michaelmcbain (2) [Avatar] Offline
The site www.nationalatlas.gov, from which the data for some of your examples is drawn [suach as chapter 1] is being decommissioned on 14 September 2014. USGS say they are moving it across to nationalmap.gov, so you might want to partially future-proof the 2nd edition.
regina.leo (265) [Avatar] Offline
Re: nationalatlas.gov being decommissioned

Thanks for the update. We'll make a note of it in book.