On Being Thrown Under the Bus

Anyone have a clue where the phrase “threw him under the bus” derives from? It apparently means to reveal information about a friend for personal gain, usually the friend does not deserve the treatment.

If I understand cliches I believe the original statement has to have actually meant something and quite possibly be a valid insight. Then through overuse it loses its original firm meaning.

So I ask, who exactly was thrown under the first bus and why?

I Almost Did It

I almost did a lot of things today,  right now a vacuum is sitting five feet a way from me, all plugged in ready to go. It has the potential to vacuum, I however do not plan on using it, and I do plan on telling my wife I almost did.

Saying I almost did it is very different than saying no I did not vacuum, hopefully she will think maybe I received a phone call or had some more important business to attend to.