We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember saying something
like:

So how many people have actually been killed by a 'heater' (presumably
electric) being dropped in the bath?

According to the movies and cheesy whodunnits, lots. In reality, I've no
recall of it actually happening, but the newspapers love to perpetuate
old myths.