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Yep, really nasty stuff if you inhale it in large quantities.

Lizzy

Galinstan. AFAIK it has a pretty low vapour pressure, since its boiling point is obscenely high.

Its also 'kin expensive !!

Steve

Well, a brief google search revealed commercially-available mercury-free barometers of normal size that are reputed to be accurate, so have a look and see what they're using.

On or around Fri, 27 Mar 2009 08:18:33 +0000, Ian Rawlings enlightened us thusly:

because otherwise the instrument is the wrong size. Atmospheric pressure supports a column of approximately 30" of mercury, against a more-or-less vacuum on the other side. This is another reason for the fluid not evaporating readily at normal temperatures.

You could make a barometer with another fluid, and a different length column. But I specified "replacement fluid for an existing instrument".

On or around Fri, 27 Mar 2009 09:27:56 +0000 (GMT), "Dave Liquorice" enlightened us thusly:

not to mention fluorescent lamps, with mercury vapour. Someone mentioned seeing free mercury in a skip wherein a lot of tubes had been smashed.

Ah right, that one passed me by completely as I suspect you'd figured! Yes you'd need a direct plug-in replacement for mercury to replace mercury.

Mind you I've read about it being banned for the manufacture of barometers while old barometers remain legal, but not anything about whether mercury will be allowed to be put into old thermometers that need repair so that might not be an issue, depends on whether it's covered or not.

Thermometers? Barometers I mean!

On or around Fri, 27 Mar 2009 15:28:09 +0000, Ian Rawlings enlightened us thusly:

Applies to thermometers as well, mind, if they're mercury type.