What is this strange piece of scientific glassware?

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mr_breen
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What is this strange piece of scientific glassware?

Post by mr_breen »

I am doing a home cleanout for a relative who owns a decent amount of lab and scientific equipment. I came across this very strange piece of glassware. There is nothing on the unit telling me what it is and I have literally no idea what it is used for. Unfortunately, the owner (my uncle) is not able to help either.

I'd love to know what it is used for. The more I look at it, the more impressed I get with the complexity of the glass work. It must have been very difficult to create. I almost wonder if it is a one of a kind item created for just one specific purpose. Even the wooden base is nicely done.

Here are some pics:

http://i.imgur.com/OMFTaNW.jpg
http://i.imgur.com/fq5EKqr.jpg
http://i.imgur.com/VYyGUMM.jpg
http://i.imgur.com/pEiz1hb.jpg

If anyone has any idea what this is, please let me know. If it has some general purpose use, I'm probably going to try and donate it to someone who can use it. Thanks
moghopper
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Re: What is this strange piece of scientific glassware?

Post by moghopper »

There is an OLD webpage for "Research and Development" glass products at http://www.angelfire.com/ca5/RandDGlass ... ss.htm.htm

It looks like they did a lot of custom work.
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Re: What is this strange piece of scientific glassware?

Post by triceratop »

In addition to modhopper's comment, large research universities often have dedicated glassblowers who design scientific glassware for unique reactions and experiments. The LA Times recently did a story on this.

I would guess that this is some kind of pressure gauge.
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Re: What is this strange piece of scientific glassware?

Post by Loik098 »

Since this instrument is measuring microns (micrometer of mercury) in what appears to be a closed system, I believe this is some sort of vacuum gauge. Vacuum gauges are used to measure absolute pressure in petrochemical, pharmaceutical, automotive and other industries. This also looks to me to be a display model or teaching model.

You could always call the company (there's a different phone number on their website than the one shown in your pictures) and ask them.
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Re: What is this strange piece of scientific glassware?

Post by dbr »

Loik098 wrote:Since this instrument is measuring microns (micrometer of mercury) in what appears to be a closed system, I believe this is some sort of vacuum gauge. Vacuum gauges are used to measure absolute pressure in petrochemical, pharmaceutical, automotive and other industries. This also looks to me to be a display model or teaching model.

You could always call the company (there's a different phone number on their website than the one shown in your pictures) and ask them.
The increasingly precise markings in microns and the ending at an absolute zero would support the suggestion of some sort of vacuum guage. I agree this looks like a teaching model or something pretty old.
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Re: What is this strange piece of scientific glassware?

Post by neilpilot »

It's called a McLeod gauge, used to measure very low pressures (i.e. vacuum down to 10-6 torr)
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Re: What is this strange piece of scientific glassware?

Post by mr_breen »

neilpilot wrote:It's called a McLeod gauge, used to measure very low pressures (i.e. vacuum down to 10-6 torr)
Thank you so much for giving me the name of this device. I had no way to find that out on my own. I just did some reading. It seems like they still have a very limited purpose in certain applications today. Now, I'm going to have to try and find someone that would like one. Thanks again.
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Re: What is this strange piece of scientific glassware?

Post by RudyS »

These sell on eBay. Packing for safe shipping would be a challenge, but worth looking into.
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Re: What is this strange piece of scientific glassware?

Post by Winthorpe »

neilpilot wrote:It's called a McLeod gauge, used to measure very low pressures (i.e. vacuum down to 10-6 torr)
Yes. I used one of these every day during my research days (PhD in synthetic organic chemistry). This one looks like it's probably from the 1950s or 60s. We would use it while evaporating volatile solvents from non-volatile things, distillation of liquids under high vacuum, flash distillations.

If you google vacuum line or Schlenk line, you can see the sorts of setups in which a McLeod gauge would be used. With a bit of mercury, yours appears to be in perfectly good working order. I think pretty much any college or university chemistry department could make good use of it.
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Re: What is this strange piece of scientific glassware?

