If the original lyrics of "Call of the North" include 'Glindawor', I suspect that could be the name of a real or fictitious sheep station. Joe has referenced Jack Sorensen's book 'The gun of Glindawor and other ballads'. (The "gun" is the best, top, fastest, etc, shearer working in a shearing shed.)

In the version found at http://folkstream.com/181.html, Mullewa is a small town 450km north of Perth, so perhaps that's where the "call" was coming from. It's certainly north of many other places.

For some reason, the the Wongawilli version prefers to include Glendalough, which is the name of a suburb in north Perth. Coincidentally (or maybe not), Bob Rummery, the composer of the tune used by Wongawilli, lives about 15km from Glendalough.

I think Martyn W-R might be using his own tune.