This reference to singing stevedores as "chanty men" connects the genre to a still earlier reference to "chanty-man" as the foreman of a work gang and the lead singer of their songs. Around the late 1840s, Charles Nordhoff observed work gangs engaged in a type of labor called "cotton-screwing" in Mobile Bay. Characterized by Nordhoff as one of the heaviest sorts of labor, cotton-screwing involved the use of large jack-screws to compress and force cotton bales into the holds of outbound ships. Work gangs consisted of four men, who timed their exertions in turning the jack-screw to songs called "chants".