Here is a couple of pictures I took in an elderly dairy shed here some months back.

The yellow wire you see, is actually a length of 3 core extension cord.

Some idiot has stripped back the Main earthing lead (with a blunt knife by the looks of it) and hooked up this abomination, using a split-bolt:

[Linked Image from electricalphotos.com]

Here is the other end of this great idea, it "connects" to the metal framing of what is known as a milk cooler, these don't need earthing at all and I have no idea why this was necessary in the first place!:

[Linked Image from electricalphotos.com]

Mike.