And that was the end of Dan Cullen.
From that day he was a marked man, and every day, for ten years and more, he was "paid off" for what he had done.
A docker is a casual labourer.

Work ebbs and flows, and he works or does not work according to the amount of goods on hand to be moved.

Dan Cullen was discriminated against.

While he was not absolutely turned away (which would have caused trouble, and which would certainly have been more merciful), he was called in by the foreman to do not more than two or three days' work per week.

This is what is called being "disciplined," or "drilled." It means being starved.