Very good!
One verse (4) struck me because of an incident mentioned in Koppel. The Kanakas at one gold rush site were diving in the water to bring up gold-bearing sands. The other miners took exception because they were not divers and had to dig.
I doubt that the Kanakas dove to drive piles. I think that this is imagination on someones part. But apparently there were witnesses to them diving for gold sands at the diggings.