Set back from the coastal path in Devon is a pool overhung on one side by trees and opening, on the other, on the hill surmounting Baggy Point. The water was covered to the right by dense weeds and on the left by a carpet of floating algal bloom. I sat in the shade and sketched this, scowling to ward off interested passers by. I failed. A family arrived with a dog that threw himself into the water with gusto to be dragged out reluctantly. Very slowly, the algal surface moved to cover again the opened water.