People who wear tight hats will do well to lay this fable well to
heart, and ponder upon the deep significance of its moral:
In passing over a river, upon a high bridge, a cow discovered a broad
loose plank in the flooring, sustained in place by a beam beneath the
centre.
"Now," said she, "I will stand at this end of the trap, and when
yonder sheep steps upon the opposite extreme there will be an upward
tendency in wool."
So when the meditative mutton advanced unwarily upon the treacherous
device, the cow sprang bodily upon the other end, and there was a fall
in beef.