On 15 Feb, 12:36, Peter Campbell Smith wrote:
"Mike Cawood, HND BIT" wrote :

There will also be some people who for bizarre reasons not worth
going into think that the symbol pronounced "pound" is a
noughts-and-crosses grid.

That's because the hash symbol in US keyboards is in the same place as
our pound symbol (shift 3).
Mike.

I believe the reason # is called a pound sign by Americans is that it is
sometimes used in the USA to mean pounds weight. In American usage, #3
means 'number 3' and 3# means '3 lbs'. The latter is a bit old-fashioned,
but you see it sometimes in markets and the like.

Peter



Which tallies with James Robinson's explanation upthread - in case
anyone missed it I shall quote it below:

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On 15 Feb, 02:03, James Robinson wrote:

(snip)

It is also because the # glyph, when used after a number in script in the
US means the same as lb. It appears to have evolved as a result of clerks
quickly scratching lb. with a line through it on packages:

http://en.wikipedia.org/wiki/Number_sign
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