I spoke to one of the curators who told me a little about the project and explained that people were invited to make donations of quantities of water (they also have urine and spit samples!) that had some meaning to them.
"We currently have over 150 bottles in the collection, ranging from water from a holy river in India, to a burst London water main, ice from a Sussex field, a melted snowman, 20-year-old evaporated snow from Maine, condensation from a Falmouth window, Hackney rainwater, a new born baby’s bath water, Norwegian spit, three types of wee, two different breaths and water from a bedside table said to be infused with dreams."
Normally I'd have to spend some time thinking about an example of water that means something to me, as I'm afraid to say I'm pretty acclimatised to its ubiquity but amazingly I immediately thought of two examples that I'd like to submit to the collection. The challenge is acquiring them - in the case of the first it would involve giving money to quacks, in the second case it would involve considerations of health and safety.
My submissions (in the non-literal sense then, since I don't actually have them) to the Museum of Water are:
1. A bottle of alkaline water
Alkaline water is water whose pH is higher than regular water (which is fairly neutral). Tap water does apparently vary in its pH quite a bit (I seem to remember looking into it for reasons that are about to become apparent), but alkaline water comes in bottles and is definitely alkaline. Of course drinking alkaline water just means that once it gets into your stomach it probably doesn't put up much of a fight against the super-low pH of stomach acids, so as far as I can tell there isn't actually any point in drinking it.
But I've no objection to people selling or buying alkaline water, I'm sure it tastes lovely. What I do object to is people selling it and claiming that it can cure cancer and diabetes. And for that reason I asked Trading Standards to investigate a company doing exactly that and the next thing I heard the company had ceased trading. This surprised me as, given it's not illegal to buy or sell alkaline water, I'm sure they could have just continued selling it as bottled water with a slightly higher pH.
There are some other companies selling alkaline water but since they don't regularly breach the Cancer Act of 1939 they are free to do so without interference from me, though I might mock their claims occasionally.
My first submission would be a bottle of alkaline water then.
2. A bottle of 'heavy water' aka deuterated water
When I was doing a PhD that I never got anywhere with ('blunting the cutting edge of science' as my mum called it - learned loads, mostly that I'm a heck of a lot better at talking about science than doing it, though I'm pretty good at fixing technology) one of the things I did was submit some of my samples to NMR (nuclear magnetic resonance imaging).
I loved doing this, the NMR unit was housed in a double layer of liquid helium and liquid nitrogen (things that are normally gases at room temperature that were at such low temperature they were liquid) and there were lots of warnings around about not letting the liquids heat up which would 'quench' the magnet.
If that happened you were in danger of finding yourself in a room full of expanding unbreathable gas which also (a) displaces oxygen, making it extra hard to breathe and (b) exert extra pressure on the door making it hard to open. Also pretty terrifying I should think, happily I never experienced it.
Anyway, drama aside, the NMR unit I was using was 'reading' the signal from hydrogen atoms in the sample - these are your basic 1H atom which is everywhere. Because the sample is in solution there's a risk that you'll get signal from any of the 1H atoms that are in the solution and so... you use solvents that don't use that hydrogen atom but instead use the deuterated isotope (2H or D - so you get 2H
2O or D2O for water or CDCl3 instead of CHCl3 (chloroform)).
I don't think deuterated water is particularly dangerous to have lying around in a bottle, probably is a bit risky if you drink rather a lot of it. Another potential risk is that bottles were often previously sold with another ingredient in it that was used as an internal standard (a known amount of a chemical compound that gives you a standard against which you can compare your sample) and that chemical (trimethylsilane) isn't really something you'd want to drink - but I don't think it's included now.
But safely housed in a glass bottle with a screw lid - should be fine. So my second contribution is a properly stored bottle of heavy water.
Edit: @zeno001 has suggested I also include a bottle of homeopathic water, which would be infinitely diluted...
*for the BBC recording of a tribute to lyricist Don Black, which will be broadcast around Christmas.