Found on the internet…
Noah’s boat finally comes to rest as the flood waters recede, and he lowers the gangway and send the animals out calling to them, “Go forth and multiply”.
Most of the animals leave, but two snakes are left behind. Noah looks at them, and commands “Go forth and multiply!”
The snakes look at him but do not move. He tries again, “Go forth and multiply!” The snakes do not move.
Noah gets angry and in his most commanding voice shouts, “Go forth and multiply!”
The snakes look up at him and say, “We can’t, we’re adders”.
Noah thinks for a while, then grabs his saw and hammer and runs off into the forest, where he cuts down a tree. He saws and hammers and builds a small table. He carefully picks up the snakes and puts them on the table.
“Go forth and multiply!” he commands.
The snakes look at each other, and then at Noah. “We can’t, we’re adders”.
“Yes”, Noah replies, “but, even adders can multiply on a log table”.
…while reading about slide rules