Little Johnny took his new chemistry set down to the basement where he
stayed all afternoon mixing various liquids together. Eventually, his
dad went down and found him surrounded by test tubes, pounding
something into the wall.
"Why are you hammering a nail into the wall?" asked his dad.
"It's not a nail," said Johnny. "It's a worm! I tried to bring this
worm back to life with my special chemical mixture, but my formula
made the worm hard as a rock," he said as he showed his dad the liquid
that he had soaked the worm in.
"I'll tell you what. You give me the test tube with your special
chemical mixture in it and I'll buy you a Toyota." So little Johnny
handed the test tube over.
The next day, when Johnny got home from school, he saw a brand new
Mercedes-Benz parked in the driveway. He asked his dad about the car.
"Oh," said the father, "your Toyota is in the garage. The Mercedes is
from your mother."