An old man and his wife go for a walk through the countryside and they come across a fence where they used to do their courting when they were younger.
Excited by the memories of their younger days, they make love furiously, with arms and legs flailing around all over the place.
When they have finished, the exhausted woman says in a surprised tone of voice, “You know, you never used to have sex with me like that 50 years ago”.
The man replies “Well, that fence wasn’t electric 50 years ago!”
