Hi!

rich r is entirely correct when he wrote above...
'"Navvy" may have its origin on the waterways, but the term has come to be more generic of unskilled laborers who worked on canals, roads, railroads etc.' The laborers who built the motorway system in Britain were called navvies.

I've heard the phrase "railroad navvy" as "big buck nigger" also. Stan Hugill uses "railroad nigger" and "big buck nigger" in his collection, Shanties from the Seven Seas. It's always been my assumption that what was swept under the rug in the song was an explicit reference to a sexual encounter between a working man of African origin and a white woman.

"Hog-eye?" Well, Afro-Americans, as we know, were frequently portrayed in popular media with big bulging eyes up until about 40 years ago. Maybe that's the answer. Maybe not.

Stan pretty much threw out the idea of "hog-eye" as coming from inland waterway barges.

All the best,
Dan