The second verse goes like this:

We will camp tonight at a pleasant site,
and we'll sing to the banjo's strum.
To the fiddle's squeal, we will dance a reel,
and be happy all the night long.
Roll Along, Wagon Train. Roll Along, Wagon Train,
Roll Along Wagon Train, Roll Along across the Plains.

(It's funny, but I remember all of the second verse, but only part of the first verse. We sang this in Elementary School chorus about 1957.)