Once upon a time, people lived in houses with thatched roofs.
the straw was thick, and piled high, with no wood underneath.
It was the only place for animals to get warm, so all the cats and other small animals (mice, bugs) lived in the roof space.
When it rained, it became slippery and sometimes the animals would slip and fall off the roof.
Hence the saying - it's raining cats and dogs.

And there was nothing to stop things from falling into the house..
This posed a real problem in the bedroom where bugs and other critters - like cows? - could mess up your nice clean bed.
So some bright spark hit on the idea of having a quiet night's sleep by making a bed with big posts and a sheet hung over the top.
That's how canopy beds came into existence.

None of these advances have helped me much, I have to say.
I am regularly disturbed at bed time by doris jumping on me from the top of the wardrobe.

(as you may have noticed, this was the third of our history lessons, which is why i put a number three in the title.)
you can find the previous two historic posts by clicking on the history tag (which is hiding behind the 'more tags' tab at the top of this historic blog.)

clever, eh?