Charles Ellson wrote:
On Tue, 24 Jun 2008 19:34:08 -0500, Stephen Sprunk
wrote:
The issue at hand, though, is that neither of those things help the
blind figure out what they're holding; you need different sizes,
braille, or something similar that can be distinguished solely by touch,
and as of today US notes have nothing helpful in that area -- they all
feel exactly the same.

I recall some notes I had a while back when traveling (FRF? NLG? AUD?
NZD?) had clear sections that one could feel and, if given a few
seconds, determine the shape and thus what denomination the note was.
That's an interesting possibility as an alternative to different sizes
or braille. However, I don't know if that would be compatible with the
US's use of cloth notes...

BoE notes have holograms integrated into the (made from rag IIRC)
paper so mixing materials doesn't seem to be a problem.

Interesting. I assume the holograms are attached on top of the rag,
though, instead of integrated into a hole in the material?

With Braille I suspect the difficulty lies with the inconstant thickness
resulting or the eventual flattening of the "dots".

That's one problem; another is that the notes get rather abused in
circulation, being crumpled up, put through washing machines, etc. and
braille relies on having a flat medium, not a wrinkly/soft one.

Punching holes in the notes is probably not an option

Actually, that was my first thought, but obviously the largest notes
would have to have the fewest and/or smallest holes, and you'd have to
study how to do it in a way that wouldn't increase tearing (a problem
for our cloth notes already).

so relying on textural differences seems to be the remaining option
if the size and/or colour can't be changed.

Color can easily be changed for notes above USD1, but that doesn't help
the blind. There are millions of vending machines that take USD1 bills,
though, so any changes to those are impractical. The transition to
coins was supposed to solve that, but hasn't happened yet.

Possibly a variation on the BoE holograms could provide textural
"dots" but how many different denominations of dollar note would need
to be identified ?

We currently have USD 1, 2, 5, 10, 20, 50, and 100 notes in circulation.
There also used to be USD 1000 notes in circulation, but they were
withdrawn a few decades ago; I expect USD 200 and 500 notes to
eventually be circulated, as well as a return of the USD 1000 note, in
time due to inflation, but not for several decades.

S