Lyrics:

Once upon a time there was an engineer.
Drove a locomotive both far and near.
Accompanied by a monkey that would sit on a stool
Watching everything the engineer would do
One day the engineer wanted a bite to eat,
He left the monkey sitting on the driver's seat,
The monkey pulled the throttle, the locomotive jumped the gun
And did 80 miles an hour down the mainline run.

Big locomotive right on time, big locomotive coming down the line.
Big locomotive No. 99, left the engineer with a worried mind.

The engineer called up the dispatcher on the phone,
To tell him all about his locomotive was gone.
Dispatcher got on the wire, switch operator to the right,
Cause the monkey's got the main line sewed up tight.
The switch operator got the message on time,
Said there's a Northbound livin' on the same main line,
Open up the switch I'm gonna let him through the hole,
Cause the monkey's got the locomotive under control.

Big locomotive right on time, big locomotive coming down the line.
Big locomotive No. 99, left the engineer with a worried mind.