Life's Little Mysteries

Are England and France moving apart due to shifting tectonic plates? If so, what will happen to the Chunnel?

The Earth is made up of about 12 plates that range in thickness from around 200 kilometers for oceanic plates to 150 kilometers for continental ones. The plates are rigid and rest on a more fluid layer underneath.They slide over this fluid layer, jostling with one another, forming mountain ranges over time when they collide and earthquakes when they slide against one another. Most plates move at a rate of about two centimeters a year.

France and England are part of the Eurasian plates, so there is only one seamless plate underneath the English Channel. The nearest plate boundaries are several hundred kilometers away. So the Channel Tunnel, dubbed the Channel, 1 50-kilometer train channel beneath the English Channel, is quite safe.

Where do we get the phrase "Sleep Tight" from?

It comes from Shakespearean England via thousands of children's bedtimes. William Shakespeare first gave "Tightly" the meaning "effectively" or "well" in his 1598 play The Merry Wives of Windsor, where Falstaff asks a servant to deliver "these letters tightly".

By the 18th century, the word was also used as an adjective and it was in this form that it became part of the rhyming couplet "Good night. Sleep tight" probably dreamed up by an anonymous mother to wish her young child a pleasant sleep. The subsequent popularity of this rhyme means that the phrase lives on today, despite its exact meaning being largely forgotten.