Efficiency Wages?

`It's only once a year, sir,' pleaded Bob, appearing from the Tank. `It shall not be repeated. I was making rather merry yesterday, sir.'

`Now, I'll tell you what, my friend,' said Scrooge,' I am not going to stand this sort of thing any longer. And therefore,' he continued, leaping from his stool, and giving Bob such a dig in the waistcoat that he staggered back into the Tank again;' and therefore I am about to raise your salary.'