nerd

This is also how they cut rocks in ancient egypt I believe? Not with water, mind you, but would use a pretty mediocre if not useless saw but would drop sand in there, so it was actually the sand cutting the rock

I think water by itself can randomly break a few loosely bound atoms off the surface of anything. But the rate of that dissolution is dwarfed by the wear effects of the sediment being transported by the water, which is the primary material remover.

So.. why don't those abrasive materials destroy the hair in the drain?? Explain yourself