Those are my rowing songs for 1830s. Now, some firemen's songs from that decade. I am not sure of the exact nature of work of the (mainly Black) "firemen" on river steamboats. Were they shoveling in coal, as on a locomotive? Was it logs they threw into a furnace, down below? More info, please! Whatever the case, the environment evokes the phrase, "Fire down below."

THE RAMBLER IN NORTH AMERICA, 1832-1833, Vol 2., by CJ Latrobe, 1835.

Of a steamboat on the Ohio River, mentions "the wild song of the negro fire-men." (pg 281).

Next, a dramatic scene in BENTLEY'S MISCELLANY, vol 4, New York, Sept. 1839,
taking place in a steamboat. Here's the song.

"THE STOKER'S CHAUNT.
The ebben tide ib floating past,
Fire down below!
The arrival time ib coming fast.
Fire down below!
Racoon cry in de maple tree,
Fire down below!
The wood ib on fire, and the fire a sea,
Fire down below!
Oo a oo oh ! fire down below!"

A chaunty? It appears to be related to a "fire down below" chantey that will continue to appear in the 19th century. Here is a rendition of the chantey as culled by Hugill, if one would like to fit the above lyrics to the framework:

The Sailor Fireman

Incidentally, Hugill cited it as a possible source for the melody to the chantey "Sacramento."