Hundreds of years ago ...
England is old and small and the local folks started running out of places to bury people. So they would dig up coffins and would take the bones to a “bone-house” and reuse the grave. When reopening these coffins, 1 out of 25 coffins were found to have scratch marks on the inside and they realized they had been burying people alive. So they thought they would tie a string on the wrist of the corpse, lead it through the coffin and up through the ground and tie it to a bell. Someone would have to sit out in the graveyard all night (the “graveyard shift”) to listen for the bell; thus, someone could be “saved by the bell” or was considered a “dead ringer.”
In those old days, they cooked in the kitchen with a big kettle that always hung over the fire. Every day they lit the fire and added things to the pot. They ate mostly vegetables and did not get much meat. They would eat the stew for dinner, leaving leftovers in the pot to get cold overnight and then start over the next day. Sometimes the stew had food in it that had been there for quite a while. Hence the rhyme, “Peas porridge hot, peas porridge cold, peas porridge in the pot nine days old.”
Houses had thatched roofs-thick straw-piled high, with no wood underneath. It was the only place for animals to get warm, so all the dogs, cats and other small animals (mice, bugs) lived in the roof. 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.”
There was nothing to stop things from falling into the house. This posed a real problem in the bedroom where bugs and other droppings could really mess up your nice clean bed. Hence, a bed with big posts and a sheet hung over the top afforded some protection. That’s how canopy beds came into existence.