'Watch out for the Water' and other historical sayings

On page 9 of the book Toilets through Time it tells us that when people emptied their chamber pots out of the window they would shout 'Watch out for the water!'

• Did you know that it was this saying that is thought to have given us the word 'loo'? The French for watch out for the water is 'gardez l'eau!' The l'eau sounds like 'loo' and so we started calling the toilet the loo!
• When all houses had thatched roofs, the straw on the roof was a perfect place for animals to sleep and keep warm. But when it rained, the straw became slippery and so the animals would fall off the roof. This is possibly where the saying 'It's raining cats and dogs' comes from!
• Long ago when people died, they were buried almost at once, sometimes before a doctor could see them. This led to many people being buried before they had actually died! So it was decided that they would bury people with string around their wrist tied first to a bell and then tied to a tree in the graveyard. This way, they could ring the bell and people would know that they were still alive. This is where the saying 'Saved by the bell' comes from!

What's your favourite saying? Can you find out where it comes from?