Andy wrote:
>
> Arri London > wrote:
>
> >
> >
> > NOYDB wrote:
> >>
> >> I find that I frequently want to adjust a recipe up or down in
> >> quantity. I use an old slide rule to set up the original proportion (
> >> set the 1 over the adjusted quantity; 2, 3, .5, whatever ) then read
> >> the new quantity directly under the original quantity. Sometimes
> >> there's a problem in measuring the new quantity exactly though.
> >>
> >> Anyway I was wondering if anybody else does this or if I'm just an
> old
> >> geek. I started using a sliderule studying electronics in the '70's.
> >
> > No I don't use my slide rule It was my primary school maths prize
> and
> > that was probably the last time it got used.
>
> What I found astonishing/interesting about the abacus was you could do
> math without having to write anything down in the process!!! You could
> just see it as patterns at a glance!!!
>
> Thanks to the Greeks for the invention!!!

Wasn't just the Greeks; other people as well.
>
> Andy

There is a tiny abacus in my possession. One of these years I may learn
to use it It is perfect for lightning calculations.