What a beautiful write up! Thanks for giving an exposition on earthing. I've also experienced a similar situation too at home before. I noticed that whenever it's raining and thunder strikes, the electrical socket do sparks and as a result destroys whatever appliance that's being connected to it. Not until I took a tester and noticed that the earthing of the house is electrified. I had to check around where the house was earthed and noticed that the earthing wire was hanging loose outside the ground and was also disconnected from the corper block that's supposed to absorb the excess electric discharges.

One more thing is that, aside for electrical appliances, earthing is also good in protecting the house and its electrically connected gadgets from thunder strike. That's why you usually see some houses with protruded three-pointed-like sharp object facing the sky at the topmost part of the building. A thin wire is connected to it and buried on a copper block or plate inside the earth. This is meant to absorb the excess electric current from the resulting lightning and thunder.