HERE'S a general knowledge question to get the old grey cells going.

Which invention was dreamed up by an asthmatic janitor and comprised a tin soap box, a fan, a sateen pillow case and a broom handle?

If you said the Hoover vacuum cleaner, give yourself a pat. If you remembered that the janitor's name was Murray Spangler, then you're my phone-a-friend if I ever get on Millionaire.

Spangler quickly realised that this "suction sweeper," as he called it, had enormous sales potential, and he began seeking financial backing.

His cousin, Susan Hoover, agreed to try the machine in her home. Before long, she was singing its praises to husband, W H "Boss" Hoover, owner of a leather goods manufacturing shop. Hoover bought the patent from Spangler in 1908, retained him as a partner and the rest is history.

Many of us still refer to our vacuum cleaners as Hoovers, even though I'll wager that many of us have been lured away to Dyson, whose bagless cleaners have been flying out of electrical retailers as fast as James Dyson can make them.

I mention all this for two reasons. Firstly, my wife would gladly trade in her husband before her Dyson. Secondly, a man in Scotland is trying to sue Dyson because he says his vacuum cleaner attacked him.

The first point is irrelevant and only goes to show that women prefer a spotlessly clean house to a spotlessly clean, well-mannered and loving partner.

However, I am fascinated by the idea that 57-year-old Norman Grant from Aberdeen managed to get into difficulty with his Dyson. (I'm sure there are men out there who are wondering why Norman was at the helm of the cleaner in the first place, but I'll skirt round that thorny issue).

It appears Norman was thrown down the stairs and knocked unconscious when the hose connection on his new cleaner shot out and hit him.

He subsequently suffered a broken wrist, a twisted neck and a strained back and has not been able to play golf or work since.

Dyson is contesting the matter and vehemently stresses that it places user safety at the forefront of its operation.

But for those of us whose experience of dealing with vacuum cleaners only ever involves their removal from, and return to, their place of rest, the thought that the things are out to get us sounds like a fantastic excuse for the future.