or “Elfenreigen” (the weird spirit-song), that music which some hear before death. Faber refers to it in his Pilgrims of the Night.
Hark, hark, my soul! Angelic songs are swelling. Pope also says, in the Dying Christian - Hark! they whisper; angels say, Sister spirit, come away.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Alpleich from Infoplease: