Or the English system of weigths and measures compaired to the metric system. Why would you use the English system? It's obsolete.

Like a mule without an ass or an ass without a mule.
For our system of measure we shall use the length of the kings foot.
Like a bull without balls or balls without a bull.
We will decide if she is a witch if she is lighter than a duck.
And let it be known across the land that a pound of gold is heavier than a pound of feathers.