Milkman to new hand: “Did you put water in the milk this morning?”
New hand: “Yes sir. “
Milkman: “Don’t you know this is wicked?”
“But you told me to mix water with the milk?”
“Yes, but I told you to put the water in first and then pour the milk into it. Then, you see, we can tell the people we never put water in our milk. “
This joke is included in the Black Book of Jokes. You can order it from here.