The term "John" as a slang for bathroom is thought to have originated from Sir John Harington, an English courtier. He is credited with inventing the modern flushing toilet in the late 16th century, hence the association. Over time, the term "John" became a colloquialism for the toilet or bathroom.
Based on facts, it was John Harrington who invented a device which was similar to the toilet in 1596. He was an important figure in the court of Queen Elizabeth I and he made the device for the Queen. Eventually the toilet came to be known as John. Apart from this, there is also a widespread belief that a man known as John Crapper invented the toilet. What happened is that people confused John Harrington of the Queen's court with that of Thomas Crapper.
'Bog' is a slang term sometimes used in Britain for a toilet.
"Toilet papier" is the term for toilet paper in Afrikaans.
No, "hopper" is not a slang term for a toilet. In some contexts, "hopper" can refer to a container used to hold materials in industrial settings, or to a device used in agriculture for spreading seeds or fertilizer.
An old (but still used elsewhere) term for public rest room, washroom, bathroom.
John Crapper invented the first toilet.
John A. Roebling did not have anything to do with the flush toilet. He was a civil engineer known for designing the Brooklyn Bridge. The flush toilet was invented by John Harington in the late 16th century.
"The head".
The term "water-closet" was an early term for a room with a toilet http://en.wikipedia.org/wiki/Flush_toilet
it was the first flush toilet
The toilet was invented by Sir John Harington in 1590.