David Wilkinson > wrote:

>But the removal and replacement of the bowl (a large sudden change,
>which should overcome any inherent "stickiness") clearly demonstrates
>that the bowl has "lost weight". i.e. the scales have changed their
>concept of the "zero point".
>
>It would be interested to see if the experiment could be repeated a
>number of times until the weight of the bowl registered "zero".
>
>Based on the evidence to date, I could well believe that the scales are
>adjusting their "zero point" over time.

Yes indeed. But if anybody's still doubting, look at this:

1. Weigh a spoon, a cup, and a bowl in turn - 30g, 194g, and 274g.

2. Slowly add 20g of powder to bowl and take combined weight - 278g.
16g lost this time.

3. Without zeroing, weigh spoon, cup, and bowl again - 14g, 176g, 258g.
Each is 16g or 18g lower (the scale increments in 2g steps).

So the zero point has shifted by about -17g.

--
Farry