It's been a while an update on the textbook, but there hadn't been much to say. We were waiting for reviewers, and started sending our editor e-mails asking what was happening just after the editor went on a month's leave, producing all sorts of fears of inadequacy. That the first review we got was from a friend probably isn't coincidence: the book covers a peculiar mix of mathematical subjects not many people study together, and we know a good fraction of them, and his book on some of the topics was one of our most heavily-used references.
The review was very positive, with particular praise for the exposition, which is gratifying since that was my most important contribution. (Some of my research is in it, sure, but I think my parts are the obvious pieces. Of course, I know those parts thoroughly.) He thinks our combination of subjects is unique and the book should be a valuable reference, again comforting. I wasn't sure the fact no books cover our particular combination wasn't because there's no need for our mixture. Granted that might be courtesy, but I don't think he'd have needed to be so specific if he was just being nice.
He also nastily pointed out actual flaws in the writing, particularly in repetitive segments. I tend to over-write and trim down, and while there's virtue in writing separate sections of a mathematics book so that you don't have to leapfrog through two-thirds of the pages to follow one proof, nobody needs the indicator function explained four times. The indicator function is defined for some set; it's equal to one if the argument is in that set, and zero otherwise. It doesn't sound like much, but it's a handy tool.
We're now going through what we dearly hope are final revisions and plunging towards completing the ready-to-print draft the start of June. Since we want to include more pictures, and we have good reason to discuss von Kármán trails -- a characteristic pattern of staggered rows of cyclonic storms; you can also create them by quickly dragging your finger or a pencil through water (they're named for Theodore von Kármán, a giant of aeronautics, a founder of the Aerojet rocket corporation, and of the Jet Propulsion Laboratory, and the person who proved that solid rockets could be made large enough to have military or scientific value) -- I may be able to work in a Project Gemini picture of the Earth into my mathematics book. And with the official LaTeX files the manuscript suddenly looks like a real mathematics book, gaining several hundred coolness points, and making typos and incomplete sentences painfully obvious.
Trivia: Within 40 years of the first compilation of Poor Richard's sayings as The Way To Wealth, it had been reprinted in 145 editions and in seven languages. Source: Benjamin Franklin: An American Life, Walter Isaacson.
Currently Reading: War for the Union, 1861-1862: The Improvised War, Allan Nevins.