In Shakespeare's time, mattresses were secured on bed frames by ropes.
When you pulled on the ropes the mattress tightened, making the bed firmer
to sleep on. That's where the phrase, "goodnight, sleep tight" came from!

The "rule of the thumb" is derived from an old English law that stated
that you couldn't beat your wife with anything wider than your thumb.

It was the accepted practice in Babylon 4000 years ago that for a month
after the wedding, the bride's father would supply his son-in-law with all
the mead he could drink. Mead is a honey beer, and because their calendar
was lunar based, this period was called the "honeymoon."

In ancient England a person could not have sex unless you had the consent
of the King (unless you were in the Royal Family). When anyone wanted to
have a baby, they got consent of the King & he gave them a placard that they
hung on their door while they were having sex. The placard had F.U.#.K.
(Fornication Under Consent of King) on it. Now you know where that came
Mmmmm, very interesting post, santa.Emotion: wink I knew about where *** came from. But I didn't know about the origin of "Goodnight, sleep tight", which is a very funny expression for me.

How about these?
To be in another person's shoes -- to take someone's place. In the Viking age, when a man adopted a son, the boy accepted by putting on the man's shoes.

Done in cold blood -- done with no feeling. People believed your temper was ruled by the temperature of your blood. A hot-blooded person had a fierce temper, a cold-blooded person had no temper. So, if a cold-blooded person harmed you they did it in a calm, cruel and calculating manner.

Making both ends meet --having enough money to survive. This was a spelling mistake. In the 19th century business accounts were added up in columns. If the ends of both columns were equal then you had enough money - if they didn't then you were short of money. But the actual word used was mete - an old word for equal.
More please find the subject fascinating
Students: Are you brave enough to let our tutors analyse your pronunciation?
David, I also do find this subject fascinating. I'll post some more:

Kick the bucket -- die. In the Middle Ages a person might have tried to commit suicide by standing on a bucket then tying a noose around their neck with the end of a rope attached to the ceiling above. When they kicked the bucket away they hanged themselves.

Not worth your salt -- no good. In Roman times salt was a rare and precious mineral - like gold. So it was often used to pay the soldiers. If you weren't worth your salt then you didn't get your salt - your pay! Salt comes from a Latin word and people today are still paid a salary - a word really meaning salt.

I'm going to look for more.
Nice ones, Novalee. Imagine us being paid salt for salary. This website lists some more.
Very interseting subject!
Here
If you were to spell out numbers, you would you have to go until 1,000 until you would find the letter "A".
The expression, "tying the knot" dates to Roman times, when the bride wore a girdle that was tied in knots - which the groom then had the fun of untying.
On every continent there is a city called Rome.
In the middle ages, people would pin the name of their sweetheart to their sleeve on Valentine's Day and keep it there for a week, hence 'wearing their heart on their sleeve'.
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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