mercury or quicksilver........Barometer?

just discovered a jar of Mercury in my fathers attic......shock horror.Aparantly it was liberated fom his work many years ago as he had a notion to make a Barometer.question is what do I do with it now as I am not intending to use it as he intended,could I sell it legally,what's it worth ?

Thanks for your assistance

Take care of your health! Deliver to the recycling center to take care of the dangerous mercury.

PS, Do not sell, you are responsible for others' health and the environment!

Keep it!

Loads of street cred like a AK47

Great fun to play with and you can test if things are real gold

Mercury salts are poisenous as is the vapour but the pure metal isn't. In the past it has been used as medicine taken orally. However owing to the vapour bit I wouldn't keep it in the house in case of fire nor risk spilling it in the house..

At school in physics lessons we made barometers and poked fingers into it to feel the huge buoyancy effect but they got paranoid about a little copper suphate for plating experiments.. However over in the chemistry lessons we used hundreds of poisons but on converting the lethal mercuric oxide into pure mercury they got all silly and panicked to flush it down the drain.

That reminds me, I have tucked away somewhere in my workshop a 4" long, beautifully made plumb-bob. It belonged to my grandfather.

I don't know if he made it himself or purchased it, I have never discovered a manufacturers name on it.

Anyway, one day I decided to take it apart and it was a good job I was holding it upright because when I unscrewed the inner metal plug I could see it was full of mercury.

I ask the question, why on earth would anybody make a plumb-bob with mercury in it?

I suppose it could have been used as a damping medium to minimise the swing.

I would be interested to see other peoples comments on this rare device.

Len. P.

Hang on to it by all means - it can be very handy stuff to have on hand when the need arises, and not so easy to get hold of any more.

Hi Len,

The thing you have found may be the weight for the end of a pendulum. I think I have heard of this method to provide temperature compensation. As the mercury expands its centre of gravity will rise with respect to the bottom of its container. This can compensate for the increase in length of the main part of the pendulum.

Les.

There's logic to your theory Les that I had not considered.

I will endeavour to find it and place a picture on the forum tomorrow with a fuller description.

Len.P.

Try dipping the edge of a small piece of aluminium sheet about 16swg in the mercury. The mercury amalgamates with the alloy and hold it in suspension where it is attacked by the oxygen in the air. The alloy edge will begin to grow a layer of oxide which curls away and if you leave it, the entire piece of alloy will eventually eat away.

You might contact someone who repairs old barometers (Google "barometer repairs" ) and see if they will make you an offer.

Andy

Edited By Andyf on 11/04/2012 09:25:14

Don't take it to a waste disposal centre. It is quite valuable. Mercury can be readily obtained from clockmaking suppliers and currently costs about £200/kilogram.

As has been said, it is not particularly dangerous in its liquid state. Just don't heat it and keep it in an airtight container. Be careful not to leave spilled mercury lying around as it can gradually release vapours.

Russell

You could take up making top hats

That's why mercury or mercury-containing items are not permitted on aircraft - it's not worth the risk of mercury escaping as a certain consequence will be its attacking the airframe!

As regards barometer manufacturers - there was an EU edict last year that outlawed mercurial barometers. There was a Downing Street on-line petition that collected a lot of signatures which were then (predictably) ignored!

I was recently told by someone in Academia that the current anti-mercury H&S attitude is what is causing so many ex-college & ex-Uni Fortins & Kew Pattern barometers to appear on eBay.

Best regards,

Swarf, Mostly.

I just wish when considering Health & Safety issues that people would stop confusing Hazard with Risk!

Two hazards of mercury not generally known: first, the vapour pressure (in effect, the amount released into the atmosphere) increases markedly as you get to tiny drop sizes. This means that spilled mercury, as it tends to divide into tiny specks, is more dangerous than mercuy in bulk, and it is virtually impossible to pick up all the specks. Second, it is steam volatile; this means that if you boil water which has mercury in it, the steam will also contain mercury vapour and be potentially lethal.

Neither should prevent a careful worker using it, but one needs to be aware of them. ISTR that sulphur powder is recommended as a way of neutralising spilled mercury (forms mercuric sulphide, one of the most insolble salts known and thus fairly low hazard) - but don't take my word for it, research it yourself if you use mercury.

David

As promised attached are some pictures of my grandfather's Plumb-bob/pendulum whatever.

The small male tapered section you can see has a fine groove cut into the taper.

When the fine wire or fine twine used to suspend the device was fitted through a very small hole in the top of the mating tapered cup it would have been located along this groove and the end passed through the cross hole visible in the picture. The mating tapered cup would then have been pushed down onto the male section thus trapping the wire/cord/twine, a bit risky I would have thought. The tapered cup disappeared years ago.

The largest dia. of the taper is only 1/4", the length of the taper is 3/8". The overall length is 5 1/2" and diameter is 3/4".

Note also the spool arrangement which would have been used for storing the suspending medium which I think had it been fine wire, could have caused some coiling problems!

You can just make out the slotted screwed plug in the main body behind which is the quantity of Mercury.

Len. P.

P.S. I know it needs cleaning up.

Edited By The Merry Miller on 11/04/2012 12:14:11

Edited By David Clark 1 on 11/04/2012 12:51:23

Theres a mercury barometer hanging on the wall about 10ft away from me now, on the same board is a thermometer -- non mercuric, alcohol I think, red, not silver. Ian S C

Hi Len,

I think you are right that it is a plumb bob. If you Google "mercury compensated pendulum" all the pictures show the pendulum consisting of two glass tubes containing the mercury. This is like the one I saw when i was in my teens (50 + years ago.).

Les.

Definitely dont take it to a recycling center, its worth a lot of money,it is also heavy, which may explain it being in your plumbob.