Post by Winthorpe »

triceratop wrote:In addition to modhopper's comment, large research universities often have dedicated glassblowers who design scientific glassware for unique reactions and experiments. The LA Times recently did a story on this.

I would guess that this is some kind of pressure gauge.
Yes. All large universities have a dedicated full-time glassblower in the chemistry building. A talented glassblower can do amazing things. When I was a graduate student, he was like my best friend whenever he was able to repair a $500+ piece of glassware that I cracked. Rule #1 was always be friendly to the glassblower. If he didn't like you it was not repairable or it was going to take 3 weeks for him to get to it.
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Re: What is this strange piece of scientific glassware?

Post by Epsilon Delta »

Winthorpe wrote: If you google vacuum line or Schlenk line, you can see the sorts of setups in which a McLeod gauge would be used. With a bit of mercury, yours appears to be in perfectly good working order. I think pretty much any college or university chemistry department could make good use of it.
Are people still using mercury, even in research labs? I would have thought the lab safety officer would require you to prove that there was no alternative. If you tried that for a pressure gauge he would chase you with a pointed object.

People used to be a lot more blase about mercury, some of my chemistry teachers where literally "mad as a hatter". Quite a few old chemistry and physics labs are still off limit because there are pounds of split mercury oozing out of the nooks and crannies.
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Re: What is this strange piece of scientific glassware?

Post by Shackleton »

It is really beautiful. If I had any sort of association with that type of equipment in my past, I'd want it for my office as a piece of art and a pleasant reminder of those times.
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Re: What is this strange piece of scientific glassware?

Post by livesoft »

Epsilon Delta wrote:People used to be a lot more blase about mercury, some of my chemistry teachers where literally "mad as a hatter". Quite a few old chemistry and physics labs are still off limit because there are pounds of split [sic] mercury oozing out of the nooks and crannies.
That last sentence is total hyperbole such that I would not be surprised if snopes.com had something about it. "pounds"? "oozing"? With such visible and massive evidence of pounds of oozing Hg I would think the safety folks would find it easy to gather up and wait for the next oozing. :shock:
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Re: What is this strange piece of scientific glassware?

Post by mouses »

livesoft wrote:
Epsilon Delta wrote:People used to be a lot more blase about mercury, some of my chemistry teachers where literally "mad as a hatter". Quite a few old chemistry and physics labs are still off limit because there are pounds of split [sic] mercury oozing out of the nooks and crannies.
That last sentence is total hyperbole such that I would not be surprised if snopes.com had something about it. "pounds"? "oozing"? With such visible and massive evidence of pounds of oozing Hg I would think the safety folks would find it easy to gather up and wait for the next oozing. :shock:
I think it's Ep Del who was in contact with mercury :D
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Re: What is this strange piece of scientific glassware?

Post by dbr »

People have been blase about all kinds of things and mercury would be far from the worst. There are certainly things in any research lab today that are more harmful than mercury and there always have been. Awareness and regulation regarding handling is much improved, we hope.

The real reason a gauge like that is obsolete and useless in modern practice is lack of interface to digital electronics plus smaller size and durability of modern sensors not to mention sensitivity and accuracy far beyond a mercury gauge.
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Re: What is this strange piece of scientific glassware?

Post by Epsilon Delta »

livesoft wrote:
Epsilon Delta wrote:People used to be a lot more blase about mercury, some of my chemistry teachers where literally "mad as a hatter". Quite a few old chemistry and physics labs are still off limit because there are pounds of split [sic] mercury oozing out of the nooks and crannies.
That last sentence is total hyperbole such that I would not be surprised if snopes.com had something about it. "pounds"? "oozing"? With such visible and massive evidence of pounds of oozing Hg I would think the safety folks would find it easy to gather up and wait for the next oozing. :shock:
I'm specifically thinking about the clean up of the old Cavendish lab. When it was decommissioned the hazmat teams removed pools of Mercury from under the floor. When they went back to check they had got it all there was more, this cycle repeated for quite a few years, hence oozing.

