Sunlight is the life-blood of Nature. Mother Earth looks at us with such dull, soulless eyes, when the sunlight has died away from out of her. It makes us sad to be with her then; she does not seem to know us or to care for us. She is as a widow who has lost the husband she loved, and her children touch her hand, and look up into her eyes, but gain no smile from her.Jerome K. Jerome, Three Men in a Boat (London: Collins Classics, 2013; 1889), p. 205.