tim... wrote:

"Roland Perry" wrote in message
...
In message , at 10:25:58 on Tue, 19 Jul 2016,
tim... remarked:

It's every much the same sort of thing: banning a commodity because
it's harmful/unethical or whatever.

There is a mile of difference between unethical and harmful, especially
when in normal use the item isn't harmful at all, it's only harmful if
it's abused.

Ivory hunting is harmful to elephants.

I was referring to the mercury instrument (I thought that was bleeding
obvious)

The problem with mercury is that even if not "abused" (whatever that
means) it has a tendency to get split, and when it does the tiny droplets
run everywhere and are very difficult to clean up.

thermometers are sealed units

(I have no idea about barometers, but assume likewise)

Barometers measure atmospheric pressure, so they have to be open to the
atmosphere to do this.

--
Jeremy Double