According to my notes:
Tom Anderson (1910-1991) was born in Eshaness on the north-western mainland of Shetland. Widely known as a player, composer, teacher and authority on the music of his native Shetland, Tom was a tireless worker in the cause of traditional music.The Sixereen is the Shetland six-oared open boat shaped like a Norse galley. Tom composed this tune in 1947, while watching this vessel crossing the bay.