Lightning my pilot sits; In a cavern under is fettered the thunder, It struggles and howls at fits; Over earth and ocean, with gentle motion, This pilot is guiding me, Lured by the love of the genii that move In the depths of the purple sea; Over the rills, and the crags, and the hills, Over the lakes and the plains, Wherever he dream, under mountain or stream The Spirit he loves remains; And I all the while bask in heaven's blue smile, Whilst he is dissolving in rains.
Percy Bysshe Shelley (1847). “The works of Percy Bysshe Shelley, ed. by mrs. Shelley”, p.259