This is an excerpt from the book "How to Invent Everything" which I thumbed through at a book store once. It's good, but not excellent. It skips over a lot of vital things (as can be expected) but one thing that really bugged me is the same thing that bugs me at the end of this article. The author loves to comment how things have been used for torture. While historically accurate, describing how the thing you just 'invented' can be used for torture... that just turns my stomach. I don't see the utility in bringing it up in this context.
You can watch this process, modulo medieval improvements (lime milk instead of urine for dehairing):