It's hard to overstate how casually people used to handle mercury. Kids would pour in onto a table and chase it around for amusement. If there was a large enough pool people would bathe in it (well, float on it, submerging would be hard).
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Re: What is this strange piece of scientific glassware?

Post by Epsilon Delta »

dbr wrote:People have been blase about all kinds of things and mercury would be far from the worst. There are certainly things in any research lab today that are more harmful than mercury and there always have been. Awareness and regulation regarding handling is much improved, we hope.

The real reason a gauge like that is obsolete and useless in modern practice is lack of interface to digital electronics plus smaller size and durability of modern sensors not to mention sensitivity and accuracy far beyond a mercury gauge.
Yes, there are things more dangerous than mercury. But you have to get permission to use them. Before you get permission you have to justify that there is no suitable alternative. It would be easy to interface a mercury pressure gauge into modern electronics, but since, as you said, non-mercury gauges are better in pretty much every respect a request to do so would not be approved, IME it would be meet with jocular threats of physical violence or involuntary commitment.
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Re: What is this strange piece of scientific glassware?

Post by neilpilot »

Epsilon Delta wrote: Are people still using mercury, even in research labs?
Have you had to replace your home thermostat(s) with non-mercury containing alternatives?
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Re: What is this strange piece of scientific glassware?

Post by Epsilon Delta »

neilpilot wrote:
Epsilon Delta wrote: Are people still using mercury, even in research labs?
Have you had to replace your home thermostat(s) with non-mercury containing alternatives?
I've never owned a mercury containing thermostat. I do know people who replaced them before selling a house. It's less than $20 so why not? just hope the purchaser doesn't notice the lead paint and asbestos.

But unlike a thermostat lab equipment does not just sit there working for decades on end. It gets set up and taken down. Recently if you set up a mercury pressure gauge you'll have to go to the person with the keys to the hazmat cabinet and ask for some mercury, at which point I imagine the answer is "No", "H*** no", or chasing you round the lab with a pointed stick. Certainly that's my experience. So I'm asking any practicing chemist etc. when was the last time you used a mercury pressure gauge, or even saw somebody else using one.
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Re: What is this strange piece of scientific glassware?

Post by dbr »

Epsilon Delta wrote:
neilpilot wrote:
Epsilon Delta wrote: Are people still using mercury, even in research labs?
Have you had to replace your home thermostat(s) with non-mercury containing alternatives?
I've never owned a mercury containing thermostat. I do know people who replaced them before selling a house. It's less than $20 so why not? just hope the purchaser doesn't notice the lead paint and asbestos.

But unlike a thermostat lab equipment does not just sit there working for decades on end. It gets set up and taken down. Recently if you set up a mercury pressure gauge you'll have to go to the person with the keys to the hazmat cabinet and ask for some mercury, at which point I imagine the answer is "No", "H*** no", or chasing you round the lab with a pointed stick. Certainly that's my experience. So I'm asking any practicing chemist etc. when was the last time you used a mercury pressure gauge, or even saw somebody else using one.
I last used mercury in a device about twenty years ago. It was not a pressure gauge but did involve obtaining mercury, transferring it in and out of a device and operating the device. The use required a hazmat review which imposed certain use conditions and certain clean-up and sampling procedures during use and when the use was over. I also did devise an alternative experimental configuration that did not use mercury, but there were some good reasons at the time. If I had to do the same experiments today use of the mercury containing device would still be a reasonable consideration in my opinion.
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Re: What is this strange piece of scientific glassware?

Post by Mudpuppy »

Shackleton wrote:It is really beautiful. If I had any sort of association with that type of equipment in my past, I'd want it for my office as a piece of art and a pleasant reminder of those times.
As others have said, a university most likely has newer measuring equipment. But, as you point out, it could still have value as an artistic piece for individual chemists or display piece for a chemistry museum. So the value is more in the historical/artistic realm than the practical, everyday chemistry realm.

And I hope the OP is taking care while clearing out his uncle's home chemistry lab. I recall there was a thread on the dangerous chemicals the uncle still had stored at home, but the OP never updated on how the chemicals were disposed of. And the glassware could have residuals of such chemicals remaining.

