"Johnny's on the Water" is a song from Jean Ritchie's book The Dulcimer Book. She indicates that it is in Phryigian mode but since the tonic note appears to be A and there is no second note used in the melody, it could be considered to be minor. Ritchie accompanied it in a Phryigian mode tuning on the dulcimer. The dulcimer tablature given here follows her example. She gives no background or historical notes except that it was sung at the Campbell Folk School in Brasstown, North Carolina. The school was established in 1925 by folk song collector Olive Campbell in memory of her late husband John C. Campbell who was an educator and social reformer in southern Appalachia. I can't find any reference to this anywhere. There are children's game/songs called "Charlie's on the Ocean" and "Charlie Over the Water" but they appear to be unrelated. Except for the first verse, the song seems to be a reworking of "On Top of Old Smokey" with one unrelated verse from "The Cuckoo Bird". It appears on the re-release CD Jean Ritchie on Mountain Hearth & Home : Jean Sings The Songs Of Her Kentucky Mountain Family (2004).