Learned from Afro-American railroad workers in 1903-1905 and they of course used floating verses while spike driving. No wonder it's thematically linked with Spike Driver Blues (see there). They're like two children of the same parent. Roll On Buddy, Take This Hammer and even John Henry are also related somehow. The Nine Pound Hammers apparantly stand out with the refrain: "Roll on buddy, Don't you roll so slow, How can I roll, When the wheels won't go".
Frank Blevins & His Tar Heel Rattlers [reissued on cd Music From The Lost Provinces: Old Time String Bands 1927-1931 with recordings from the Ashe County, NC area (Old Hat); Frank was 16]
Grayson & Whitter [duo credited for cutting the original of Tom Dooley among others (see there)]
Monroe Brothers [as Nine Pound Hammer Is Too Heavy]
Merle Travis [miner song in league with his Dark As A Dungeon and Sixteen Tons (see there)]
Nitty Gritty Dirt Band [with Merle Travis]
Most covers credit Merle Travis, who by the time of these earliest recordings was only 10 years old. On Bear Family comp The Johnson City Sessions there's a Roll On Buddy from 1928 by Charlie Barnum & his Brothers, recorded by Frank Warner for Columbia.