Of course I had to inquire what Dreg Songs were and I thought you might like to know too.
Until the late 1800s the Firth of Forth was well known for it's Oysters, Dreg Songs were the songs that were sung to Charm the Oysters into the nets. It was thought these songs were lost until the day when a collection of early recordings were handed in to the Library of Congress here in America.
The following video is a must see and will tell you much more than I could ever hope to. It can be found on the Caledonia Mercury site.
For more information you can visit Bob Walser's site and follow a few other links to learn more about these fabulous songs! Enjoy :)