Spencer the Rover, a song by the Copper Family from Rottingdean, Sussex, England was a popular song of the folk circuit in the 1960s and 70's, popularized in the US by the duo John Roberts and Tony Barrand. In a previous life as a folksinger I sang it on stage, full voice. When my kids were screaming infants, I would sing the song slowly and softly to calm them at bedtime. At a slow gentle pace, it takes 5 minutes to sing all 7 verses. It helped to have this memorized, and I could just count the number of repetitions to know how long I'd been waiting for the babe to start snoring. Usually 4 or 5 times through did the trick. My children have no memory of this.