I've got a piece of string

[bibblebub]

How long is it?

[NazNomad]

27½ inches.

[sherrardk]

2 x the length from the middle to the end

[snags]

Which is 69.85 cms which sounds longer...

[NazNomad]

Not if there's a knot in one side

[DTCwordfan]

as long as you want it to be, from end to end.

that's my gut guess.....

[bibblebub]

But which end do you start with when measuring it?

[DTCwordfan]

the beginning one

[mollykins]

Depends which hand you hold the ruler in and which the string.

[bibblebub]

spoilsport

[DTCwordfan]

send bibble a few clues to solve - brilliance there.....probably worked on Enigma

[bibblebub]

I was best boy on Enigma

[douglas9401]

Infinite, in theory.

[berniecuddles]

get knotted!

[bibblebub]

tying a knot in it is necessary sometimes

[mollykins]

But if using a ruler you'd measure from left to right because thats the way the numbers go on it.

[bibblebub]

Unless one uses a left-handed ruler. Incidentally Bill Clinton was a left-handed ruler, don't know what he used his right hand for.

[TTG]

"it" is 2 letters long.

:-)

[bibblebub]

you win TTG, your turn