I'm bored so I'll take a moment to wax a bit nostalgic here and the information I now post is secondhand, from my dad.
Many years ago, my grand pap bought a line of Black Australorps from a hatchery Situated (I think) in Windsor Mo, called Marti's Hatchery. The birds were huge, pumped out huge dark brown eggs like a Leghorn and had a very long and useful lifespan. Those folks are no longer in business but if I had been old enough at the time to understand what a treasure pot was there, I would have kept some of those birds and I would have them to this day.
I'm wondering if any older folks on this thread ever got any of those birds from Marti's? I kinda' doubt it because I'd have heard about it on this thread or another. My dad and grand dad crossed them with NNs and produced some large magnificent layers but they should have kept that strain of pure unadulterated Australorps at any cost.
Spilled milk. I truly hope someone was smart or lucky enough to have done what my dad lamented having not done for so many years after failing to see what they had.