After having their 11th child, an Irish couple decided that was enough, as they could not afford a larger bed.

So the husband went to his doctor and told him that he and his wife didn't want to have any more children. The doctor told him there was a procedure called a vasectomy that would fix the problem but it was expensive. A less costly alternative was to go home, get a firework, light it, put it in an empty beer can, then hold the can up to his ear and count to 10.

The husband said to the doctor, "B'Jayzus, I may not be the smartest guy in the world, but I don't see how putting a firework in a beer can next to my ear is going to help me."

"Trust me, it will do the job", said the doctor.

So the man went home, lit a banger and put it in a beer can. He held the can up to his ear and began to count: "1, 2, 3, 4, 5," at which point he paused, placed the beer can between his legs so he could continue counting on his other hand.

Owch.