In his poem “The Nature of Electricity” quoted by Kinbote (in VN’s novel Pale Fire, 1962, Shade’s mad commentator who imagines that he is Charles the Beloved, the last self-exiled king of Zembla) in his Commentary Shade mentions “Shelley’s incandescent soul:”
The light never came back but it gleams again in a short poem "The Nature of Electricity," which John Shade had sent to the New York magazine The Beau and the Butterfly, some time in 1958, but which appeared only after his death: