A snake goes to the optometrist one day. "I've been having a bit of trouble with my eyesight lately," he says. "And it's been making it very difficult for me to chase and catch rats."

The optometrist then gives him an eye test and prescribes a pair of glasses; the snake then thanks the optometrist and leaves. A few months later, the snake comes back for a check up and the optometrist asks him how his new glasses have been.

"Oh, wonderful!" the snake replies happily. "I can see better than ever now and my rat catching prowess has more than doubled! However... now I'm depressed."

"Depressed?" the optometrist asks, perplexed. "Why?"

"Well, since I got them, I found out that I'd been in love with a garden hose all this time."