the Lake District there is a small step down in the water level. A weir. Less than a foot in height, but on a still day the water is transformed from a barely rippled sheen into a minor torrent as it overflows into the River Rothay. The river then winds its way to Rydal Water, and from there to Ambleside where it drains into Lake Windermere, the largest body of water in the Lake District.
My eye was attracted by the contrast in the water above and below the weir.