My suggestion to the OP: It might be worth cultivating a friendship with a local chemist, say someone at the local university or college who has an interest in historical chemistry, to help clear out your uncle's garage. They would know if something harmful is found, and how best to sell the niche equipment.
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Re: What is this strange piece of scientific glassware?

Post by FreeAtLast »

Epsilon Delta wrote:
livesoft wrote:
Epsilon Delta wrote:People used to be a lot more blase about mercury, some of my chemistry teachers where literally "mad as a hatter". Quite a few old chemistry and physics labs are still off limit because there are pounds of split [sic] mercury oozing out of the nooks and crannies.
That last sentence is total hyperbole such that I would not be surprised if snopes.com had something about it. "pounds"? "oozing"? With such visible and massive evidence of pounds of oozing Hg I would think the safety folks would find it easy to gather up and wait for the next oozing. :shock:
I'm specifically thinking about the clean up of the old Cavendish lab. When it was decommissioned the hazmat teams removed pools of Mercury from under the floor. When they went back to check they had got it all there was more, this cycle repeated for quite a few years, hence oozing.

It's hard to overstate how casually people used to handle mercury. Kids would pour in onto a table and chase it around for amusement. If there was a large enough pool people would bathe in it (well, float on it, submerging would be hard).
During my career, more than once I had to clean up small, elemental mercury spills. It was a major pain in the a** because those minuscule spheres of Hg can hide anywhere. Don't forget to clean out the drain traps!

The Cavendish lab was also infamous for its contamination with radium and its derivative radioactive species. In the time of Rutherford, he and his colleagues would collect CURIE-sized allotments of Ra for various experiments. Try to do that today and you wouldn't be chased with a pointed stick; you would simply be summarily shot and your remains rocketed into the Sun.

Correction: The Cavendish investigators would collect allotments of gaseous radon emanating from the solid radium bromide. The problem of subsequent radioactive contamination remains the same.
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Re: What is this strange piece of scientific glassware?

Post by bayview »

Epsilon Delta wrote:...It's hard to overstate how casually people used to handle mercury. Kids would pour in onto a table and chase it around for amusement...
Were you in tenth-grade chemistry with me, 1969? :D
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Re: What is this strange piece of scientific glassware?

Post by livesoft »

Winthorpe wrote:
neilpilot wrote:It's called a McLeod gauge, used to measure very low pressures (i.e. vacuum down to 10-6 torr)
Yes. I used one of these every day during my research days (PhD in synthetic organic chemistry). This one looks like it's probably from the 1950s or 60s.
I've been e-mailed from an internet sleuth who looked at the images of the gauge which helps pin the date at least in the 60s as you noted:
Zip codes came into existence in 1963, so the McLeod gauge is not from the 50s. The company label includes both area code and zip, but area codes are older.

"Area code 415 is a California telephone area code that was one of the first three original area codes established in California in October 1947." (It wasn't used by the public until 1951)
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Re: What is this strange piece of scientific glassware?

Post by retiredjg »

Except for one thing - the date on the apparatus itself is 3/88….

http://i.imgur.com/VYyGUMM.jpg
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Re: What is this strange piece of scientific glassware?

Post by mr_breen »

livesoft wrote:
Winthorpe wrote:
neilpilot wrote:It's called a McLeod gauge, used to measure very low pressures (i.e. vacuum down to 10-6 torr)
Yes. I used one of these every day during my research days (PhD in synthetic organic chemistry). This one looks like it's probably from the 1950s or 60s.
I've been e-mailed from an internet sleuth who looked at the images of the gauge which helps pin the date at least in the 60s as you noted:
Zip codes came into existence in 1963, so the McLeod gauge is not from the 50s. The company label includes both area code and zip, but area codes are older.

"Area code 415 is a California telephone area code that was one of the first three original area codes established in California in October 1947." (It wasn't used by the public until 1951)
That's interesting. But, look at label at the first photo in the set. It lists a date of 3-88. I just assumed that meant it was made in 1988. But, then again, maybe that label was applied long after it was actually made - maybe during a re-calibration of the gauge?

