I learned so much about phosphorus and phosphorus-related things in this book. I think the coolest thing I learned was that phosphorus is not actually phosphorescent (it's luminescent!). My only complaint is that sometimes the author falls into what I feel is too much detail for a general audience. He starts talking about how the oxygen groups on phosphate attach to the whatever complex of thingy and how it blah blah blah...and my eyes go fuzzy for the rest of the page. However, those spells don't last long and pretty soon he's back into the interesting history and uses of phosphorus.