I've got a mule, her name is sal,
fifteen miles on the erie canal.
she's a good old worker and a good old pal,
fifteen miles on the erie canal.
we've hauled some barges in our day,
filled with lumber, coal, and hay,
and every inch of the way we know
from albany to buffalo.
low bridge, everybody down!
low bridge, for we're coming to a town!
and you'll always know your neighbor,
you'll always know your pal,
if you've ever navigated on the erie canal.
we better get on our way, old pal,
fifteen miles on the erie canal.
'cause you bet your life i'd never part with sal,
fifteen miles on the erie canal.
get up there, mule, here comes a lock,
we'll make rome about six o'clock,
one more trip and back we'll go,
right back home to buffalo.

1) what animals in this poem mostly about? use details from the poem to support your answer.