I really can't be sure. My uncle's career spanned the late 60's into the early 2000's. He probably was acquiring stuff all through that period. Also, the rubber hose attached to it is cracked, but still pliable. Not sure if rubber from the 60's would still be pliable by now.
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Re: What is this strange piece of scientific glassware?

Post by arthurdawg »

Neat piece of equipment though... reminds of Quantitative Analysis and Physical Chemistry lab!
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Re: What is this strange piece of scientific glassware?

Post by tooluser »

To me it looks like a sales display of something the company is capable of producing. Hence it is mounted to a display stand, and has the company name, address, and telephone number on it - there was no publicly available internet in 1988. Something a salesman would carry to sell capability.
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Re: What is this strange piece of scientific glassware?

Post by mr_breen »

tooluser wrote:To me it looks like a sales display of something the company is capable of producing. Hence it is mounted to a display stand, and has the company name, address, and telephone number on it - there was no publicly available internet in 1988. Something a salesman would carry to sell capability.
At first, I thought it light be a display model, too. But the wooden stand has a purpose. The entire portion containing the glass actually rotates 90 degrees. As I understand it, rotating is done when taking measurements. So, everything there seems to have a purpose, even the small wood peg on the right side (it keeps the glass from rotating too far to the right.)
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Re: What is this strange piece of scientific glassware?

Post by Shackleton »

retiredjg wrote:Except for one thing - the date on the apparatus itself is 3/88….

http://i.imgur.com/VYyGUMM.jpg
The date appears to have been hand written with a black marker. Right above it it says "Cert By JM" where again the "JM" part looks hand written. I'd assume that 1988 was the last time it was calibrated or certified accurate.
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Re: What is this strange piece of scientific glassware?

Post by retiredjg »

We'll probably never know. I interpreted it to mean it was piece number 472, built in 3/88, certified by JM. But it could just as easily be last calibrated 3/88.
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Re: What is this strange piece of scientific glassware?

Post by pshonore »

bayview wrote:
Epsilon Delta wrote:...It's hard to overstate how casually people used to handle mercury. Kids would pour in onto a table and chase it around for amusement...
Were you in tenth-grade chemistry with me, 1969? :D
I recall having some fun with Sodium and Potassium which I think were kept under water? Its been over 50 years.
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Re: What is this strange piece of scientific glassware?

Post by jpelder »

pshonore wrote:
bayview wrote:
Epsilon Delta wrote:...It's hard to overstate how casually people used to handle mercury. Kids would pour in onto a table and chase it around for amusement...
Were you in tenth-grade chemistry with me, 1969? :D
I recall having some fun with Sodium and Potassium which I think were kept under water? Its been over 50 years.
Definitely not under water! Probably mineral oil. NA or K plus H2O makes H2, O2, and lots of heat! Then a nice BOOM! Chemistry is fun
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Re: What is this strange piece of scientific glassware?

Post by livesoft »

retiredjg wrote:We'll probably never know. I interpreted it to mean it was piece number 472, built in 3/88, certified by JM. But it could just as easily be last calibrated 3/88.
I'm waiting for someone to say they called the phone number. :)
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Re: What is this strange piece of scientific glassware?

Post by retiredjg »

livesoft wrote:
retiredjg wrote:We'll probably never know. I interpreted it to mean it was piece number 472, built in 3/88, certified by JM. But it could just as easily be last calibrated 3/88.
I'm waiting for someone to say they called the phone number. :)
I'm waiting for someone in Berkeley to go by. :happy

The internet seems to think the shop is now for auto glass although with the same name as before. Research and Development Auto Glass makes me laugh.

ETA…I think they are still in business as a custom glass producer. They are still listed in a 2015 wine website and there's a yelp review from 2015 (not a happy customer).
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Re: What is this strange piece of scientific glassware?

Post by livesoft »

Perhaps they make custom-made bongs nowadays, too.
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Re: What is this strange piece of scientific glassware?

Post by obgraham »

Ah yes, Mercury. Every chem lab had a little jug of the stuff on the reagent shelf.

