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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

The update was successful in that we were able to install some new hardware! (Which might result in a slightly snappier site.) I will need to do a bit more work this afternoon to get the forum software updated, which might have more impact in terms of the spam.

The parent is not the customer. The Student is the customer. The whole purpose of education is to better a person's life, and that person is the student.

Also, with folks directly paying for education (as we can see in university system of a number of countries) there is a stronger incentive for things like grade inflation and student retention.

This is more usually stated as the 'grandfather paradox', Moon, and yes it does violate causality. As usually stated, you go back in time and kill your grandfather. But then, you were never born to be able to go back in time. So your grandfather still lives, you are born , and travel back to kill him. But then you couldn't have ... This is the loop Sabine was talking about. And it doesn't necessarily involve actual travel in time either. Say you send a manuscript of Shakespeare's \\\romeo and Juliet back to William, who then publishes it, so that you, in the future, can send a copy back to him. Who actually wrote Romeo and Juliet ? What exactly 'caused' the play ?

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.

"Ooh, look at my little Johnny, he's the only one marching in step."