A man went to see his doctor about a pain in his arm. The doctor was busy, but the nurse offered to let him use a new automatic diagnostic device.
"How's it work?" the man asked.
"Well," the nurse replied, "just pee into this sample device, pour it into the machine, and it'll tell you what's wrong."
The man was skeptical, but he followed the instructions. After a few minutes of humming, the machine spat out a printout that said, "You have tennis elow."
"Tennis elbow?" the man asked. "How can it possibly find 'tennis elbow' from a urine sample?"
"All I know is, the machine is never wrong!" the nurse said.
The man took an extra sample container and went home, determined to show the machine up. He managed to collect urine samples from his wife, his daughter, and his dog; he drained some oil from the crankcase of his car; and he masturbated into the container. The next day, he went back and put the sample into the machine. It hummed, then chugged, then spat sparks, and finally produced a printout:
"Your wife is having an affair with the mailman, your daughter is pregnant, your dog has worms, your car needs a tuneup, and if you don't stop playing with yourself, you'll never get over that tennis elbow!"
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.