Oh shit yeah that's right! Myne didn't even have super advanced physics knowledge but she's still upending her world XD and she had to figure it out herself from scratch, only based upon trial and error and the drive to keep pushing no matter how many times she fails! She REALLY digs deep into the nitty gritty about figuring things out, too - no convenient shortcuts!

I was always just a teeny tiny bit sad that she didn't happen to have known, at the time, the basics of how soap works. Her shampoo, I can't imagine it can do a particularly great job of cleaning without at least a trace amount of a alkaline solvent of some kind (usually we use lye) which is where "soapiness" comes from.

Soap is molecules that are electrostatically polar on one end (like water is) with a non polar chain (a lipid tail that is hydrophobic) on the other, so it sticks to grime AND water at the same time, allowing the water to pull the grime away (whereas the grime otherwise repels water)

One doesn't have to know the chemistry of saponification to understand that if you mix a strong alkaline with an oil, it makes soap. And... like ... she has a wood stove right there. Wood ash is where humanity historically used to get our lye.

But no, I LOVE Bookworm, it's STILL a lovely story and I will keep following it, of course!