I recall in high school we nerds would pilfer it bit by bit for our own basement chem labs. You could polish a silver quarter with some mercury and it would shine like new. And if you boiled some mercury over a butane flame a nifty orange vapor would be released!
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Re: What is this strange piece of scientific glassware?

Post by PoeticalDeportment »

dbr wrote:People have been blase about all kinds of things and mercury would be far from the worst. There are certainly things in any research lab today that are more harmful than mercury and there always have been. Awareness and regulation regarding handling is much improved, we hope.
In college (late 90's early 2000s), I worked in a research chemistry lab. We had some inexpensive shelving made from horizontal plywood boards with nails hammered vertically in the corners which were connected by string to keep bottles of chemicals from falling off the edge. I remember seeing a several kilogram bottle of potassium cyanide several feet above the cement ground on one of these shelves which I was always slightly uneasy about. I wouldn't tolerate a similar safety hazard in my workplace nowadays, but as a college student I didn't really overthink it. I did take a picture of it though which I still have - I guess it was more amusing than alarming to me at the time.
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Re: What is this strange piece of scientific glassware?

Post by jharkin »

Epsilon Delta wrote: I've never owned a mercury containing thermostat. I do know people who replaced them before selling a house. It's less than $20 so why not? just hope the purchaser doesn't notice the lead paint and asbestos.
You may never have personally purchased one, but unless you are under 20 years old or lived all your life in the tropics where buildings don't have heating systems you have almost certainly lived in a home with mercury switch thermostats at some point. You just probably never opened it up to look inside and see the mercury bulb connected to the bimetallic coil.

They only stopped making them about 10 years ago. I still see them in relatives houses and changed one out in a rental we used to live in as recently as 9 or 10 years ago.
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Re: What is this strange piece of scientific glassware?

Post by adamthesmythe »

I cannot think of any current application where a McLeod gauge would be a desirable solution. I used one as an undergraduate a long time ago and even then it was a clunky instrument.

It's a desk ornament now, nothing more.

By the way- mercury also used to be found in light switches, often a dozen or so in a house. Mercury switches had very smooth operation. In the lab, certain types of (hermetically sealed) relays have a small amount of mercury in them.
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Re: What is this strange piece of scientific glassware?

Post by dbr »

jharkin wrote:
Epsilon Delta wrote: I've never owned a mercury containing thermostat. I do know people who replaced them before selling a house. It's less than $20 so why not? just hope the purchaser doesn't notice the lead paint and asbestos.
You may never have personally purchased one, but unless you are under 20 years old or lived all your life in the tropics where buildings don't have heating systems you have almost certainly lived in a home with mercury switch thermostats at some point. You just probably never opened it up to look inside and see the mercury bulb connected to the bimetallic coil.

They only stopped making them about 10 years ago. I still see them in relatives houses and changed one out in a rental we used to live in as recently as 9 or 10 years ago.
Ours went away when we put in a programmable thermostat maybe 10-15 years ago. We actually had a plumber try to put one back in a few years ago.

I think we still have at at least one mercury filled medical thermometer in the house. Mercury thermometers were prime candidates for breakage trying to insert them in rubber stoppers back in chem lab.
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Re: What is this strange piece of scientific glassware?

Post by retiredjg »

dbr wrote:I think we still have at at least one mercury filled medical thermometer in the house.
I have a couple as well.
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Re: What is this strange piece of scientific glassware?

Post by arthurdawg »

PoeticalDeportment wrote:
dbr wrote:People have been blase about all kinds of things and mercury would be far from the worst. There are certainly things in any research lab today that are more harmful than mercury and there always have been. Awareness and regulation regarding handling is much improved, we hope.
In college (late 90's early 2000s), I worked in a research chemistry lab. We had some inexpensive shelving made from horizontal plywood boards with nails hammered vertically in the corners which were connected by string to keep bottles of chemicals from falling off the edge. I remember seeing a several kilogram bottle of potassium cyanide several feet above the cement ground on one of these shelves which I was always slightly uneasy about. I wouldn't tolerate a similar safety hazard in my workplace nowadays, but as a college student I didn't really overthink it. I did take a picture of it though which I still have - I guess it was more amusing than alarming to me at the time.

oh my.....!

