Originally, yes. So were aspirin, heroin, kerosene, hovercraft, linoleum, and a bunch of other common words.

It is not. “Gasoline” is what Brits should call the substance they put into their vehicles. Petroleum is not what goes in them, that is just an unrefined version of gasoline.

Edit: Petroleum, not patroleum.

The brand was cazeline, according to https://en.wikipedia.org/wiki/Gasoline#Etymology