exchemist

Sometimes I wonder if this is the approach of the British Tory party to our National Health Service: starve it for years, demoralise the staff and then say, “Look, it doesn’t work.”

Knowing the difference between "refute", "rebut" and "disagree with", and between the singular and plural of criterion, would be a start. 😉 More seriously, surely the criteria for a new teacher are subject knowledge and evidence of the ability to teach, i.e. to motivate pupils to enjoy the subject and be able to show that they have learnt effectively, e.g. by good exam results. (Plus the usual hygiene factors of course.). But is this what you are interested in, or is it what should be in the syllabus? From your previous posts it feels as if the latter is more what concerns you.

Yes, we know what a microwave oven looks like. Your question has been fully answered, several times now. You are behaving like a neurotic timewaster. Kindly stop this nonsense.

Ah, so I now see. All power to your (collective) elbow, then.

I can't really follow all this but in any case Dave has fixed it. And the malicious-looking spam has gone, too, al hamdulillah!

Yup the ad tab is gone and so is the problem, apparently. Well done!

Now I can reply on the Mac, apparently. Have you done something? (The ad tab is no longer appearing.)

Nope still happening. Could be connected with a new advert tab that comes up from the bottom of the screen on the Mac, but not on the iPad. Seems the screen freezes if I scroll down far enough to touch it. Use from iPad seems OK however.

Some teething troubles. Screen scroll can freeze and cursor can disappear when responding using Quote button. This happens on Apple Mac running Safari on Monterey 12.6.4. However I seem able to use the site from my new iPad. Very odd.

No. The surface I am referring to is the enormous surface area of the micropores in the gel, not just the visible surface of the beads. This stuff is like a sponge, full of microscopic tubes and holes, and water is adsorbed on all the internal surfaces. It make no difference if a bead splits in half or something. You can read more about what silica gel is and how it works here: https://en.wikipedia.org/wiki/Silica_gel

Because it is adsorbed on the surface. It is stuck to it and only heat will dislodge it.

No. No.

I'm not a fan of this idea. My mother taught English at A-level for many years in the UK state system and one of her perennial challenges was parents that had limited ideas about what was good for their children. She fought for years with parents who didn't want their daughters to go to university, or who wanted them to study something that led to an obvious job, rather than the subjects they enjoyed. If the parents choose what subjects to fund for their children, you would risk removing the ladder that lets children climb to reach their academic potential. Even in the UK private sector the school sets out the curriculum and the parents go along with it.

There's an explanation of the process for separating rainwater from sewage here: https://www.wavin.com/en-en/News-Cases/News/Pros-and-Cons-of-separating-rainwater-from-sewers-to-prevent-sewer-overflow-in-urban-areas From the description it does not look as if any country has really embraced this idea fully, though there seem to be some pilots at municipality level, Vancouver perhaps being one. It is evidently a very costly and disruptive exercise to retrofit a twin-pipe system, though I suppose it could be put in place on new housing developments if planning regulations were changed to require it.

I was discussing the post to which I was responding, strange to relate.

They seem all to have observed something, but apparently nothing with a radar signature. Irritatingly this is presented to emphasise mystery rather than to dispel it, so no helpful details are provided. But if what the picture shows is correct in that the sun was just rising above the clouds, and what they saw was a bright light, my suspicions are aroused that this could have been some effect attributable to sunlight.

That does not happen.

I don’t believe you. Anyone advancing a theory scientifically would be able to present the observations that the theory tries to account for.

OK so let's see some of this "meticulously documented" research, then.

So no research then.

Where’s the research, then? Who did it, how and what was observed?

So far so good. Thanks for addressing so quickly. !

The problem with the real thing is there no real way to speed up the deposition of CaCO3 very much - though I seem to get quite a bit blocking the taps at home within a matter of years. I've never heard of making stalactites or stalagmites with sodium silicate and Epsom salts (MgSO4.7H2O) but I can see it might work. The picture actually shows stalactites rather than stalagmites. If you are really after stalagmites, then making a chemical garden might suit your needs. This too involves sodium silicate. Instructions here from the Royal Society of Chemistry: https://edu.rsc.org/experiments/making-a-crystal-garden/416.article . This, being designed for chemistry teaching, proposes various chemicals that you would need to order specially. But you could also try iron (II) sulphate, greenish but may go a bit rusty-brown, which is sold in garden centres for calcifuge plants, and copper sulphate, blue, which is or was sold, mixed with calcium hydroxide (I think), as something called Bordeaux mixture to control disease on plants, as well as a Epsom salts.

Dunno, but the OP seemed to want it.

No. It is as @Genadysays. Suggest re-reading my post and trying to get hold of the idea of how an image is formed. What I have been trying to explain is that all the light that hits your eye from the letter Q is focused , by the lens, on just one part of your retina ONLY, where it forms the shape of a letter Q (upside down, but don't worry about that for the present). Similarly for the light coming from the other letters. You could try reading this, which explains image formation by a lens at greater length: https://www.physicsclassroom.com/class/refrn/Lesson-5/Converging-Lenses-Ray-Diagrams