That's rather scary.
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Re: What is this strange piece of scientific glassware?

Post by nisiprius »

I can confirm the casualness with which people used to treat mercury.

Various kids' parents would ask their dentist to give them a little. (It must have been a lot cheaper then, because dentists were willing to give away ounces of the stuff). Kids would bring it to school and show how to make (silver) quarters beautifully shiny by massaging a little mercury onto them.

You know the little handheld plastic maze games where you guided a tiny ball bearing through the maze? There were some that had a little drop of mercury in them.

My junior high school science teacher had a demonstration he liked to do--I'm afraid I don't remember what it was even supposed to demonstrate!. He would put some mercury in a test tube, sprinkle some copper sulfate crystals on top, and... get this... hold the test tube over a Bunsen burner. The crystals would begin to jump and dance around.

Any kid who went to the science shelf in the children's library would find books describing all kinds of cool electromagnetic things you could do with a little mercury. For example, make a springy coil of wire. Put a little mercury in a dish. Suspend coil with one end dipping into the mercury. Connect a battery (a #6 ignition cell, of course) with one end to the mercury and the other end to the coil. Current flows, creating magnetism. Magnetism causes the coil to pull itself together, pulling end out of the mercury, breaking circuit. Coil relaxes again, closing the circuit, etc.

You could do all sorts of neat things by floating magnets on mercury. Here's one illustration from "The Boy's Playbook of Science." That would have been an old book even in the 1950s but books like these were still on the shelves. There were a lot of "experiments" I'd have liked to do, but couldn't, because I couldn't get the sticks of sealing wax, the "lycopodium powder," or the "photographer's collodion," but mercury was no problem.

Image

I do have one regret. In those days I had never heard what mercury does to aluminum. Thank heavens for Youtube...

P.S. I am almost sure I read about people making reflecting telescopes using rotating dishes of mercury... the big advantage being that centrifugal force creates a perfect parabolic shape, and the big disadvantage being that they can only point straight up.

Wait, wait... WOW! Liquid mirror telescope
Currently, the mercury mirror of the Large Zenith Telescope in Canada is the largest liquid metal mirror in operation. It has a diameter of six meters, and rotates at a rate of about 8.5 revolutions per minute.
Yikes! Six meters! That gives you plenty of surface area for evaporation. Doubtless they have some way to deal with this (?)
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Re: What is this strange piece of scientific glassware?

Post by livesoft »

There are plenty of current household chemicals that are just as dangerous to one's health as the things described in this thread. Recipes to use them are available in books such as Abbie Hoffmann's Steal This Book or the CRC from the 1930's (recipe for nitroglycerin in your bathtub) or many others.

Everybody knows how to make Molotov's Cocktails and even how to make chlorine gas. Certainly many pesticides and herbicides and antifreezes will kill you. Even washing soda can be used to turn water into hydrogen gas and oxygen gas which are quite interesting gasses.
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Re: What is this strange piece of scientific glassware?

Post by arthurdawg »

Metallic mercury deserves handling with care... but organic mercury is much more deadly.


There was a tragic case involving a researcher who was a specialist in dimethylmercury who died after the exposure.


https://en.wikipedia.org/wiki/Karen_Wetterhahn
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Re: What is this strange piece of scientific glassware?

Post by FreeAtLast »

retiredjg wrote:
dbr wrote:I think we still have at at least one mercury filled medical thermometer in the house.
I have a couple as well.
I own a thirty year old sling psychrometer that uses thermometers filled with Hg. I use it to measure outside temperature and relative humidity after my daily run. Never shall I part with it.

When I worked, one of my responsibilities was to collect all the liquid Hg for proper disposal. So my office was full of old thermometers, thermostats, barometers (and other scientific instruments), and finally a large jar of it just sitting in a bucket next to my desk. I got some strange looks from visitors. It was quite expensive to get rid of it all legally.
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