Screw-gun Mules

As me and my companions were scrambling up a hill,
The path was lost in rolling stones, but we went forward still;
For we can wriggle and climb, my lads, and turn up everywhere,
And it's our delight on a mountain height, with a leg or two to spare!

Good luck to every sergeant, then, that lets us pick our road!
Bad luck to all the driver-men that cannot pack a load!
For we can wriggle and climb, my lads, and turn up everywhere,
And it's our delight on a mountain height, with a leg or two to spare!